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Bio-Mobilization of Potassium from Clay Minerals: Ⅱ. By Ectomycorrhizal Fungi

Pedosphere 2000年第4期10卷 347-354页

作者： yuan ling, wang zhihui, fang dehua, shun hong and huang jianguo (College of Resources and Environment, Southwest Agricultural University, Chongqing 400716 China)

Ectomycorrhizal fungi, including Cenococcum geophilum SIV (Cg SIV), and Pisolithus tinctorius 2144 (Pt 2144), 441 (Pt 441) and XC1 (Pt XC1), were cultured in Pachlewski liquid medium with H2KPO4,KCl- saturated vermiculite and mica as K sources, respectively, to investigate the mechanism of K absorption and mobilization by the fungi. Fungal growth rate, K absorption and mobilization varied significantly among the fungal species. Faster growth and greater K accumulation in Pt XC1 than Pt 2 144, Pt 441 and Cg siv were observed. Ectomycorrhizal fungi depressed HCl-soluble K in minerals after successive extractions by water and NH4OAc. Ratio of the total amount of K, including water-, NH4OAc- and HCI-soluble K, lost from substrates to the K accumulated in fungal colonies was less than 60%. These reveal that the ectomycorrhizal fungi could utilize K in interlayer and structural pools, which are usually unavailable for plants in short period. Large differences in the depletion of K in interlayer and structural pools by fungi were observed at fungal harvest. Taking into account the nutrient absorption by ectomycorrhizal fungi in symbionts and the direct contact between hyphae and soils, the fungi species colonized on the root surfaces seemed to be related to the effectiveness of mycorrhizas to utilize K in soils. Ectomycorrhizal fungi differed in the efflux of protons and oxalate. Pt XC1 was observed to have greatest ability to effuse protons and oxalate among the fungi adopted in the experiment. Furthermore, the higher the concentrations of protons and oxalate in the liquid culture solutions, the larger the depletion of K in interlayer and structural pools in minerals by fungi. Protons could replace interlayer K and chelation of oxalate with Fe and Al in crystal lattice could cause weathering of clay minerals. So, protons and oxalate produced by ectomycorrhizal fungi might play an important role in K mobilization in these two pools.

关键词： ectomycorrhizal fungi K proton and oxalate

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Bio-Mobilization of Potassium from Clay Minerals: I. By Ectomycorrhizas

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Pedosphere 2000年第4期10卷 339-346页

作者： yuan ling, fang dehua, wang zhihui, shun hong and huang jianguo (College of Resources and Environment, Southwest Agricultural University, Chongqing 400716 China) 西南农业大学重庆 400716

A pot experiment was carried out to investigate effect of ectomycorrhizal fungi on eucalyptus growth and K bio-mobilization from soils and clay minerals. In the experiment, sands mixed with soil, KCI-saturated vermiculate and mica, respectively, were used to nurse eucalyptus seedlings which were nonectomycorrhized or ectomycorrhized by an ectomycorrhizal fungus Pisolithus tinctorius strain XCI (Pt XC1) isolated from a forest soil from Xichang, Sichuan Province, China, and a worldwide well-known ectomycorrhizal fungus Pisolithus tinctorius strain 2144 (Pt 2144) obtained in Australia. More depletion of HCl-soluble K by mycorrhizas from the soil and minerals than nonmycorrhizas suggested that mycorrhizas had a great ability to mobilize K present in the interlayer and feldspar. Mycorrhizal seedlings depressed greatly K digested with HF-HCIO4 from substrates after consecutive extractions of soils and minerals by water, ammonium cetate and boiling HCl, while nonmycorrhizal seedlings reduced it little if any, showing that the mycorrhizal seedlings could mobilize and then utilize the structural K in mineral lattice. Ectomycorrhizal fungi played a very important role not only in promoting the growth of eucalyptus seedlings but also in mobilizing K in soils and minerals. The infection of Pt XC1 led to a better growth of eucalyptus seedlings and more K accumulation in the seedlings than that of Pt 2144. The large differences in K accumulation by the seedlings might be due to different abilities of the two ectomycorrhizal fungi to mobilize K in interlayer and lattice pools in the clay minerals.

关键词： clay minerals ectomycorrhizas eucalyptus K mobilization

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Tea-Grown Soils and Tea Quality in Sichuan and Chongqing, China

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Pedosphere 2000年第1期10卷 45-52页

作者： yuan ling, wang SHOUSHENG, wang zhihui and huang jianguo (College of Resources and Environment, Southwest Agricultural University, Chongqing 400716 (China)) 西南农业大学重庆 400716

Made teas and typical tea-grown soils in Sichuan and Chongqing were collected to investigate soil nutrients, related soil properties and tea quality. The tea-grown soils in Sichuan and Chongqing are distributed mainly in mountainous areas. The high annual precipitation (over 1100 mm), precipitous soil slopes, low cohesion among soil particles and high soil porosity suggested that intensive erosion and leaching might occur in these soils. Moreover, they were very acidic and poor in mineral nutrients such as N, P, K, Ca and Mg except S. The average content of total S was 20.40 g kg-1, much higher than that of organic matter in these soils, revealing that S in the tea-grown soils existed mainly in inorganic forms and very little in organic forms. Water-extractable S accounted for only a small amount of total S, which showed that most parts of sulfur in these soils were insoluble in W8ter. K and S varied greatly in made teas. The concentrations of N and P, however, varied little in these teas even though they differentiated significantly in the tea-grown soils. The high concentration of nitrogen in made teas could result in the high free amino acids and low polyphenol of teas. Significantly positive correlation was established between potassium and polyphenol in made teas. Teas with high ratio of phenol to free amino acids were usually good in taste and appearance.

