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Underflow concentration prediction model of deep-cone thickener based on data-driven

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The Journal of China Universities of Posts and Telecommunications 2019年第6期26卷 63-72页

作者： Wang Huan LIU TING Cao Yuning Wu Aixiang School of Civil and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China

The underflow concentration prediction of deep-cone thickener is a difficult problem in paste filling. The existing prediction model only determines the influence of some parameters on the underflow concentration, but lacks a prediction model that comprehensively considers the thickening process and various factors. This paper proposed a model which analyzed the variation of the underflow concentration from a number of influencing factors in the concentrating process. It can accurately predict the underflow concentration. After preprocessing and feature selection of the history data set of the deep-cone thickener, this model uses the eXtreme gradient boosting(XGBOOST) in machine learning to deal with the relationship between the influencing factors and the underflow concentration, so as to achieve a more comprehensive prediction of the underflow concentration of the deep-cone thickener. The experimental results show that the underflow concentration prediction model based on XGBOOST shows a mean absolute error(MAE) of 0.31% and a running time of 1.6 s on the test set constructed in this paper, which fully meet the demand. By comparing the following three classical algorithms: back propagation(BP) neural network, support vector regression(SVR) and linear regression, we further verified the superiority of XGBOOST under the conditions of this study.

关键词： paste filling underflow concentration machine learning XGBOOST prediction model

Silencing of transcription factor E93 inhibits adult morphogenesis and disrupts cuticle, wing and ovary development in Locusta migratoria

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Insect Science 2022年第2期29卷 333-343页

作者： Xiao-Jian liu Guo Jun Xiao-Yu Liang Xue-Yao Zhang ting-ting Zhang Wei-Min liu Jian-Zhen Zhang Min Zhang Research Institute of Applied Biology Shanxi UniversityTaiyuanChina

Ecdysone-induced protein 93F(E93)plays important roles during the metamorphosis process in insects.In this study,a cDNA of the LmE93 gene was identified from the transcriptome of Locusta migratoria,which consists of the 3378-nucleotide open-reading frame(ORF)and encodes 1125 amino acids with helix–turn–helix(HTH)motifs.Reverse transcription quantitative polymerase chain reaction analysis revealed that LmE93 was highest expressed in ovary.The LmE93 expression level was markedly low from the 3rd to 4th instar nymphs,and greatly increased in 1-day-old 5th instar nymphs with a peak on middle nymphal days,then declined in the late nymphal days.Moreover,injected dsLmE93 into 4th and 5th instar nymphs greatly reduced LmE93 transcripts,respectively,and prevented the process of metamorphosis,causing supernumerary nymphal stages.Hematoxylin–eosin staining of the integument showed that the apolysis occurred in advance in 4th instar nymphs,and old cuticle degradation was decreased in dsLmE93-injected locusts of 5th instar nymphs.Smaller and no fully developed wings with reduced columns between the anterior and posterior regions were found in N6 and N7 supernumerary nymphs.In addition,the development of the ovary in dsLmE93-injected locusts was severely blocked,the yolk was almost not formed and there was no development of ovarioles.The results indicated that LmE93 play key roles in the metamorphosis,cuticle,wing and ovarian development of locusts.

关键词： expression function Locusta migratoria RNA interference transcription factor E93

Effect of Particle Size on Target Sintering Behavior of Cubic ITO Nanopowders

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Journal of Wuhan University of Technology(Materials Science) 2020年第6期35卷 1098-1103页

作者： ZHAI Xiaoyu PENG Xiang MA Yunqian LIU TING 刘家祥 Beijing Key Laboratory of Electrochemical Process and Technology for Materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

The effect of particle size on the density and resistivity of ITO green bodies and targets was systematically investigated.The experimental results show that the relative density of ITO green bodies decreases with the increase of ITO particle size.When the particle size is 10.7 nm,the relative density of ITO green bodies rises to the maximum value of 56.6%.The resistivity declines exponentially with the increase of particle size,which satisfies the exponential equation of R=exp(-41.823 × d).When the particle size is 41.6 nm,the resistivity reaches the minimum value of 0.8 Ω·cm.The relative density of ITO target decreases with the increase of particle size.Fine particles can increase the driving force of densification in initial stage.Electron mobility,caused by grain boundary scattering,will increase due to the increase of particle size or the decrease of grain boundary potential.When the particle size is 10.7 nm,the target with compact grain stacking and low porosity shows a maximum relative density of 99.25%,and the resistivity reaches the minimum value of 0.34×10^-3 Ω·cm.

