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Site index for Chinese fir plantations varies with climatic and soil factors in southern China

Journal of Forestry Research 2022年第6期33卷 1765-1780页

作者： Xiaoyan Li Aiguo Duan Jianguo Zhang State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Collaborative Innovation Center of Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing 210037People’s Republic of China

Chinese fir[Cunninghamia lanceolata(Lamb.)Hook.]has a large native distribution range in southern China.Here,we tested differences in productivity of Chinese fir plantations in different climatic regions and screened the main environmental factors affecting site productivity in each region.Relationships of a Chinese fir site index with climatic factors and the soil physiochemical properties of five soil layers were examined in a long-term positioning observation trial comprising a total of 45 permanent plots in Fujian(eastern region in the middle subtropics),Guangxi(south subtropics)and Sichuan(central region in the middle subtropics)in southern China.Linear mixed effects models were developed to predict the site index for Chinese fir,which was found to vary significantly among different climatic regions.Available P,total N,bulk density and total K were dominant predictors of site index in three climatic regions.The regional linear mixed models built using these predictors in the three climatic regions fit well(R~2=0.86–0.97).For the whole study area,the available P in the 0–20-cm soil layer and total N in the 80–100-cm soil layer were the most indicative soil factors.MAP was the most important climatic variable influencing the site index.The model evaluation results showed that the fitting performance and prediction accuracy of the global site index model using the climatic region as the dummy variable and random parameters and the most important soil factors of the three climatic regions as predictors was higher than that of global site index model using the climatic variable and the most indicative soil variables of the whole study area.Our results will help with further evaluation of site quality of Chinese fir plantations and the selection of its appropriate sites in southern China as the climatic changes.

关键词： Site productivity Site index Climate Soil Chinese fir

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Novel dynamic evidential Petri net for system reliability analysis

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Journal of Systems Engineering and Electronics 2017年第5期28卷 1019-1027页

作者： Wensheng Peng Jianguo Zhang Jinyang zhang School of Reliability and Systems Engineering Beihang University China Aero-Polytechnology Establishment Aviation Industry Corporation of China Science and Technology on Reliability and Environment Engineering Laboratory Beihang University

This paper proposes a novel dynamic Petri net (PN) model based on Dempster-Shafer (D-S) evidence theory, and this improved evidential Petri net (EPN) model is used in knowledge inference and reliability analysis of complex mechanical systems. The EPN could take epistemic uncertainty such as interval information, subjective information into account by applying D-S evidence quantification theory. A dynamic representation model is also proposed based on the dynamic operation rules of the EPN model, and an improved artificial bee colony (ABC) algorithm is employed to proceed optimization calculation during the complex systems' learning process. The improved ABC algorithm and D-S evidence theory overcome the disadvantage of extremely subjective in traditional knowledge inference efficiently and thus could improve the accuracy of the EPN learning model. Through a simple numerical case and a satellite driving system analysis, this paper proves the superiority of the EPN and the dynamic knowledge representation method in reliability analysis of complex systems.

关键词： evidence theory Petri net knowledge representation improved ABC algorithm imprecise information reliability

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A new structural reliability analysis method in presence of mixed uncertainty variables

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Chinese Journal of Aeronautics 2020年第6期33卷 1673-1682页

作者： Lingfei YOU Jianguo Zhang Xiaosong DU Jie WU School of Reliability and Systems Engineering Beihang University.Beijing 100083China Science and Technology on Reliability and Environmental Engineering Laboratory Beihang UniversityBeijing 100083China

For structures with both random and fuzzy uncertainty,this paper presents a novel method for determining the membership function in fuzzy reliability with the Automatic Updating Extreme Response Surface(AUERS)method.In the proposed method,fuzzy variables are initially converted into a value domain under the given cut level and the extreme point in the domain where the reliability reaches its extreme value is considered.Second,the Particle Swarm Optimization(PSO)algorithm is used to determine the extreme point according to the extreme responses for different sets of random sample inputs.A kriging response surface is subsequently constructed between the random variables and the corresponding extreme points.An automatic updating strategy is then introduced based on the Relative Mean Square Predicted Error(RMSPE)before performing every iteration of reliability analysis.By adding new sample points,the approximate quality of the kriging response surface is improved.Finally,reliability analysis is used to determine the reliability bound under the given cut level.The proposed method assures the accuracy and computation efficiency of the mixed uncertainty reliability analysis results while it prevents the solution from becoming trapped in a local optimum,which occurs in classical optimization methods.Two example analyses are used to demonstrate the validity and advantages of the proposed method.

