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Copyright of Feed Industry is the property of Liaoning Provincial Institute of Agricultural Mechanization 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 Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental 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.)

To achieve rapid and accurate identification of valuable wood products, an analytical method was developed by combining electric soldering iron cauterization with soft ionization by chemical reaction in transfer-mass spectrometry (SICRIT-MS). SICRIT is a flow-through dielectric barrier discharge ionization technique pioneered by Zenobi et al. in 2016. The electric soldering iron cauterization-SICRIT-MS method requires no sample pretreatment, easy operation and a single analysis in less than 5 s, meeting the demands of rapid analysis. Operating parameters for the soldering iron and SICRIT ion source were optimized to achieve maximum total ion current intensity under soldering iron temperature of 450℃, ion source AC voltage amplitude of 2000 V, and sample transfer line temperature of 150 ℃. With the optimized parameters, the SICRIT-MS method was applied to analyze valuable wood samples, including 29 certified standard wood samples and 6 online-purchased real samples, resulting in a dataset of 210 sets of mass spectral fingerprint data. Based on the mass spectral fingerprint data acquired under positive ion mode, a predictive model was trained using the random forest algorithm. The random forest model underwent optimization for the number of decision trees, max feature algorithm, and feature selection criteria, was evaluated through out-of-bag and 10-fold cross-validation. The results showed the error rates of out-of-bag and 10-fold cross-validation are 4.76% and 4.74%, respectively. The established random forest model can accurately distinguish wood samples from the genera Dalbergia, Guibourtia, and Pterocarpus with a classification accuracy of larger than 95%. The importance of features in distinguishing the three wood genera was investigated through binary classification modeling, revealing features 269.1, 270.1, 255.1, 159.0, 182.1, 102.1 and 83.1 as crucial in classification. These features may correspond to characteristic compounds in different wood species or differences in the content of the same compound across species. The predictive model was successfully applied to rapid identification of genera in valuable wood products sold online. Three purchased Guibourtia samples are confirmed as authentic, while the other three are not identified as the claimed genera. This method provides a scientific basis and experimental reference for authenticity identification and quality evaluation. [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 Journal of Beijing International Studies University is the property of Beijing International Studies University 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 Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office 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 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 Mental Health Journal / Zhongguo Xinli Weisheng Zazhi is the property of Chinese Mental Health Journal 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 Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office 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 Acta Agronomica Sinica is the property of Crop Science Society of China 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 Journal of Technology Economics is the property of Chinese Society of Technology Economics 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 Journal of Mine Automation is the property of Industry & Mine Automation 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 Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office 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.)

Naturally-occurring precipitate of traditional Chinese medicine (TCM) is generally considered to be a common phenomenon. The formation of naturally-occurring precipitate originates from the interactions among different chemical components during the decoction process. Previous literature has reported the existence of naturally-occurring precipitate in Sini decoction. In this study, seven pairs of acid-base non-covalent complexes in Sini decoction were characterized using cold spray ionization-mass spectrometry (CSI-MS) . The CSI device was built in house, where a stream of nitrogen gas was cooled by liquid nitrogen and used as the sheath gas, providing low-temperature ionization conditions for the MS analysis of the acid-base non-covalent complexes. The gas pipeline was equipped with a valve to regulate the nitrogen flow rate. Data acquisition was carried out using a quadrupole/Orbitrap high-resolution mass spectrometer operated in both full-scan MS and collision-induced dissociation MS/MS modes. Experimental results showed that the seven pairs of acid-base non-covalent complexes were unequivocally observed in positive and negative ionization modes. Mass spectrometric responses for each acid-base non-covalent complex varied with different chemical structures, binding abilities and ionization efficiencies. A representative pair of acid-base non-covalent complex (enoxolone/benzoylmesaconine) was selected to investigate the influence of the acid-base concentration ratio (3∶1, 2∶1, 3∶2, 1∶1, 2∶3, 1∶2, 1∶3) on the binding stoichiometry. The enoxolone/benzoylmesaconine complexes with the binding ratios of 1∶1, 1∶2, 2∶1 were observed, among which the mass spectrometric peak of the 1∶1 binding ratio was the most intensive. The non-covalent interactions of the representative enoxolone/benzoylmesaconine complex were analyzed using isothermal titration calorimetry (ITC) and computational chemistry. The thermodynamic parameters were obtained in the ITC experiment. In comparison with entropy change, the contribution of enthalpy change to Gibbs free energy was more significant, indicating that Van der Waals force and hydrogen bonding might be the main driving force in the formation of acid-base non-covalent complexes. This result was further confirmed by the docking model and simulation results of computational chemistry. Multiple hydrogen bonds derived from the interactions between specific atoms locating in the acid and base compounds promoted the self-assembly process. Moreover, Van der Waals attraction or repulsion force was generated between the C and H atoms at different positions, which in conjunction with hydrogen bonding interaction drove the formation of the acid-base non-covalent complexes. This study provides theoretical foundation and technical instruction for exploring the formation mechanism of naturally-occurring precipitate in Sini decoction. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office 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 Applied Mathematics & Mechanics (1000-0887) is the property of Applied Mathematics & Mechanics 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 Food Science & Technology & Economy is the property of Grain Science & Technology & Economy Editorial Office 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 Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of 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.)

