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Land use effects on the dynamics of soil C,N and microbes in the water-wind erosion crisscross region of the northern Loess Plateau,China

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Pedosphere 2024年第1期34卷 181-190页

作者： Yi WAng Chunyue li Shunjin HU State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China State Key Laboratory of Soil Erosion and Dryland farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China Department of Entomology&Plant Pathology North Carolina State UniversityRaleigh 27695USA

The water-wind erosion crisscross region of the northern Loess Plateau in China is under constant pressure from severe erosion due to its windy and dry climate and intensive human activities. Identifying sustainable land use patterns is key to maintaining ecosystem sustainability in the area. Our aim was to appraise the impacts of different land use regimes on the dynamics of soil total organic C(TOC), total N(TN), and microbes in a typical watershed in the northern Loess Plateau to identify suitable land use types that can maintain soil fertility and sustainability. A field experiment was performed in liudaogou watershed in Shenmu City, Shaanxi Province, China, where the dynamics of soil TOC and TN, microbial biomass C and N, microbial respiration, and net N mineralization in six typical land use types, dam land, rainfed slope land, deciduous broadleaf forest, evergreen coniferous forest, shrubland, and grassland,were measured in three different growing seasons. Land use type and season significantly affected TOC, TN, and the dynamics of microbial biomass and activity. As the most anthropogenically disturbed land use pattern, dam land was an optimal land use pattern for TOC sequestration due to its higher TOC and TN, but lower microbial activity. Soil TOC, TN, and microbial properties demonstrated a decreasing trend after natural grassland was converted to shrubland,forest, and rainfed slope land. Shrubland with exotic N-fixing Korshinsk peashrub(Caragana korshinskii Kom.) can maintain TOC, TN, and microbial properties similar to those in grassland. Soil TOC, NH_(4+)^(-)N, TN, moisture, and extractable C were the principal indexes for soil microbial biomass and activity and explained 88.90% of the total variance. Thus, grassland was the optimal land use pattern in the water-wind erosion crisscross region of the northern Loess Plateau to maintain ecosystem stability and sustainability.

关键词： grassland microbial activity microbial biomass total organic C total N watershed

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Laboratory and numerical modelling of irrigation infiltration and nitrogen leaching in homogeneous soils

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Pedosphere 2024年第1期34卷 146-158页

作者： Lei WU Ruizhi li Yan WAng Zongjun GUO Jiaheng li Hang YAng Xiaoyi MA Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas Ministry of EducationNorthwest A&F UniversityYangling 712100China Blackland Research and Extension Center Texas A&M AgriLife ResearchTexas A&M UniversityTemple TX 76502USA State Key Laboratory of Soil Erosion and Dryland farming on the Loess Plateau Northwest A&F UniversityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China

Nitrogen (N) plays a key role in crop growth and production;however,data are lacking especially regarding the interaction of biochar,grass cover,and irrigation on N leaching in saturated soil *** soil columns with 20-cm diameter and 60-cm height were designed to characterize the effects of different grass cover and biochar combinations,i.e.,bare soil+0%biochar (control,CK),perennial ryegrass+0%biochar (C1),festuca arundinacea+0%biochar (C2),perennial ryegrass+1%biochar (C3),perennial ryegrass+2%biochar (C4),perennial ryegrass+3%biochar (C5),***+1%biochar (C6),***+2% biochar (C7),and ***+3%biochar (C8),on periodic irrigation infiltration and N leaching in homogeneous loess soils from July to December *** in CK were 10.2%–35.3%higher than those in C1 and *** perennial ryegrass and *** decreased the volumes of leachates and delayed the leaching process in the 1%,2%,and 3%biochar treatments,and the vertical leaching rate decreased with biochar *** N leaching losses were concentrated in the first few leaching tests,and both total N (TN) and nitrate (NO_(3)^(-))-N concentrations in CK and C1–C8 decreased with increasing leaching test *** addition (1%,2%,and 3%) could further reduce the leaching risk of NO_(3)^(-)-N and the NO_(3)^(-)-N loss decreased with biochar ***,compared to 1%biochar,2% biochar promoted the leaching of TN under both grass cover *** N leaching losses in CK,C1,C2,C3,C4,C6,and C7 were primarily in the form of NO_(3)^(-)-*** these treatments,CK,C1,and C2had the highest cumulative leaching fractions NO_(3)^(-)-N (>90%),followed by those in C3,C4,C6,and C7 (>80%).The cumulative leaching fraction of NO_(3)^(-)-N decreased with increasing leaching test times and biochar addition,and 3%biochar addition (i.e.,C5 and C8) reduced it to approximately 50%.The one-dimensional advective-dispersive-reactive transport equation can be used as an effective nume