关键词： Automatic updating strat-egy Extreme response surface Membership function Mixed uncertainty Particle swarm optimization Structure reliability

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Atmospheric fate of typical liquid crystal monomers in the tropospheric gas,liquid,and granular phases

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Journal of Environmental Sciences 2024年第2期136卷 348-360页

作者： Yanru Huo Zexiu An Mingxue Li Jinchan Jiang Yuxin Zhou Ju Xie Jianguo Zhang Maoxia He Environment Research Institute Shandong UniversityQingdao 266237China College of Plant Protection Hebei Agricultural UniversityBaoding 071000China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Jinan Environmental Research Academy Jinan 250000China

Mineral aerosol particles significantly impact environmental risk prediction of liquid crystal monomers(LCMs).In this work,we investigated the reaction mechanisms and kinetics of three typical LCMs(4-cyano-3,5-difluorophenyl 4-ethylbenzoate(CEB-2F),4-cyano-3-fluorophenyl 4-ethylbenzoate(CEB-F),and 4-cyanophenyl 4-ethylbenzoate(CEB))with ozone(O_(3))in the atmospheric gas,liquid,and particle phases employing density functional theory(DFT).Here,O_(3)is prone to add to the benzene ring without F atom(s)in the selected LCMs.The ozonolysis products are aldehydes,carboxylic acids,epoxides,and unsaturated hydrocarbons containing aromatic rings.Those products undergo secondary ozonolysis to generate small molecular compounds such as glyoxal,which is beneficial for generating secondary organic aerosol(SOA).Titanium dioxide(TiO_(2)),an essential component of mineral aerosol particles,has good adsorption properties for LCMs;however,it slightly reduces the reactivity with O_(3).At 298 K,the reaction rate constant of the selected LCMs reacting with O_(3)in the gas and atmospheric liquid phases is(2.74–5.53)×10^(-24)cm^(3)/(mol·sec)and 5.58×10^(-3)–39.1 L/(mol·sec),while CEB-2F reacting with O_(3)on(TiO_(2))_(6)cluster is 1.84×10^(-24)cm^(3)/(mol·sec).The existence of TiO_(2)clusters increases the persistence and long-distance transportability of LCMs,which enlarges the contaminated area of LCMs.

关键词： Liquid crystal monomers(LCMs) Ozonolysis TiO_(2)clusters Adsorption Toxicity assessment

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Strata movement and stress evolution when mining two overlapping panels affected by hard stratum

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International Journal of Mining Science and Technology 2019年第5期29卷 691-699页

作者： Jianguo Zhang Wei Yang Baiquan Lin Jinjing zhang Man Wang State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization China Pingmei Shenma GroupPingdingshan 467000China Key Laboratory of Gas and Fire Control for Coal Mines(China University of Mining and Technology) Ministry of EducationXuzhou 221116China China Pingmei Shenma Group Pingdingshan 467000China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China

Mining causes stress redistribution and stratum movement.In this paper,a numerical model was built according to the geological conditions in the 12th coal mine in Pingdingshan city to study the strata movement and the evolution of stress when mining two overlapping longwall panels,named panels#14 and#15.The strata close to the mined panel move directly towards the gob,while the strata that are farther away swing back and forth during the mining process.The directed movement and swinging can break the transverse boreholes for gas extraction;a surface borehole should not be within the range of directional movement.The stress evolution suggested that the mining of the lower panel#15 after the upper panel#14 would further increase the de-stressed range,while the stress concentration around the mined panel would be increased.Hard strata usually carry a greater stress than adjacent rocks and soft coal seams.The stress in a hard stratum increases greatly,and the stress decreases greatly in the coal seams below the hard stratum.This study supplies a reference for similar coal mines and is useful for determining the de-stressed range and transverse borehole arrangement for gas extraction.

