TALANTA
·
2024
·
IF 5.6
Xu Zhang,Yuanjiang Luo,Lei Xia,Yu Song,Wanjun Li,Lingwen Kong,Yawei Liu,Chengyin Shen,Chaoqun Huang,Yannan Chu
2,4,6-Trinitrotoluene (TNT) and its four metabolites, namely 2-ADNT, 4-ADNT, 2,4-DANT, and 2,6-DANT, are highly toxic substances. These metabolites also serve as biomarkers for assessing the health of individuals exposed to TNT. In this study, a homemade DDT-IMS apparatus was utilized to detect these metabolites. Under negative detection mode, the drift times of 2-ADNT and 4-ADNT showed subtle shifts within a drift tube temperature range of 100 °C–120 °C, aiding in their differentiation. In positive detection mode for 2,4-DANT and 2,6-DANT, significant variations were observed in both the number and drift time of their positive product ions across a drift tube temperature range of 80 °C–120 °C. Consequently, optimal analytical performance for these metabolites was achieved at approximately 100 °C. Evaluation of the instrumental response during the measurement of the four metabolites in both positive and negative modes revealed that negative detection mode offered greater advantages of detecting these compounds. The working ranges for measuring the four metabolites spanned two orders of magnitude, with detection limits for each metabolite nearly below 1 ng. Notably, clear identification of the signals for these metabolites was achieved even when samples were mixed in urine, highlighting the ability of the DDT-IMS in detecting TNT metabolites. The developed DDT-IMS detection method has significant potential for enhancing environmental risk assessment and biological hazard evaluation, particularly in relation to human exposure to TNT.
研究领域:
环境科学
·
分析化学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Lingcong Li,Xiaojun Liu,Hong He,Ningqiang Zhang,Ziwen Liu,Guizhen Zhang
The MgO-doped hexagonal boron nitride (MgO-h-BN) nanomaterials were designed as a support for Palladium (Pd) catalysts for CO oxidation reaction. The catalytic properties of Pd/MgO(5)-h-BN catalyst was investigated and compared with Pd/h-BN catalyst. Transmission electron microscopy (TEM) results suggested that the PdO nanoparticles with small grain sizes (ca. 8 nm) were effectively dispersed on the surface of MgO, and the MgO were deposited on the h-BN nanosheets in the Pd/MgO(5)-h-BN catalyst. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses revealed that a small amount of Mg 2+ embedded into the B vacancies of h-BN nanosheets in the Pd/MgO(5)-h-BN catalyst. More significantly, a large amount of adsorbed oxygen appeared near the B vacancies of Pd/MgO(5)-h-BN catalyst. The experiments outcomes of diffuse reflectance fourier transform spectra analysis of CO (CO-DRIFT) indicated that the carbonate/formate species were easily decomposed to CO 2 on the Pd/MgO(5)-h-BN catalyst than Pd/h-BN catalyst, which might be a reason why the Pd/MgO(5)-h-BN catalyst had high CO oxidation activity. According to above analyses, we provide a new insight for the MgO-h-BN nanomaterials for Pd catalysts for application in CO oxidation reaction.
研究领域:
催化
·
材料科学
·
化学
·
纳米技术
✓ 已验证
DOI
高影响因子
COMPUTERS AND ELECTRONICS IN AGRICULTURE
·
2026
·
IF 8.9
Pengchao Chen,Jiapei Wu,Zhihao Bian,Jean Paul Douzals,Yingdong Qin,Hanbing Liu,Juan Wang,Yubin Lan
Unmanned aerial spraying systems (UASS) are widely used in agriculture; however, spray drift remains a significant barrier to their broader adoption. Conventional drift-control measures—such as nozzle optimization and adjuvants—primarily act by altering droplet size. This study introduces a dynamic droplet-size control approach for UASS equipped with centrifugal nozzles to balance spray quality and drift risk. We established the relationship between nozzle rotational speed and droplet size and developed an embedded, variable droplet-size UASS. The system utilizes differential RTK to acquire real-time UAV position data, enabling dynamic adjustment of droplet size during operation. Field trials demonstrated the system’s stability and reliability: the UASS responded promptly to ground commands for droplet size changes and accurately logged the corresponding adjustment locations. Data analysis indicated that increasing droplet size markedly reduces drift volume and droplet density in the downwind drift zone. Relative to a baseline without droplet-size control, a three-stage adjustment strategy reduced the drift ratio by 89.18%, shortened the 90% drift distance to 3.36 m, and delivered the highest drift-mitigation rate. To minimize drift while maintaining effective penetration, we propose using the very fine (VF) droplet size (82.4 μm) for the first two flight paths and increasing to 300–350 μm for the third. These findings demonstrate that dynamic droplet-size adjustment via pulse-width modulation can effectively reduce drift. External factors, such as wind and terrain, continue to be influential, underscoring the need for further research to refine and optimize drift-control strategies under diverse operating conditions.
