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Unpaved road erosion after heavy storms in mountain areas of northern China

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International Soil and Water Conservation Research 2022年第1期10卷 29-37页

作者： Chunmei Wang Baoyuan Liu Qinke Yang Guowei Pang Yongqing Long Lei Wang Richard M.Cruse Weiqin Dang Xin Liu Enheng Wang Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental SciencesNorthwest UniversityXi'an710127PR China Key Laboratory of National forestry and Grassland Administration on Ecological Hydrology and Disaster Prevention in Arid Regions Xi'an710048PR China Advanced Institute of Natural Sciences Beijing Normal University at ZhuhaiZhuhai519087PR China State Key Laboratory of Earth Surface Processes and Resource Ecology School of GeographyBeijing Normal UniversityBeijing100875PR China Department of Agronomy Iowa State UniversityAmesIA50011USA Suide experimental Station for Soil and Water Conservation the Yellow River Conservancy CommissionYulinShaanxi719000PR China Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education Northeast Forestry UniversityHarbinHeilongjiang150040PR China

More frequent extreme rainfall events associated with global climate change cause greater challenges for soil *** erosion occurs on many unpaved roads since these structures create important water flow paths during heavy *** present research aimed to investigate the intensity and influencing factors of unpaved road erosion under varied land use and management conditions(sloping cropland,terraced cropland,forest&grass).The erosion occurred in the watersheds contributing runoff water to roads after the greatest rainfall event recorded in the mountain area of northern China caused by Typhon *** research was conducted in an agricultural-forest-dominated watershed based on field investigation and UAV-based image analysis.A road erosion level classification standard was given according to the occurrence of rills,ephemeral gullies,and *** erosion happened on 67% of the unpaved roads;42% of them suffered moderate to severe erosion in which ephemeral gullies or gullies *** average erosion amount from these roads was 2280.75 t ha-1 and was significantly influenced by the watershed land use type and *** dominant factor governing unpaved road erosion associated with terraced cropland was vegetation coverage on *** area was the most important factor for road erosion in sloping cropland and forest&grass land,and road gradient was also a critical ***,and forest&grass in drainage areas significantly reduced unpaved road erosion by 85%and,47%,respectively,compared to sloping *** integrated measures should be used to prevent unpaved road *** results of this research can be applied to road protection against erosion in heavy storms.

关键词： Unpaved road erosion Heavy storm Gully Land management Climate change

A novel image segmentation approach for wood plate surface defect classification through convex optimization

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Journal of forestry Research 2018年第6期29卷 1789-1795页

作者： Zhanyuan Chang Jun Cao Yizhuo Zhang College of Mechanical and Electrical Engineering Northeast Forestry University College of Information Mechanical and Electrical EngineeringShanghai Normal University

Detection of wood plate surface defects using image processing is a complicated problem in the forest industry as the image of the wood surface contains different kinds of defects. In order to obtain complete defect images, we used convex optimization(CO) with different weights as a pretreatment method for smoothing and the Otsu segmentation method to obtain the target defect area images. Structural similarity(SSIM) results between original image and defect image were calculated to evaluate the performance of segmentation with different convex optimization weights. The geometric and intensity features of defects were extracted before constructing a classification and regression tree(CART) classifier. The average accuracy of the classifier is 94.1% with four types of defects on Xylosma congestum wood plate surface: pinhole, crack,live knot and dead knot. experimental results showed that CO can save the edge of target defects maximally, SSIM can select the appropriate weight for CO, and the CART classifier appears to have the advantages of good adaptability and high classification accuracy.

关键词： Convex optimization Threshold segmentation Structure similarity Decision tree Defect recognition

Theoretical modeling of the effects of temperature and moisture content on the acoustic velocity of Pinus resinosa wood

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Journal of forestry Research 2018年第2期29卷 532-539页

作者： Shan Gao Xinmin Tao Xiping Wang Lihai Wang Northeast forestry University Harbin 150040People’s Republic of China USDA Forest Products Laboratory MadisonWI 53745USA

To investigate the effects of temperature and moisture content(MC) on acoustic wave velocity(AWV)in wood,the relationships between wood temperature,MC,and AWV were theoretically *** to the theoretical propagation characteristics of the acoustic waves in the wood mixture and the differences in velocity among various media(including ice,water,pure wood or oven-dried wood),theoretical relationships of temperature,MC,and AWV were established,assuming that the samples in question were composed of a simple mixture of wood and water or of wood and *** the theoretical model,the phase transition of AWV in green wood near the freezing point(as derived from previous experimental results) was plausibly *** comparative analysis between theoretical and experimental models for American red pine(Pinus resinosa) samples,it was established that the theoretically predicted AWV values matched the experiment results when the temperature of the wood was below the freezing point of water,with an averageprediction error of 1.66%.The theoretically predicted AWV increased quickly in green wood as temperature decreased and changed suddenly near 0 °C,consistent with the experimental *** prediction error of the model was relatively large when the temperature of the wood was above the freezing point,probably due to an overestimation of the effect of the liquid water content on the acoustic velocity and the limited variables of the *** high correlation between the predicted and measured acoustic velocity values in frozen wood samples revealed the mechanisms of temperature,MC,and water status and how these affected the wood(particularly its acoustic velocity below freezing point of water).This result also verified the reliability of a previous experimental model used to adjust for the effect of temperature during field testing of trees.