关键词： indium tin oxide nanoparticles particle size indium tin oxide target relative density resistivity

饮用水处理过程中全氟化合物的分布、转化及去向

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环境科学 2023年第5期44卷 2613-2621页

作者：钟婷婷林涛刘威河海大学浅水湖泊综合治理与资源开发教育部重点实验室南京210098 河海大学环境学院南京210098

全氟和多氟烷基物质(PFASs)存在于地表水、自来水甚至商业饮用水中,对人类健康构成威胁.在以太湖为源头的某大型饮用水处理厂(DWTPs)中研究了14种PFASs的检出和转化.结果表明,共有10种PFASs在水样中被检测到,说明PFASs在饮用水中分布广... 详细信息

全氟和多氟烷基物质(PFASs)存在于地表水、自来水甚至商业饮用水中,对人类健康构成威胁.在以太湖为源头的某大型饮用水处理厂(DWTPs)中研究了14种PFASs的检出和转化.结果表明,共有10种PFASs在水样中被检测到,说明PFASs在饮用水中分布广泛.原水中的PFASs总浓度为127.4ng·L^(-1),其中最高浓度为全氟辛酸(PFOA,49.8ng·L^(-1)).预臭氧会导致PFASs的浓度反向升高,这可能是由于前体物的存在或由短链向长链进行转化导致.常规处理工艺无法有效去除PFASs,O_(3)-BAC在DWTPs的处理过程中对PFASs的去除(20.74%)具有主导作用.O_(3)-BAC作为DWTPs的主要去除工艺,其反冲洗水中含有浓度较高的PFASs,分布特征与原水相似.利用中试装置,对比了5种常见的滤池反冲洗水处理工艺,结果表明,GAC-超滤可以在保证浊度较高去除率(99.08%)的基础上,吸附并截留一定量的PFASs.从三维荧光分析可得,GAC-超滤也可去除大部分荧光微污染物,对于原水含有较高浓度的PFASs的DWTPs来说,将其作为滤池反冲洗水回用处理工艺是实际可行的.

关键词：饮用水处理全氟和多氟烷基物质(PFASs) 滤池反冲洗水超滤三维荧光(3D-EEM)

Overshoot phenomena:Observation and simulation

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Earth and Planetary Physics 2024年第2期8卷 391-399页

作者： ting Feng MoRan liu ShiMin He Xiang Wang Chen Zhou Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

High-power O-mode radio waves can excite artificial instabilities in the F region,according to experiments conducted at the European Incoherent Scatter Science Association(EISCAT)heating facility.The main instabilities include the parametric decay instability(PDI),oscillating two-stream instability(OTSI),and thermal parametric instability(TPI).The PDI and OTSI not only compete with each other,but also compete with the TPI,leading to a two-stage overshoot phenomenon:a miniovershoot occurs on a millisecond time scale after pump-on,followed by the main overshoot.We gain insight into the miniovershoot via a generalized Zakharov model,whereas the main overshoot can be observed as an enhanced plasma line overshoot phenomenon in incoherent scatter radar spectra.We can also observe that the zero-frequency ion line exists only in the initial heating period after a cold start and that the upshifted and downshifted ion lines behave irregularly in the spectra.The simulation results show that competition between the PDI and OTSI leads to an initial peak,which we named the pre-miniovershoot.The following processes,namely ion density caviton generation,and collapse and cascade in the development of the PDI,contribute to the miniovershoot phenomenon.

关键词： overshoot parametric decay instability oscillating two-stream instability competition

Effects of Emotion on Decision-Making ofMethamphetamine Users: Based on theEmotional Iowa Gambling Task

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International Journal of Mental Health Promotion 2023年第11期25卷 1229-1236页

作者： Xiaoqing Zeng Song Tu ting liu School of Psychology Jiangxi Normal UniversityNanchang330022China Jiangxi Key Laboratory of Psychology and Cognitive Science Nanchang330022China Institute of Psychology Jiangxi Normal UniversityNanchang330022China Shenzhen Daydream Network Technology Co. Ltd.Shenzhen518000China

The relapse of methamphetamine (meth) is associated with decision-making dysfunction. The present study aims to investigate theimpact of different emotions on the decision-making behavior of meth users. We used 2 (gender: male, female) × 3 (emotion:positive, negative, neutral) × 5 (block: 1, 2, 3, 4, 5) mixed experiment design. The study involved 168 meth users who weredivided into three groups: positive emotion, negative emotion and neutral emotion group, and tested by the emotional IowaGambling Task (IGT). The IGT performance of male users exhibited a decreasing trend from Block 1 to Block 3. Female methusers in positive emotion had the best performance in IGT than females in the other two groups. In positive emotion, the IGTperformance of female meth users was significantly better than that of men. Female meth users in positive emotion had betterdecision-making than those in negative or neutral emotion. Female meth users in positive emotion had better decision-makingperformance than males in positive emotion. In negative and neutral emotions, there was no significant gender difference indecision-making.