关键词： leaching loss nitrate nitrogen biochar grass cover analytical modelling

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Stability analysis of intermittently jointed rock slopes based on the stepped failure mode

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Journal of Mountain Science 2024年第3期21卷 1019-1035页

作者： li Dejian fU Junwen li Hekai CHEng Xiao ZHAO lianheng ZHAng Yingbin PEng Xinyan School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Institute for Disaster Management and Reconstruction College of Architecture&EnvironmentSichuan UniversityChengdu 610065China School of Civil Engineering Key Laboratory of Heavy-Haul Railway Engineering StructureMinistry of EducationHunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering StructureCentral South UniversityChangsha 410075China

In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock *** for intermittently bedding jointed rock slopes,the correlation and difference in strength parameters between joints and rock bridges,along with the various failure modes and intermittency of rock bridges,contribute to the complexity of stepped failure modes and the unpredictability of failure *** on the upper-bound limit analysis method and multi-sliders step-path failure mode,considering the shear and tensile failure of rock bridges and the weakened relationship between the strength parameters of rock bridges and jointed surfaces,by introducing the modified M-C failure criterion and the formula for calculating the energy consumption of tensile failure of rock bridges,two failure mechanisms are constructed to obtain the safety factor(f_(s))of intermittently jointed rock *** sequential quadratic programming method is used to obtain the optimal upper-bound solution for f_(s).The influence of multiple key parameters(slope height H,horizontal distance L,Slope angleβ,shear strength parameters of the rock bridgeφr and cr,Dimensionless parameter u,weakening coefficients of the internal friction angle and cohesion between the rock bridges and joint surfaces Kφand Kc)on the stability analysis of intermittently jointed rock slopes under the shear failure mode of rock bridges as well as under the tensile failure mode is also *** reliability of the failure mechanisms is verified by comparative analysis with theoretical results,numerical results,and landslide cases,and the variation rules of f_(s)with each key parameter are *** results show that f_(s) varies linearly withφr and cr of the rock bridge and with K_(φ)and K_(c),whereas f_(s)changes nonlinearly with H and *** particular,with the increase in Kφand Kc,fs increases by approximately 52.

关键词： Jointed rock slopes Stepped sliding failure Weakening characteristics Modified M‒C failure criterion

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Near-infrared non-fused electron acceptors for efficient organic photovoltaics

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Chinese Chemical Letters 2024年第4期35卷 436-441页

作者： Wenxiang Ma Xinyu He Tianyi Chen De-li Ma Hongzheng Chen Chang-Zhi li State Key Laboratory of Silicon and Advanced Semiconductor Materials Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Developing narrow-bandgap organic semiconductors is important to facilitate the advancement of organic photovoltaics(OPVs). Herein, two near-infrared non-fused ring acceptors(NIR NfRAs), PTBfTT-f and PTBfTT-Cl have been developed with A-π_A-π_D-D-π_D-π_A-A non-fused structures. It is revealed that the introduction of electron deficient π-bridge(π_A) and multiple intramolecular noncovalent interactions effectively retained the structural planarity and intramolecular charge transfer of NfRAs, extending strong NIR photon absorption up to 950 nm. further, the chlorinated acceptor, with the enlarged π-surface compared to the fluorinated counterpart, promoted not only molecular stacking in solid, but also the desirable photochemical stability in ambient, which are helpful to thereby improve the exciton and charge dynamics for the corresponding OPVs. Overall, this work provides valuable insights into the design of NIR organic semiconductors.