关键词： mineral nutrients soil tea

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Morphology-dependent interfacial interactions of Fe2O3 with Ag nanoparticles for determining the catalytic reduction of p-nitrophenol

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Journal of Environmental Sciences 2020年第6期32卷 1-10页

作者： Ningning wang Shuai Zeng hong yuan Jin huang Key Laboratory of Pesticide and Chemical Biology of Ministry of Education College of ChemistryCentral China Normal UniversityWuhan 430079China Chongqing Key Laboratory of Soft-Matter Material Chemistry and Function Manufacturing School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China

In this work,we fabricated three kinds of Ag/Fe2O3 model catalysts with different morphologies to study the interfacial interactions between Ag and Fe2O3,and how they affected the catalytic activity in hydrogenation of p-nitrophenol was *** hydrothermal method was used to synthesize the metal oxide supported silver catalyst,with various morphologies including nanoplates(NPs),nanospheres(NSs),and nanocubes(NCs).The crystal structure,morphology and surface elements of the composite were investigated by various measurements,such as X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).The catalytic activity was also evaluated by the reduction of p-nitrophenol to *** was found that the activities of the above catalysts varied with the morphology of the *** them,Ag/Fe2O3 NPs promoted the highest performance,Ag/Fe2O3 NSs were slightly inferior,and Ag/Fe2O3 NCs were the *** last,we ascribed the remarkable activity of Ag/Fe2O3 NPs to the strong metal-support interactions between Ag and Fe2O3.

关键词： Ag/Fe2O3 Interfacial interaction Catalytic activity p-Nitrophenol Morphology dependence

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A Combined Reinforcement Learning and Model Predictive Control for Car-Following Maneuver of Autonomous Vehicles

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 315-325页

作者： Liwen wang Shuo Yang Kang yuan Yanjun huang hong Chen School of Automotive Studies Tongji UniversityShanghai 201804China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 201804China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

Model predictive control is widely used in the design of autonomous driving ***,its parameters are sensitive to dynamically varying driving conditions,making it difficult to be implemented into *** a result,this study presents a self-learning algorithm based on reinforcement learning to tune a model predictive ***,the proposed algorithm is used to extract features of dynamic traffic scenes and adjust the weight coefficients of the model predictive *** this method,a risk threshold model is proposed to classify the risk level of the scenes based on the scene features,and aid in the design of the reinforcement learning reward function and ultimately improve the adaptability of the model predictive controller to real-world *** proposed algorithm is compared to a pure model predictive controller in car-following *** to the results,the proposed method enables autonomous vehicles to adjust the priority of performance indices reasonably in different scenarios according to risk variations,showing a good scenario adaptability with safety guaranteed.

关键词： Model predictive control Reinforcement learning Autonomous vehicles

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Track-Pattern-Based Characteristics of Extratropical Transitioning Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric Sciences 2024年第6期41卷 1251-1263页

作者： hong huang Dan WU yuan wang Zhen wang Yu LIU College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China No.31631 Army of PLA Huizhou 516000China School of Atmospheric Sciences and Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing 210023China No.93721 Army of PLA Shuozhou 038300China

Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track *** characteristics of the six hard-clustered ETCs with the highest membership coefficient are *** tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these *** landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one *** frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four *** surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying *** results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.

关键词： Western North Pacific tropical cyclone extratropical transition fuzzy c-means clustering method

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A Gaussian Noise-Based Algorithm for Enhancing Backdoor Attacks

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Computers, Materials & Continua 2024年第7期80卷 361-387页

作者： hong huang Yunfei wang Guotao yuan Xin Li School of Computer Science and Engineering Sichuan University of Science&EngineeringYibin644000China

Deep Neural Networks(DNNs)are integral to various aspects of modern life,enhancing work ***-less,their susceptibility to diverse attack methods,including backdoor attacks,raises security *** aim to investigate backdoor attack methods for image categorization tasks,to promote the development of DNN towards higher *** on backdoor attacks currently faces significant challenges due to the distinct and abnormal data patterns of malicious samples,and the meticulous data screening by developers,hindering practical attack *** overcome these challenges,this study proposes a Gaussian Noise-Targeted Universal Adversarial Perturbation(GN-TUAP)*** approach restricts the direction of perturbations and normalizes abnormal pixel values,ensuring that perturbations progress as much as possible in a direction perpendicular to the decision hyperplane in linear *** limits anomalies within the perturbations improves their visual stealthiness,and makes them more challenging for defense methods to *** verify the effectiveness,stealthiness,and robustness of GN-TUAP,we proposed a comprehensive threat *** on this model,extensive experiments were conducted using the CIFAR-10,CIFAR-100,GTSRB,and MNIST datasets,comparing our method with existing state-of-the-art attack *** also tested our perturbation triggers using various defense methods and further experimented on the robustness of the triggers against noise filtering *** experimental outcomes demonstrate that backdoor attacks leveraging perturbations generated via our algorithm exhibit cross-model attack effectiveness and superior ***,they possess robust anti-detection capabilities and maintain commendable performance when subjected to noise-filtering methods.