关键词： Methamphetamine user emotion gender difference Iowa gambling task decision-making

Evaluation of groundwater geochemical characteristics and quality in the central and Northern Shaanxi Province,China

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Acta Geochimica 2020年第5期39卷 733-740页

作者： Hui Yan Jun Xiao ting liu Yujie liu College of Urban-Rural Planning and Landscape ArchitectureXuchang UniversityXuchang 461000China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment.Chinese Academy of SciencesXi'an 710061China CAS Center for Excellenee in Quaternary Science and Global Change Xi'an 710061China College of Geomatics Xi'an University of Science and TechnologyXi'an 710054.China

Groundwater is of vital importance to many aspects of ecosystem services,especially in the central and northern Shaanxi Provence,China,-an area covered by loess deposits and short of water resources.We studied the solute geochemistry and water quality of groundwater in this area to improve the understanding of hydrogeochemical processes in loess deposits area.The results showed that the average pH of groundwaters was 8.03±0.36(1 SD)with large ranges(324-83,379 mg/L)of the total dissolved solids(TDS).The cations and anions followed the order of Na^+>Ca^2+>Mg^2+>K^+>SiO2 and HCO3>Cl^->SO4^2->F^->NO3^-.Most groundwater samples show the HCO3^--Na^+-Ca^2+water type and a small number of samples the Na^+-Cl^-type.Irrigation water quality assessments showed that 40%of the groundwater has good water quality,42%moderate water quality,and 18%(the upper reaches of Wuding River and Wei River)poor water quality with very high salinity.About 40%of groundwater samples were not suitable for drinking due to the high TDS,fluoride,sulfide,and chloride.Gibbs plot and stoichiometry analysis showed that carbonate weathering is the main source of groundwater chemistry in central Shaanxi Province while evaporite dissolution dominates in northern Shaanxi Provence.The loess weathering significantly influences the dissolved solutes of groundwater in the Loess Plateau.The ion-exchange between Mg^2+and Ca^2+in groundwater and Na^+in clay minerals and the deposition of carbonate minerals increased Na^+but decreased the Ca^2+in groundwater.Our research results improve our understanding of hydrogeochemical processes that affect the solutes chemistry of groundwater in the loess area and provide essential data to the global groundwater database.

关键词： Geochemical characteristics Hydrochemical process Groundwater quality Central and northern Shaanxi

How does the host-specialized aphid deal with food deficiency？

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Insect Science 2014年第3期21卷 334-341页

作者： ting-ting Xu ting-ting Ma Xiang-Dong liu Department of Entomology Nanjing Agricultural University Nanjing China

Aphis gossypii Glover shows obvious host specialization, with cucurbit- and cotton-specialized biotypes or host races in many regions. Because its annual natal hostcrops senesce earlier the cucurbit-specialized biotype may suffer food deficiency. The method this biotype uses to overcome this challenge is still poorly understood. In orderto understand the potential of the cucurbit-specialized biotype aphids in host shift and usage, the performance of this biotype on cotton （Gossypium hirsutum）, a common butpoor quality host plant, was explored in this study. The cucurbit-specialized aphids could establish populations on cotton only when these plants had at least nine leaves, and subsequent populations developed rather slowly. The presence of whitefly populations on cotton improved the success rate of cucurbit-specialized aphids. The cucurbit-specialized aphidswere mainly distributed on the older leaves of cotton, with only a few settling on the upper leaves. The cucurbit-specialized aphids reared on cotton for 40, 54 and 61 days stillmaintained strong preference for their natal host plant, cucumber （Cucumis sativus）, rather than cotton, and their net reproductive rates and intrinsic rates of natural increase weredramatically lower when they were transferred onto new six-leaf cotton plants or detached leaves. Therefore, we concluded that the cucurbit-specialized aphids have the potentialto utilize mature or whitefly-stressed cotton plants, but that this feeding experience on cotton did not alter their specialization for cucurbits. Some cotton plants could act as atemporary host for the cucurbit-specialized aphids to overcome food deficiency arising from senescing cucurbits.

关键词： Aphidgossypii cotton-melon aphid host shift host specialization temporary host whitefly-stressed cotton

Copper-coated Porous Polyimide as Ultralight and Safe Current Collectors for Advanced LIBs

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Chinese Journal of Polymer Science 2024年第4期42卷 521-531页

作者： Cun-Sheng liu Jun-Qi Hu ting-ting Mao Song-Yi Liao Ru-Ming Feng Yi-Dong liu Yong-Gang Min School of Materials and Energy Guangdong University of TechnologyGuangzhou510006China College of Chemistry and Chemical Engineering Zhongkai University of Agriculture and EngineeringGuangzhou510225China Shanwei Branch of Advanced Energy Science and Technology Guangdong Laboratory Shanwei516600China

Metallic copper is widely used as current collector(CC) for graphite anode of lithium-ion batteries(LIBs) due to its high electrical conductivity and electrochemical stability. However, the large volume density of commercial copper foil(~8.9 g·cm^(-3)) limits the increase of energy density of battery. Here, copper-coated porous polyimide(Cu@PPI) was prepared by vacuum evaporation as collector for the graphite anode. The sandwich structure connects the copper metal on both sides of the collector with excellent electrical conductivity. Compared to commercial Cu foil, Cu@PPI has lighter mass(≤3.9 mg for disc of 12 mm diameter versus 9.9 mg of ~10 μm Cu foil) and lower volume density(≤3.3 g·cm^(-3)). In addition, the porous structure allows of better adhesion of reactive substances and electrochemical properties than pure Cu foils. It is estimated that the energy density of Cu@PPI should be much higher than that of Cu foil. This strategy should be applicable for other current collectors.

关键词： Copper-coated Vacuum evaporation Porous polyimide(PPI) Current collector(CC) LIBs