关键词： Acoustic velocity Wood Temperature Moisture content Theoretical model

Theoretical design of Catalytically Important Diuranium(Ⅲ) Complexes

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Theoretical design of Catalytically Important Diuranium(Ⅲ) ...

Comparative experimental study of machining characteristics of air-mixed EDM and conventional EDM

中国化学会第30届学术年会-第十八分会：电子结构理论方法的发展与应用

作者：潘清江郭元茹 Key Laboratory of Functional Inorganic Material Chemistry of Education Ministry School of Chemistry and Materials ScienceHeilongjiang University Key Laboratory of Bio-based Material Science and Technology of Education Ministry College of Material Science and EngineeringNortheast Forestry University

Understanding of reaction and structural property of diuranium(Ⅲ) complexes of a single ligand is essential to advancing their experimental synthesis and exploring promising applications in small molecule activation *** examined a series of diuranium(Ⅲ) complexes building on the reaction of[UI(THF)]and octadentate polypyrrolic ligands(HL and HL).At the relativistic density functional theory level,11.2 kcal/mol energy is required to form the Pacman-like[(UI)(μ-I)(L)](1) in THF solution,while only 0.5 kcal/mol for its non-classic Pacman isomer *** agree with their analogues that have been experimentally proposed.A variety of chemical modification has been made for *** addition of one THF solvent or one iodine ion raises reaction energy by 6.84.5 kcal/mol,while two or more are significantly *** energies of 1.4 and 7.4kcal/mol are required when varying bridged atom(from the iodine of 1 into the THF of 2[(UI)(μ-THF)(L)]) and lengthening ligand linker size(from ortho-phenylene of HL of 1 into anthracene of HL of 3[(UI)(μ-I)(L)]),*** diuranium(Ⅲ) complexes were optimized to be energetically *** U-U distances of 4.13 and 4.08 A were calculated for 1 and 2,respectively,compared with the long one of 5.90 A for 3.

关键词： polypyrrolic macrocycle diuranium(Ⅲ) complex thermodynamic calculation electronic structure relativistic DFT

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Journal of Harbin Institute of Technology(New Series) 2007年第2期14卷 170-173页

作者：李立青郭永丰白基成郭艳玲 School of Mechanical and Electrical Technology Northeast Forestry University School of Mechanical and Electrical Technology Harbin Institute of Technology Harbin 150001China School of Mechanical and Electrical Technology Harbin Institute of Technology

A new method of electrical discharge machining （EDM） in air-mixed medium--air-mixed EDM was presented, and comparative experiments were carried out to compare the machining characteristics of air-mixed EDM with conventional EDM. The experimental results showed that better machining performances were obtained with tool electrode as the cathode and workpieee as the anode. It was found that the material removal rate （MRR） was higher, the tool electrode relative wear ratio （TWR） was lower and the surface roughness （SR） quality was better in the case of air-mixed EDM than that of conventional EDM, and the reasons bringing out the results were analyzed.

关键词： EDM working dielectric air-mixed EDM machining characteristics

Identification of Symbiotic Bacteria on the Skin of Rana dybowskii

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Identification of Symbiotic Bacteria on the Skin of Rana dyb...

Detection and Identification of Tassel States at Different Maize Tasseling Stages Using UAV Imagery and Deep Learning

中国生理学会第24届全国会员代表大会暨生理学学术大会

作者： Zhang Jianping Zhang Jingyu Li Yu Xiao Xianghong Wang Jinghan Chai Longhui Northeast forestry University.College of wildlife resources

Amphibian populations in many parts of the world appear to be declining caused by infectious *** skin bacteria on healthy individuals may limit *** experimental have attempted to find the fungal pathogens cause of amphibians declines and the cutaneous antifungal bacteria species,but few of the natural bacteria flora resident on amphibian *** this study,we attempted to identify the natural bacteria flora that are resident species on amphibian *** bacteria were isolated from the cutaneous of healthy adult Rana dybowskii living in natural field sites in Tonghe and artificial culture field Baoquanling farm of heilongjiang province,*** identified bacterial genera by sequencing of the 16S r DNA gene,were related to Sphingomonas,Acinetobacter,Janthinobacterium,Comamonas,Ralstonia,Aquitalea,Chryseobacterium,Microbacterium,Brevundimonas,Aeromonas and *** examined the community-level physiological profiles（CLPP）of bacterial communities at these two sites of Rana *** was a highly difference of bacterial community similarity,and co-habitation individuals was not significant,highlighting that the skin-associated bacterial communities reflect those bacterial communities found in their surrounding *** cutaneous bacteria are a part of amphibians’innate immune system,form mutualistic ecological relationships with amphibian *** microbial community structure is a determinant of disease outcome.

