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Phosphorus accumulation and eutrophication in feed-supply freshwater fishponds

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Journal of Environmental Sciences 2006年第4期18卷 816-821页

作者： ZHANG Ming-kui FANG li-ping Institute of Soil and Water Resources and Environmental Science College of Natural Resource and Environmental Sciences Zhejiang UniversityHangzhou 310029 China

The rapid growth and intensification of freshwater fishery can cause imbalances between phosphorus （P） input in feed and its output in produce. This aquaculture can result in enriching exogenous P in fishponds and, consequently, accelerates the process of eutrophication. To assess relations among input, accumulation, release of P and as a consequence degrading water quality in terms of chlorophyll-a （Chl-a） in freshwater fishponds, fourteen fishponds with feed supply, nine fishponds without feed supply, and five nonfish ponds in Shaoxing Plain, southeast China were selected for comparing P accumulation in their waters and surface sediments. Surface sediment samples were collected from each pond to evaluate their total P, water soluble P, Olsen P, algal available P, and P fractions. Water samples were also collected from the ponds to measure concentrations of dissolved P and Chl-a. Total P in the sediments ranged from 0.88 to 1.73 g/kg in the fishponds with feed supply, that in the non-fish ponds ranged from 0.47 to 0.86 g/kg. Organic P, accounted for 23% to 60% of total P in the sediments, was an important P fraction and increased linearly with increasing organic matter. Long-term application of feeds resulted in increased P availability in the bottom sediments and degradation of water quality in the freshwater fishponds. Compared with non-fish ponds, sediments from the feed-supplied fishponds contained considerably higher Olsen P, algal available P, and water soluble P. Higher proportions of the labile P （NH4Cl-P） and potentially labile P （NaOH-IP） were also found in the sediments from the fishponds. High solubility of P in the sediments resulted in elevation of P and chlorophyll-a concentration in the pond water. The dissolved P concentration in the pond water increased in the order of non-fish ponds （12μg/L）〈 fishponds without feed supply （24 μg/L）〈 fishponds with feed supply （66 μg/L）. linear correlations between concentrations of total P, Olsen-P, algal avail

关键词： eutrophication freshwater fishery phosphorus fraction water quality

Stabilization of Networked Control Systems Using a Mixed-Mode Based Switched Delay System Method

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IEEE/CAA Journal of Automatica Sinica 2018年第6期5卷 1089-1098页

作者： Qing-kui li Xiaoli li Jiuhe Wang Shengli Du School of Automation Beijing Information Science and Technology UniversityBeijing 100192China Faculty of Information Technology Beijing University of TechnologyBeijing 100124China

The phenomenon of mixed-mode is one of the most important characteristics of switched delay systems. If a networked control system(NCS) with network induced delays and packet dropouts(NIDs & PDs) is recast as a switched delay system, it is imperative to consider the effects of mixed-modes in the stability analysis for an NCS. In this paper, with the help of the interpolatory quadrature formula and the average dwell time method, stabilization of NCSs using a mixed-mode based switched delay system method is investigated based on a novel constructed Lyapunov-Krasovskii functional. With the Finsler's lemma, new exponential stabilizability conditions with less conservativeness are given for the NCS. Finally, an illustrative example is provided to verify the effectiveness of the developed results.

关键词： Interpolatory quadrature formula mixed-mode networked control system (NCS) switched delay system

Future livestock breeding： Precision breeding based on multiomics information and population personalization

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Journal of Integrative Agriculture 2017年第12期16卷 2784-2791页

作者： YANG Ya-lan ZHOU Rong li kui Institute of Animal Science Chinese A cademy of Agricultural Sciences Beijing 100193 P.R. China

With the rapid development of molecular biology and related disciplines, animal breeding has moved from conventional breeding to molecular breeding. Marker-assisted selection and genomic selection have become mainstream practices in molecular breeding of livestock. However, these techniques only use information from genomic variation but not multi-omics information, thus do not fully explain the molecular basis of phenotypic variations in complex traits. In addition, the accuracy of breeding value estimation based on these techniques is occasionally controversial in different populations or varieties. Given the rapid development of high-throughput sequencing techniques and functional genome and dramatic reductions in the overall cost of sequencing, it is possible to clarify the interactions between genes and formation of phenotypes using massive sets of omic-level data from studies of the transcriptome, proteome, epigenome, and metabolome. During livestock breeding, multi-omics information regarding breeding populations and individuals should be taken into account. The interactive regulatory networks governing gene regulation and phenotype formation in diverse livestock population, varieties and species should be analyzed. In addition, a multi-omics regulatory breeding model should be constructed. Precision, population-personalized breeding is expected to become a crucial practice in future livestock breeding. Precision breeding of individuals can be achieved by combining population genomic information at multi-omics levels together with genomic selection and genome editing techniques.