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2017
·
IF 4.95
Ruo-Jing Fan,Fang Zhang,Xiu-Ping Chen,Wan-Shu Qi,Qing Guan,Tuan-Qi Sun,Yin-Long Guo
The present work focused on the high-throughput screening and quantitation of guanidino compounds (GCs) and ureido compounds (UCs) in human thyroid tissues. The strategy employed benzylic rearrangement stable isotope labeling (BRSIL) for the sample preparation and then detection using liquid chromatography-drift tube ion mobility spectrometry-quadrupole time of flight mass spectrometry (LC-DTIMS-QTOF MS). A short reversed-phase LC realized an on-line desalting and a measurement cycle of 5.0 min. DTIMS separation enhanced the better specificity and selectivity for the benzil labeled GCs and UCs. The elevated mass resolution of QTOF MS enabled measure of the characteristic ions at accurate mass in MS and tandem MS spectra. Collision cross section (CCS) from DTIMS and accurate mass from QTOF MS were used as two qualifiers for the profiling and identification of GCs and UCs. In addition, an integral abundance arising from 3-D ion features (retention time, drift time, m/z ) was applied to quantify the GCs and UCs in human thyroid tissues. The quantitative validation indicated good linearity (coefficient values ≥ 0.9981), good precision (1.0%–12.3% for intra-day and 0.9%–7.8% for inter-day) and good accuracy (91%–109%). The results demonstrated that the developed BRSIL coupled with LC-DTIMS-QTOF MS can be a powerful analysis platform to investigate GCs and UCs in human thyroid tissues.
研究领域:
分析化学
·
医学
·
代谢组学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Ming Zhang,Dingqiang Zheng,Lei Shi,Chaoyang Zhang,Hongyang Fei,Weixing Huang,Xuetao Hu
To generate clean freshwater controllably and efficiently, Fe 3 O 4 /CNT nanomaterials and hydrophobic PVDF were introduced to delignified wood with man-made-cutting structure (D-Wood) in simple brushing method for constructing the magnetic and photothermal wood evaporator with asymmetric wettabilities and wind drift resistance. Such method could endow wood with various shapes design, outstanding magnetically sensitivity, remarkable photothermal conversion efficiency (129.08 %), high evaporation rate (1.92 kg·m −2 ·h −1 ), good dye degradability (97.23 %), and excellent wind resistance (6.6 m/s). The superhydrophilic and underwater superoleophobic bottom of Fe 3 O 4 /CNT/PVDF@D-Wood evaporator accelerated the bulk seawater transport during its evaporation procedure, but prevented the oil pollutants blocking the microchannels of evaporator during the long periods of flotation at sea. Meantime, its hydrophobic top could effectively reduce the downward diffusion of heat, and improve the salt tolerance. After 10 cycles of acid-base, ultrasound treatments and evaporating experiments, Fe 3 O 4 /CNT/PVDF@D-Wood evaporator still exhibited excellent evaporation rate and conversion efficiency, displaying remarkable repeatability and long-term durability. In weak magnetic field (3 V), its furthest response displacement and time were 5 cm and 41 s, respectively. After prolonged evaporation procedure, the magnetic responsivity of Fe 3 O 4 /CNT/PVDF@D-Wood evaporator could be in almost constant level, which offers a promising biomass product for seawater desalination and polluted-water purification.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2017
·Vol. 19
·期 7
·5333-5342
·
IF 4.123
Shu-xian Wang,Rui-tang Guo,Wei-guo Pan,Ming-yuan Li,Peng Sun,Shu-ming Liu,Shuai-wei Liu,Xiao Sun,Jian Liu
It was well recognized that Pb had a poisoning effect on a SCR catalyst. In this study, the deactivation mechanism of Pb on the Ce/TiO2 catalyst was investigated based on the characterization results of TPD and in situ DRIFT studies. It was found that the addition of Pb on the Ce/TiO2 catalyst not only inhibited the adsorption and activation of NH3 species, but also led to the decrease of the activity of adsorbed NH3 species in the SCR reaction. The adsorption of NOx species and the oxidation of NO by O2 over the Ce/TiO2 catalyst were also suppressed by the addition of Pb, while the reactivity of adsorbed NO2 species did not decrease. Moreover, the results revealed that the NH3-SCR reaction over the Ce/TiO2 catalyst followed both the E–R and L–H mechanisms, while the NH3-SCR reaction over Ce/TiO2-Pb was mainly controlled by the L–H mechanism. The contributions of the L–H mechanism to the SCR reactions over Ce/TiO2 and Ce/TiO2-Pb decreased with increasing reaction temperature. The deactivation of Ce/TiO2-Pb was mainly attributed to the suppressed NH3 adsorption and activation, accompanied by the inhibited NO oxidation and the decrease of Brønsted acid sites.