关键词： Stratum movement Mining Longwall panel Hard stratum

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PSI-driven cyclic electron fl ow partially alleviates the peroxidation of red alga Gelidium amansii(Gelidiaceae)caused by temporary high temperature

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Journal of Oceanology and Limnology 2022年第1期40卷 206-215页

作者： Yongfu LI jianguo LIU Litao zhang CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Marine Biology and Biotechnology Laboratory Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

PSI-driven cyclic electron fl ow(CEF-I)helps higher plants avoid severe heat damage.Gelidium amansii,a red seaweed used in the production of agar,inhabits subtidal rocks but can be found in the intertidal zone.The biological role of CEF-I is still unclear in this organism.Wild G.amansii was exposed to 30℃heat stress for 12 h with continuous lighting.The results showed that treatment at 30℃gradually decreased maximal PSII photochemical effi ciency(F_(v)/F_(m)),linear electron transfer rate,and activity of photosynthetic reaction center.Both the maximal photochemical effi ciency under light(F_(v)'/F_(m)')and maximum quantum yield of light-adapted PSII(Φ_(PSII))were maintained at a relatively stable level during the initial 6 h and then signifi cantly decreased at 12 h.The up-regulated CEF-I helps to enhance proton gradient transfer across thylakoid membrane to protect oxygen-evolving complex against heat damage.Following the addition of a CEF-I inhibitor to plants,the F_(v)/F m greatly decreased,suggesting that the CEF-I alleviates degree of photoinhibition caused by strong light.The results of measurement of antioxidant enzymes,including superoxide dismutase(SOD),ascorbate peroxidase(APX)and catalase(CAT),and the contents of H_(2)O_(2)and malonaldehyde(MDA)provided additional evidence that CEF-I plays a protective role to a certain extent for G.amansii to manage stress at 30℃.Therefore,it can be concluded that CEF-I enables G.amansii to survive in intertidal zones by protecting it from the heat damage caused by high temperature stress.

关键词： cyclic electron fl ow Gelidium amansii heat stress chlorophyll fl uorescence quantum yield natural distribution

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Transcriptome-wide effect of Salix SmSPR1 in etiolated seedling of Arabidopsis

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Journal of Forestry Research 2021年第3期32卷 975-985页

作者： Xiaoxia Liu Jianguo Zhang Li Xue Guodong Rao State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Collaborative Innovation Center of Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing 210037People’s Republic of China Key Laboratory of Tree Breeding and Cultivation State Forestry AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China

Microtubules and their regulatory proteins are involved in the regulation of plant cell morphology.SPIRAL1(SPR1),a plant-specific microtubule-binding protein,is critical in regulating the anisotropic growth of plant cells.Our previous study showed that overexpressed S alix SmS PR1 genes in Arabidopsis thaliana caused right-handed spiral elongation in etiolated seedlings,but there were no morphological differences between wild-type and transgenic seedlings under varied light conditions.We then studied the transcriptional regulation patterns in transgenic plants engineered with the S mSPR1 gene.Transcriptomic results showed that a large number of differentially expressed genes were involved in plant light signal reception,chlorophyll synthesis and photosystem structure.Eleven gene families with 42 photosynthesis-related genes and 6 light-responsive genes were involved in regulation of cell morphology.Our results showed that these genes in the SmSPR1-ox line were particularly down-regulated under dark conditions.In addition,33 TFs showed differences between S mSPR1-ox and wild-type lines.Taken together,the transcriptome analysis provides new insight into investigating the molecular mechanisms of light-induced cell morphological changes mediated by the microtubule binding protein SPR1.