关键词： Organic photovoltaic Near-infrared Non-fused electron acceptor Noncovalent interaction Stability

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Thermodynamic Performance Analysis of E/f/H-Class Gas Turbine Combined Cycle with Exhaust Gas Recirculation and Inlet/Variable Guide Vane Adjustment under Part-Load Conditions

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Journal of Thermal Science 2024年第1期33卷 348-367页

作者： li Keying CHI Jinling WAng Bo ZHAng Shijie Key Lab of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Mechanical Electronic&Information Engineering China University of Mining&Technology-BeijingBeijing 100083China

Exhaust gas recirculation control(EGRC),an inlet air heating technology,can be utilized in combination with inlet/variable guide vane control(IGV/VGVC) and fuel flow control(ffC) to regulate the load,thereby effectively improving the part-load(i.e.,off-design) performance of the gas turbine combined cycle(GTCC).In this study,the E-,f-,and H-Class EGR-GTCC design and off-design system models were established and validated to perform a comparative analysis of the part-load performance under the EGR-IGV-ffC and conventional IGV-ffC strategies in the E/f/H-Class *** show that EGR-IGV-ffC has considerable potential for the part-load performance enhancement and can show a higher combined cycle efficiency than IGV-ffC in the E-,f-,and H-Class ***,the part-load performance improvement in the corresponding GTCC was weakened for the higher class of the gas turbine because of the narrower load range of EGR action and the deterioration of the gas turbine ***,EGR-IGV-ffC was inferior to IGV-ffC in improving the performance at loads below 50% for the H-Class *** results obtained in this paper could help guide the application of EGR-IGV-ffC to enhance the part-load performance of various classes of GTCC systems.

关键词： E/f/H-Class gas turbine combined cycle performance improvement part-load conditions exhaust gas recirculation inlet/variable guide vane

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Recursive filtering for Stochastic Systems With filter-and-forward Successive Relays

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1202-1212页

作者： Hailong Tan Bo Shen Qi li Hongjian liu School of Mathematics-Physics and finance Anhui Polytechnic UniversityWuhu 241000China Anhui future Technology Research Institute Anhui Polytechnic UniversityWuhu 241000China College of Information Science and Technology Donghua UniversityShanghai 201620China Engineering Research Center of Digitalized Textile and fashion Technology Ministry of EducationShanghai 201620China School of Information Science and Engineering Hangzhou Normal UniversityHangzhou 311121China

In this paper,the recursive filtering problem is considered for stochastic systems over filter-and-forward successive relay(ffSR)*** ffSR is located between the sensor and the remote filter to forward the *** the successive relay,two cooperative relay nodes are adopted to forward the signals alternatively,thereby existing switching characteristics and inter-relay interferences(IRI).Since the filter-and-forward scheme is employed,the signal received by the relay is retransmitted after it passes through a linear *** objective of the paper is to concurrently design optimal recursive filters for ffSR and stochastic systems against switching characteristics and IRI of ***,a uniform measurement model is proposed by analyzing the transmission mechanism of ***,novel filter structures with switching parameters are constructed for both ffSR and stochastic *** the help of the inductive method,filtering error covariances are presented in the form of coupled difference ***,the desired filter gain matrices are further obtained by minimizing the trace of filtering error ***,the stability performance of the filtering algorithm is analyzed where the uniform bound is guaranteed on the filtering error ***,the effectiveness of the proposed filtering method over ffSR is verified by a three-order resistance-inductance-capacitance circuit system.

关键词： filtering successive stochastic

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finite-time composite learning control for nonlinear teleoperation systems under networked time-varying delays

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Science China(Information Sciences) 2024年第6期67卷 279-296页

作者： Yana YAng Huixin JIAng Changchun HUA Junpeng li Institute of Electrical Engineering Yanshan University

The robust finite-time synchronization control problem is investigated for master-slave networked nonlinear telerobotics systems(NNTSs) in this article. Although there have been some research achievements on finite-time control for the NNTSs, these studies are based on the strong assumptions of communication time delays or can only achieve finite-time bounded convergence even when the external forces are *** and in view of the importance of these issues, a novel robust composite learning adaptive control scheme rendering the finite-time master-slave synchronization is proposed in this paper. In particular, the influence of time delays on finite-time convergence of the system is analyzed by employing the multi-dimension finite-time small-gain framework. Meanwhile, in order to achieve accurate and fast estimation of uncertain parameters of the system, both the online historical and the instantaneous data of the estimation data are explored to derive the new parameter adaptive law under a more realizable interval-excitation(IE) ***, the convergence of the position/force synchronization errors and the adaptive parameter estimation errors is obtained in finite time, and enhanced robustness of the closed-loop system will also be ***, the superior performance of the proposed control algorithms is validated by numerical simulations and hardware experiments.