关键词： livestock breeding multi-omics population personalization

Improved carrier transport in Mn:ZnSe quantum dots sensitized La-doped nano-TiO2 thin film

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Chinese Physics B 2020年第4期29卷 351-359页

作者： Shao li Gang li li-Shuang Yang kui-Ying li State Key Laboratory of Metastable Materials Science and Technology College of Materials Science and EngineeringYanshan UniversityQinhuangdao 066004China

Mn:ZnSe/ZnS/L-Cys core-shell quantum dots(QDs)sensitized La-doped nano-TiO2 thin film(QDSTF)was prepared.X-ray photoelectron spectroscopy(XPS),nanosecond transient photovoltaic(TPV),and steady state surface photovoltaic(SPV)technologies were used for probing the photoelectron behaviors in the Mn-doped *** results revealed that the Mn-doped QDSTF had a p-type TPV *** bottom of the conduction band of the QDs as a sensitizer was just 0.86 eV above that of the La-doped nano-TiO2 thin film,while the acceptor level of the doped Mn2+ions was located at about 0.39 eV below and near the bottom of the conduction band of the *** intensity of the SPV response of the Mn-doped QDSTF at a specific wavelength was ~2.1 times higher than that of the undoped *** region of the SPV response of the Mn-doped QDSTF was extended by 191 nm to almost the whole visible region as compared with the undoped QDSTF *** the region of the TPV response of the Mn-doped QDSTF was also obviously wider than that of the undoped *** PV characteristics of the Mn-doped QDSTF may be due to the prolonged lifetime and extended diffusion length of photogenerated free charge carriers injected into the sensitized La-doped nano-TiO2 thin film.

关键词： doping effects ZnSe quantum dots sensitization nano-TiO2 thin film photoelectron spectroscopy

Integrating Inventory Monitoring and Capacity Changes in Dynamic Supply Chains With Bi-Directional Cascading Propagation Effects

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IEEE/CAA Journal of Automatica Sinica 2024年第12期11卷 2515-2518页

作者： En-Zhi Cao Chen Peng Qing-kui li the School of Mechatronic Engineering and Automation Shanghai University IEEE the School of Automation Beijing Information Science and Technology University

Dear Editor,This letter focuses on the integration of inventory monitoring and capacity changes in dynamic supply chains(SCs) with the bullwhip effect(BE) and the ripple effect(RE). First, a new inventory monitoring model with stochastic switched topologies is proposed for SCs, potentially showing merits in incorporating the BE and the RE,and allowing control-theoretic approaches to identify their interrelations. Then, sufficient conditions on the existence of inventory controllers are derived such that the monitoring system is stabilizable with mitigation of the BE in the presence of the RE.

关键词： Monitoring Fluctuations Control theory Switches Topology Raw materials Markov processes

Competitive adsorption and mobility sequence of heavy metals in urban soils of southeastern China

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Journal of Environmental Sciences 2006年第2期18卷 329-333页

作者： ZHANG Ming-kui FANG li-ping HUANG Chang-yong Department of Natural Resource Sciences College of Natural Resource and Environmental Sciences Zhejiang University Hangzhou 310029 China

Heavy metals can be introduced into urban soils at the same time. Therefore, their selective retention and competitive adsorption by the soils become of major importance in determining their availability and movement throughout the soil. In this study, the availability and mobility of six heavy metals in eight urban soils collected from different cities of Zhejiang Province, southeastern China were assessed using distribution coefficients（Kd） and retardation factor（Rf）. The results showed that there were great differences in the Kd and Rfamong the tested soils. The adsorption sequences were Cr〉Pb〉Cu〉Cd〉Zn〉Ni, and the Kd decreased with increasing levels of metal addition. Ni generally has the lowest Rf values followed closely by Cd, and Zn whereas Cr and Pb reached the highest values. The results suggest that Ni and Zn have the highest mobility associated to the lowest adsorption, Cr and Pb present the opposite behavior. Correlation analysis indicates that soil pH, CaCO3 content, and cation exchange capacity （CEC） are key factors controlling the solubility and mobility of the metals in the urban soils.