关键词： Image classification model backdoor attack gaussian distribution Artificial Intelligence(AI)security

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Embedding copper nanoparticle-anchored conductive nano-blocks in polyelectrolyte

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Particuology 2013年第6期11卷 748-752页

作者： Qingsong Xu jianguo Tang Yao wang Jixian Liu Zhen huang Linjun huang Aihua Li yuan wang Laurence A.Belfiore Institute of Hybrid Materials Growing Base for State Key Laboratory of New Fiber and Modern TextileQingdao University Department of Chemical and Biological Engineering Colorado State University

Conductive carbon nanotubes （CNTs） or alternatively polyaniline （PANI） nano-blocks was introduced into aqueous solutions of polyvinyl alcohol （PVA） and copper （II） salt, to assist the reduction of copper （II） ions and the anchoring of the resulting copper nanoparticles onto the conductive blocks. The mixture solutions of nano-blocks, copper （lI） salts and PVA were spin-coated onto the cathode surface, forming swollen cathode films （SCFs）. The copper （II） ions in the film assembled onto the surfaces of the conductive blocks and were then reduced under an appropriate voltage. It is important that the copper nanoparticles grew only on the surfaces of the conductive blocks. PVA which acted as the matrix of the composites played a role in stabilizing the resulting copper nanoparticles. Morphologies of these polymeric composite films were studied by various characterization methods. Moreover, the mechanism of migration of copper （II） ions, the formation of these polymeric composites, and the overall procedure were investigated in detail.

关键词： Copper nanoparticles Carbon nanotubes Polyaniline Polyelectrolyte

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Decline in semen concentration of healthy Chinese adults： evidence from 9357 participants from 2010 to 2015

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Asian Journal of Andrology 2018年第4期20卷 379-384页

作者： hong-fang yuan huang-fang Shangguan Yi Zheng Tian-Qing Meng Cheng-Liang Xiong huang-Tao Guan Family Planning Research Institute Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China College of Informatics Huazhong Agricultural University Wuhan 430070 China Department of Venereology Wuhan Institute of Dermatology and Venereology Wuhan 430031 China Reproductive Medicine Center Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China Hubei Province Human Sperm Bank Wuhan 430030 China

The present study aims to analyze sperm concentration trends among young and healthy Chinese adults in Wuhan, Central China, from 2010 to 2015. Semen analysis data from 9357 participants were collected and analyzed using a general linear model and the Cochran-Armitage trend test. A significant decline was observed in sperm concentration （β [standard deviation]： -1.53 [0.16]; P 〈 0.001）. In addition, a decline in sperm density was observed by stratifying student versus nonstudent sperm donors and by analyzing the year of birth or birth year cohort of the participants. Furthermore, the percentage of participants with sperm densities of over 40×10^6 ml^-1 significantly decreased with year. Notably, a dramatic decline in sperm density was recorded over the first 5 years of study.

关键词： healthy men semen concentration sperm donors temporal trends

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Spectral Property and Thermal Quenching Behavior of Tb^(3+)-Doped YAG:Ce Phosphor

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Chinese Journal of Structural Chemistry 2016年第2期35卷 326-334页

作者： GUO wang SHI hong-ling huang Ji-Quan DENG Zhong-Hua yuan Xuan-Yi CAO Yong-Ge Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices Renmin University of China Key Lab of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences

A series of YAG：Ce,Tb phosphors were synthesized by vacuum sintering ***,their spectral properties,thermal quenching behaviors and color rendering properties were investigated *** photoluminescence emission spectra of YAG：Ce,Tb show a great red shift compared with that of YAG：*** energy transfer from Tb^（3＋） to Ce^（3＋） ions is verified based on the analysis of different photoluminescence *** quenching temperature for Tb^（3＋）-doped YAG：Ce phosphors is about 490 *** thermal activation energy is estimated to be 0.18 and 0.291 eV for Tb^（3＋）-doped YAG：Ce and YAG：Ce phosphors,*** smaller activation energy for Tb^（3＋）-doped YAG：Ce means a more rapid nonradiative transition from 5d to 4f state,thus resulting in the lower quenching *** addition,white LEDs with improved color rendering properties are achieved by using modified YAG：Ce,Tb phosphors.

关键词： YAG:Ce Tb phosphors spectra properties thermal quenching white LEDs

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