研究领域:
环境催化
·
大气污染控制
·
材料化学
·
表面科学
·
物理化学
✓ 已验证
DOI
高影响因子
Frontiers in Plant Science
·
2022
·
IF 6.627
Li Longlong,Hu Zhihong,Liu Qingju,Yi Tongchuan,Han Ping,Zhang Ruirui,Pan Ligang
Extensive research has been conducted on plant protection unmanned aerial vehicle (UAV) chemical application technology in recent years owing to its importance as a means of pest and disease control. UAV spraying in orchards faces the drawback of drift risk and can be hazardous to non-targeted crops, humans, and the environment. A detailed and systematic analysis must be performed to determine the uniformity and drift risk of plant UAV sprays. In this study, a peach orchard is sprayed with a plant-protection UAV at three different flight velocities and we evaluate the combined pesticide deposition performance of the canopy, ground loss, downwind ground drift, and airborne drift. Additionally, the droplet size and coverage rate in the canopy are calculated by using water-sensitive paper. The results demonstrate that there is significant difference in the droplet size at flight velocities of 1–3 m/s. The droplet size in the lower canopy is slightly smaller than those in the middle and upper parts. Increasing the flight velocity helps the pesticide droplets to spread and penetrate the canopy. However, it also causes a non-uniform pesticide deposition, reduced effective coverage ratio and effective density ratio. Among the three pesticides used in the experiment, imidacloprid exhibits the best deposition efficiency. The deposition amount and normalized deposition amount in the canopy were the highest at a flight velocity of 2 m/s, accompanied by a lower ground loss under the canopy. The highest near-field ground drift is observed at a velocity of 1 m/s, and the far-field airborne drift is highest at 3 m/s. Lastly, this study provides a reference for the commercial application of plant-protection UAVs.
研究领域:
农业科学
·
植物保护
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Yanyu Jin,Hongjun Cheng,Qibao Wang,Xiaoqing Liu,Shengpeng Mo,Bin Zhou,Yue Peng,Yu Wang,Wenzhe Si,Junhua Li
An depth understanding of the fundamental interactions between surface termination and catalytic activity is crucial to prompt the properties of functional perovskite materials. The elastic energy due to size mismatch and electrostatic attraction of the charged Sr dopant by positively charged oxygen vacancies induced inert A-site surface enrichment rearrangement for perovskites. Lower temperatures could reduce A-site enrichment, but it is difficult to form perovskite crystals. La 0.8 Sr 0.2 CoO 3-δ (LSCO) as a model perovskite oxide was modified with additive urea to reduce the crystallization temperature , and suppress Sr segregation. The LSCO catalysts with 600 °C annealing temperature (LSCO-600) exhibited a 19.4-fold reaction reactivity of toluene oxidation than that with 800 °C annealing temperature (LSCO-800). Combined surface-sensitive and depth-resolved techniques for surface and sub-surface analysis, surface Sr enrichment was effectively suppressed due to decreased oxygen vacancy concentration and smaller electrostatic driving force. DFT calculations and in-situ DRIFTs spectra well revealed that tuning the surface composition/termination affected the intrinsic reactivity. The catalyst surface with lower Sr enrichment could easily adsorb toluene, cleave, and decompose benzene rings , thus contributing to toluene degradation to CO 2 . This work demonstrates a green and efficient way to control surface composition and termination at the atomic scale for higher catalytic activity.
研究领域:
材料科学
·
催化
·
表面科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 86
·82707-82715
·
IF 3.289
Wei Li,Rui-tang Guo,Shu-xian Wang,Wei-guo Pan,Qi-lin Chen,Ming-yuan Li,Peng Sun,Shu-ming Liu
A series of Mn/CeSiOx catalysts were prepared by the wet impregnation method and used for selective catalytic reduction of NO with NH3. As can be seen from the experimental results, the Mn/CeSiOx catalyst with a Ce/Si molar ratio of 2/1 showed excellent low-temperature SCR activity, high N2 selectivity and excellent SO2 and H2O tolerance. The relationship between the CeSiOx support and the SCR performance of Mn/CeSiOx (2 : 1) catalyst was investigated based on the characterization results of N2 adsorption, XRD, XPS, H2-TPR, NH3-TPD and in situ DRIFT. The strong interaction between Ce and Si resulted in the good dispersion of Mn species on the support; correspondingly, the redox ability and NH3 adsorption capacity were greatly enhanced. The results of in situ DRIFT study revealed that the NH3-SCR reactions over Mn/CeO2 and Mn/CeSiOx (2 : 1) mainly obeyed both the E–R mechanism and the L–H mechanism. Furthermore, the formation of more Mn4+ and chemisorbed oxygen greatly facilitates the oxidation of NO to NO2, as a result, promoting the low-temperature SCR performance of Mn/CeSiOx (2 : 1).
研究领域:
催化
·
环境科学
·
化工
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）