关键词： Amphibian shin microflora CLPP

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Plant Phenomics 2024年第3期6卷 563-578页

作者： Jianjun Du Jinrui Li Jiangchuan Fan Shenghao Gu Xinyu Guo Chunjiang Zhao Information Technology Research Center Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Beijing Key Lab of Digital Plants National Engineering Research Center for Information Technology in AgricultureBeijing 100097China College of Information Engineering Northwest A&F UniversityYanglingShanxi 712100 China

The tassel state in maize hybridization fields not only reflects the growth stage of the maize but also reflects the performance of the detasseling *** tassel detection models are primarily used to identify mature tassels with obvious features,making it difficult to accurately identify small tassels or detasseled *** study presents a novel approach that utilizes unmanned aerial vehicles(UAVs)and deep learning techniques to accurately identify and assess tassel states,before and after manually detasseling in maize hybridization *** proposed method suggests that a specific tassel annotation and data augmentation strategy is valuable for substantial enhancing the quality of the tassel training *** study also evaluates mainstream object detection models and proposes a series of highly accurate tassel detection models based on tassel categories with strong data *** addition,a strategy for blocking large UAV images,as well as improving tassel detection accuracy,is proposed to balance UAV image acquisition and computational *** experimental results demonstrate that the proposed method can accurately identify and classify tassels at various stages of *** tassel detection model optimized with the enhanced data achieves an average precision of 94.5%across all *** optimal model combination that uses blocking strategies for different development stages can improve the tassel detection accuracy to 98%.This could be useful in addressing the issue of missed tassel detections in maize hybridization *** data annotation strategy and image blocking strategy may also have broad applications in object detection and recognition in other agricultural scenarios.

关键词： identification different learning imagery detection deep maize stages states tasseling

Stream water quality and its influencing factor in lower order streams in upriver sections of Ashihe River

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Journal of forestry Research 2005年第3期16卷 181-186页

作者： GUO Bao-qin WANG Qing-cheng YU Hong-li Paul E Mou forestry college of Northeast forestry University Harbin 150040 P. R China University of North Carolina at Greensboro NC 27402-6170 USA

For understanding the reasons that caused the degradation of water quality in lower order streams, systematic sampling was conducted at different spatial locations aiong the low order streams （1 st-5th） of Ashihe River continuum in Maoershan experimental Forest of Northeast forestry University, Sharlgzhi City, heilongjiang province, China. The indexes of stream water quality, i.e., the pH, dissolved oxygen（DO）, turbidity, temperature, PO43-P, NO3-N and NH4^＋-N concentrations, total dissolved inorganic nitrogen （TDIN-N, including concentrations of NO3^＋-N and NH4^＋-N）, and total phosphorus （inorganic and organic phosphorous, TP） were measured and analyzed. The stream order, related environmental settings and land-use type were recorded for each sampling location. The indexes of stream water quality at different locations with different stream orders and land use types were compared by ANOVA analysis. The indexes of stream water quality at different sampling locations were analyzed by Hierarchical cluster analysis. Result showed that water quality had significant difference in different stream orders and land use types; some locations with different stream features （stream order and land use type） were grouped into same clusters, indicating that random disturbances produced the variations in water quality, which made the spatial variances of stream water quality inconsistent with the general rules.

关键词： Stream water quality Land-use Stream order Hierarchical cluster analysis

Effect of Corrosive Ions (Cl^-,SO4^2-,and Mg^2+) on the Nanostructure and Chloride Binding Property of C-A-S-H Gel

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Journal of Wuhan University of Technology(Materials Science) 2020年第6期35卷 1061-1072页

作者： JIN Shucheng LIU Kai ZHANG Gaozhan SHI Hua DING Qingjun XU Wenyuan School of Civil Engineering Northeast Forestry UniversityHarbin 150040China China Construction Ready Mixed Concrete Co. LtdWuhan 430200China School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The nanostructure and chloride binding capacity evolution of C-A-S-H gel exposed to aggressive solutions were investigated,utilizing 29Si NMR,27Al NMR,SEM-EDS,and XRD *** experimental results show that while Cl-ions show a smaller effect on the microstructure of C-A-S-H sample,and SO4^2-ions can react with C-A-S-H,resulting in decreasing Ca/Si and Al[4]/Si for the C-A-S-H gel (i e,decalcification and dealuminization).The presence of Mg^2+ ions can aggravate the decalcifying and dealuminizing effects of SO4^2-ions on the *** decreasing Ca/Si ratio and aluminum substitution for the original C-A-S-H gel,the depolymerization degree of silicate tetrahedra increases and the calcium aluminosilicate skeleton strengthens.C-A-S-H gel with lower Ca/Si ratio and higher Al[4]/Si ratio shows gentler nanostructure evolution under chemical attack,i e,improving thermodynamic stability under chemical ***,the chloride binding capacity of C-A-S-H gel is decreased after the sulfate *** substitution can also help C-A-S-H gel resist the degraded chloride binding capacity induced by sulfate attack.

关键词： calcium-silicate-hydrate ions attack Ca/Si ratio Al/Si aluminum uptake