关键词： Arabidopsis thaliana Cell anisotropism SmSPR1 Transcription factor Transcriptome analysis

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Structural insights into the Omicron spike trimer:tackling the challenges of continuously evolving SARS-CoV-2 variants

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Signal Transduction and Targeted Therapy 2022年第10期7卷 3625-3627页

作者： Junxian Ou jianguo Wu Qiwei zhang Guangdong Provincial Key Laboratory of Virology Institute of Medical MicrobiologyJinan University510632 GuangzhouChina

The recent studies published in Science and Cell Research investigated the structures and biochemical mechanism of the SARS-CoV-2 Omicron BA.1 and BA.2 spike trimer with ACE2 as well as an effective antibody JMB2002 against BA.1 and BA.2 spike,which provide new insights for the global development of broadspectrum anti-SARS-CoV-2 antibodies and vaccines.

关键词： ACE2 insight continuously

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Experimental study on conversion path of sulfur in coal slime preheating combustion

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Waste Disposal and Sustainable Energy 2022年第1期4卷 63-68页

作者： Jiahang zhang jianguo Zhu Qinggang Lv Yi zhang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

In this study,coal slime was mainly utilized to conduct experiments on a 30 kW preheating combustion test rig to analyze the conversion pathway of sulfur during the experiment,aiming at reducing slime pollution,controlling sulfur emission reasonably,and providing theoretical support for the preheating combustion technology.The results showed that after the coal slime was preheated,a large number of elements were released.The maximum release rates for H and S were 94.0%and 73.3%,respectively.The released S was converted into the sulfur-containing gases like H_(2)S,COS,CS_(2),and the rest existed in the solid in the five forms of mercaptan,thiophene,sulfoxide,sulfone,and sulfate.Besides,during the combustion process,the gas was oxidized continuously and finally converted into SO2,leaving only the sulfate in the fly ash.In the preheating combustion process,26.7%of the S was released from the coal,73.3%of the S was retained in the semi-coke,and the final SO2 emission concentration of combustion was 959 ppm.

关键词： Preheating combustion Sulfur Conversation path Coal slime Experimental study

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Technical methods of national security supervision:Grain storage security as an example

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Journal of Safety Science and Resilience 2023年第1期4卷 61-74页

作者： Yudie Jianyao Qi zhang Liang Ge jianguo Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Institute of Public Safety Research Tsinghua UniversityBeijing 100084China Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China National Food and Strategic Reserves Administration Beijing 100084China

Grain security guarantees national security.China has many widely distributed grain depots to supervise grain storage security.However,this has led to a lack of regulatory capacity and manpower.Amid the development of reserve-level information technology,big data supervision of grain storage security should be improved.This study proposes big data research architecture and an analysis model for grain storage security;as an example,it illustrates the supervision of the grain loss problem in storage security.The statistical analysis model and the prediction and clustering-based model for grain loss supervision were used to mine abnormal data.A combination of feature extraction and feature selection reduction methods were chosen for dimensionality.A comparative analysis showed that the nonlinear prediction model performed better on the grain loss data set,with R2 of 87.21%,87.83%,91.97%,and 89.40%for Gradient Boosting Regressor(GBR),Random Forest,Decision Tree,XGBoost regression on test sets,respectively.Nineteen abnormal data were filtered out by GBR combined with residuals as an example.The deep learning model had the best performance on the mean absolute error,with an R2 of 85.14%on the test set and only one abnormal data identified.This is contrary to the original intention of finding as many anomalies as possible for supervisory purposes.Five classes were generated using principal component analysis dimensionality reduction combined with Density-Based Spatial Clustering of Applications with Noise(DBSCAN)clustering,with 11 anomalous data points screened by adding the amount of normalized grain loss.Based on the existing grain information system,this paper provides a supervision model for grain storage that can help mine abnormal data.Unlike the current post-event supervision model,this study proposes a pre-event supervision model.This study provides a framework of ideas for subsequent scholarly research;the addition of big data technology will help improve efficient supervisory capacity in the field of grain sup

关键词： Grain storage security Supervision model Abnormal data mining

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