关键词： networked teleoperation systems finite-time control exact parameter estimation small-gain theorem unknown communication delays

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Resilient sliding mode control for 2D CPSs under denial-of-service attacks

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Science China(Information Sciences) 2024年第6期67卷 262-278页

作者： lingling li Rongni YAng Zhiguang f.ng ligang WU College of Intelligent Systems Science and Engineering Harbin Engineering University School of Control Science and Engineering Shandong University School of Astronautics Harbin Institute of Technology

This study addresses the resilient sliding mode control(SMC) problem for two-dimensional cyber-physical systems(2D CPSs) characterized by the Roesser model under denial-of-service attack(DoSA), which can interfere with signal transmission over the communication network. first, the DoS-A model is established by introducing constraints on the Do S frequency and duration. Then, based on active or silent attack situations, the considered system is described as a switched mode. furthermore, together with Lyapunov theory, the average dwell time technique is employed to deduce sufficient criteria that assure the existence of the desired sliding mode controller. finally, verification examples are provided to show the validity of the established SMC scheme.

关键词： two-dimensional systems cyber-physical systems denial-of-service attack resilient sliding mode control

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Modulation mechanism of electron energy dissipation on superlubricity based on fluorinated 2D ZIfs

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Nano Research 2024年第4期17卷 3198-3209页

作者： Yuxin li Lei liu Kunpeng Wang Yuhong liu State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China School of Mechatronic Engineering Shanghai UniversityShanghai 200444China

Electron energy dissipation is an important energy dissipation pathway that cannot be ignored in friction ***-dimensional zeolite imidazole frameworks(2D ZIfs)and fluorine doping strategies give 2D Zn-ZIf and 2D Co-ZIf unique electrical properties,making them ideal materials for studying electron energy dissipation *** this paper,based on the superlubricity modulation of 2D fluoridated ZIfs,the optimal tribological properties are obtained on the 2D f-Co-ZIf surface,with the friction coefficient as low as *** experiments,density functional theory(DfT)simulation,and fluorescence detection are used to explain the mechanism of fluorine doping regulation of tribological properties from the two stages,namely energy transfer and energy ***,the energy will transfer into the friction system through the generation of electron–hole pairs under an external excitation,and release by radiation and non-radiation energy dissipation *** reduces energy transfer by altering the electronic properties and band structures of ZIfs,and slows down the charge transfer by enhancing the shielding efficiency,thus slowing the non-radiative energy dissipation rate during the energy release *** insights not only help us better understand the role of fluorine doping in improving tribological properties,but also provide a new way to further explore the electron energy dissipation pathway during friction.

关键词： superlubricity electron energy dissipation modulation two-dimensional zeolite imidazole frameworks(2D ZIfs) fluorination

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Bortezomib depended on PRDM1 and TP53 to exert therapeutic effect in activated B-cell-like diffuse large B-cell lymphoma

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Genes & Diseases 2024年第2期11卷 550-553页

作者： Jing Tang Yue li Jiazhu Wu Haorui Shen Hua Yin Jinhua liang li Wang Jianyong li Yi Xia Wei Xu Department of Hematology The First Affiliated Hospital of Nanjing Medical UniversityJiangsu Province HospitalNanjingJiangsu 210029China Key Laboratory of Hematology of Nanjing Medical University NanjingJiangsu 210029China Collaborative Innovation Center for Cancer Personalized Medicine NanjingJiangsu 210029China

PR/SET domain 1(PRDM1)gene is located on chromosome 6q21,encoding the B lymphocyte-induced maturation protein 1(BliMP1).1 It is reported that loss of PRDM1 function is exacerbated in activated B-cell-like(ABC)-diffuse large B cell lymphoma(DLBCL)and associated with inferior ***,it remains unclear what leads to PRDM1 inactivation and the drug resistance mechanism caused by abnormal inactivation of *** investigated the contribution of PRDM1 gene as a prognosis and potential therapeutic target for ABC-DLBCL patients and further clarified the possible mechanism of PRDM1 abnormal *** first proposed that TP53 could regulate PRDM1 by histone ubiquitination modification at the post-transcriptional level.

关键词： PRDM1 TP53 therapeutic

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