关键词： competitive adsorption mobility sequence heavy metal urban soil

Reaction mechanism,insensitivity and mechanical property of PTFE-Mg-W composites with magnesium particles surface modification

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Rare Metals 2023年第2期42卷 688-696页

作者： Xin-Bo Zhang Jin-Xu liu liu Wang Shu-kui li School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China

This paper aims at enhancing impact insensitivity of polytetrafluoroethylene(PTFE)-Mg-W without sacrificing bulk of energy released in the reaction and optimizing mechanical properties of PTFE-Mg-W by magnesium surface *** reaction energy results indicate that the reaction energy of PTFE-Mg-W(modified 1 min)in oxygen decreases slightly to 7905 J·g^(-1)compared with that of PTFE-Mg-W(unmodified)which is8533 J·g^(-1).Under impact condition(impact velocity between 16.232 and 17.726 m·s^(-1)),compared with PTFEMg-W(unmodified),the initiation time before ignition of PTFE-Mg-W(modified 1 min)delays 50μs;the absorbed energy needed for ignition of PTFE-Mg-W(modified1 min)increases by 67.9%.This increase in impact insensitivity of PTFE-Mg-W can be contributed to the formation of passivated layers of magnesium particles after modification which effectively weakens the total interface area among reactive components and partly contributes to the loss of released energy of PTFE-Mg-W after magnesium *** quasi-static and dynamic compression results show that PTFE-Mg-W(modified 1 min)possess the highest strength and the best ductility.

关键词： Pyrotechnic compositions Critical phenomena Thermal properties Impact insensitivity

Cs_(2)CuBr_(4)perovskite quantum dots confined in mesoporous CuO framework as a p-n type S-scheme heterojunction for efficient CO_(2)photoconversion

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Chinese Chemical Letters 2024年第11期35卷 582-587页

作者： Zhijie Zhang Xun li Huiling Tang Junhao Wu Chunxia Yao kui li School of Materials Science and Engineering Shanghai Institute of TechnologyShanghai 201418China Institute for Agro-food Standards and Testing Technology Shanghai Academy of Agricultural SciencesShanghai 201403China School of Chemistry and Chemical Engineering Hainan UniversityHaikou 570228China

Heterojunction engineering is recognized as a promising strategy to modulate the photocatalytic properties of ***,lead-free Cs_(2)CuBr_(4)perovskite quantum dots(PQDs)were confined in a mesoporous CuO framework and a p-n type S-scheme heterojunction of Cs_(2)CuBr_(4)/CuO(CCB/CuO)photocatalyst was *** characterizations confirmed the effective confinement of the Cs_(2)CuBr_(4)PQDs in the mesoporous CuO framework,which enabled intimate contact in the interface of CCB/CuO heterojunction,thus facilitating the interfacial charge migration and separation between p-type CuO and n-type Cs_(2)CuBr_(4).Owing to the outstanding charge transport property and CO_(2)adsorption capacity,the developed CCB/CuO heterojunction exhibited remarkably enhanced photocatalytic CO_(2)conversion efficiency with an electron consumption rate(R_(electron))of 281.1μmol g^(-1)h^(-1),which was approximately2.8 times higher than that of pristine Cs_(2)CuBr_(4).These findings provide some insights into the rational engineering design of lead-free perovskite-based heterostructures for efficient photocatalytic CO_(2)conversion.

关键词： Photocatalytic CO_(2)conversion Mesoporous CuO Cs_(2)CuBr_(4) Perovskite quantum dots S-scheme heterojunction

Collaborative filtering recommendation algorithm based on interactive data classification

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The Journal of China Universities of Posts and Telecommunications 2020年第5期27卷 1-12页

作者： Ji Yimu li Ke liu Shangdong liu Qiang Yao Haichang li kui School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing University of Posts and TelocommunicutionsNanjing 210003China Institue of High Performance Computing and Bigdata Nanjing University of Posts and TelecommunicationsNanjing 210003China Nanjing Center of HPC China Nanjing University of Posts and TelocommunicutionsNanjing 210003China Jiangsu HPC and Intelligent Processing Engineer Research Center Nanjing University of Posts and Telocommunicutions Nanjing 210003China

In the matrix factorization(MF)based collaborative filtering recommendation method,the most critical part is to deal with the interaction between the features of users and *** mainstream approach is to use the inner product for MF to describe the user-item ***,as a shallow model,MF has its limitations in describing the relationship between *** addition,when the size of the data is large,the performance of MF is often poor due to data sparsity and *** paper presents a model called PIDC,short for potential interaction data clustering based deep learning ***,it uses classifiers to filter and cluster recommended items to solve the problem of sparse training ***,it combines MF and multi-layer perceptron(MLP)to optimize the prediction effect,and the limitation of inner product on the model expression ability is *** proposed model PIDC is tested on two *** experimental results show that compared with the existing benchmark algorithm,the model improved the recommendation effect.

关键词： personalized recommendation deep learning clustering collaborative filtering