Copyright of Journal of Chinese Mass Spectrometry Society is the property of Journal of Chinese Mass Spectrometry Society 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 Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications 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 China Forestry Economy is the property of China Forestry Economy Magazine Agency 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.)

[Objectives] We evaluated the effects of soil waterlogging on growth, root morphology and grain yield of wheat. [Methods] Wheat cultivars Ningmai 13 and Wanmai 52' were used. At anthesis, potted plants were shifted in a water-filled container for different duration (0,3,6 and 9 d. as W0. W3, W6 and W9, respectively). [Results] Short-term waterlogging (W3) had no significant effect on the growth and yield of wheat cultivars. However, long-term waterlogging W6 and W9 significantly reduced total root length, average root diameter, root dry matter weight, total volume and total surface area of both wheats. Increasing waterlogging durations significantly increased malonaldehyde(MDA) content and peroxidase (POD) activity in the root tissues of wheat cultivars measured at 7,14 and 21 days after anthesis. W6 and W9 treated plants had a significantly lower root superoxidase dismutase (SOD) than that of WO at 21 days after anthesis. W6 and W9 significantly reduced total plant dry biomass, harvest index, thousand kernel weight and total gain yield total surface area measured at 21 days after anthesis. [Conclusions]Short-term waterlogging had no significant effect on root morphology, I of the two wheat cultivars at maturity. In addition, kernels per spike were significantly reduced by waterlogging (W6 and W9) in cultivar Wanmai 52' only. Wheat grain yield at maturity had significant positive correlation with total dry matter weight, total root volume and dry matter allocation above the ground and the yield in both of wheat cultivars. While, long-term waterlogging significantly affected root morphology in both cultivars used in this study, with no significant growth recovery up to 21 days after anthesis. Then long-term water logging reduced the dry weight of grain and the proportion of grain dry weight above ground that ultimately led to yield penalties. [ABSTRACT FROM AUTHOR]

Fentanyl is a synthetic opioid with strong anesthetic and analgesic properties. A significant challenge for the legislative control of fentanyl abuse is the ever-growing list of emerging derivatives. New fentanyl analogues have been constantly synthesized by alterations to the fentanyl structure to circumvent regulatory oversight and avoid laboratory scrutiny. Therefore, the reliable identification of fentanyl analogues is of great significance for public security. In this study, the tandem mass spectrometry (MS/MS) data for 46 fentanyl analogues were acquired using dielectric barrier discharge ionization mass spectrometry (DBDI-MS), and their fragmentation pathways were further investigated. The fentanyl analogues were subjected to the ionization of both DBDI and electrospray ionization (ESI). Despite a lower overall ion intensity, DBDI produced more characteristic fragment ions, providing comprehensive structural information for the identification of fentanyl analogues. Abundant protonated molecules were readily observed for fentanyl analogues in the positive ionization mode. The protonated fentanyl compounds were chosen as precursor ions for subsequent collision-induced dissociation (CID). Structurally similar compounds generally exhibit consistent fragmentation behavior during the MS/MS analysis. Characteristic fragment ions at m/z 105 and m/z 188 were observed for two important fentanyl precursors (N-phenethyl-4-piperidone and 4-anilino-N-phenethylpiperidine). When structural substitution occurred on the phenethyl group or piperidine ring of fentanyl, a neutral loss of 149 u could be found, indicating the cleavage of the C—N bond at the 4′ position of piperidine ring and the generation of N-phenylpropionamide. On the other hand, the substitution at the N-propionyl or N-phenyl group led to the formation of a fragment ion at m/z 188, corresponding to N-phenethyl-4-piperidine cation. Therefore, the 46 fentanyl analogues investigated were categorized into two groups according to their fragmentation patterns. Moreover, a rapid method was developed for the analysis of fentanyl in powder samples using DBDI-MS. Good linearity was obtained in the concentration range of 1-20 mg/kg (r=0.999 3). The limit of detection (LOD) and quantification (LOQ) for fentanyl were 0.3 and 1 mg/kg, respectively, with the relative standard deviations (RSDs) less than 2.6%. The current study demonstrates a promising potential for reliable screening of fentanyl analogues with enhanced operation simplicity, analysis speed, and detection throughput. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics Editorial Office 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 Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office 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 Journal of Mine Automation is the property of Industry & Mine Automation 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 Applied Mathematics & Mechanics (1000-0887) is the property of Applied Mathematics & Mechanics 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 Journal of Nanjing Normal University / Nanjing Shi Da Xue Bao (She Hui Ke Xue Ban) is the property of Nanjing Shifan Daxue 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 Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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 Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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.)