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Automatic Road Tunnel Crack Inspection Based on Crack Area Sensing and Multiscale Semantic Segmentation

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Computers, Materials & Continua 2024年第4期79卷 1679-1703页

作者： Dingping Chen Zhiheng Zhu Jinyang Fu jilin He College of Mechanical and Electrical Engineering Central South UniversityChangsha410083China department of Geotechnical Guangdong Hualu Transportation Technology Company LimitedGuangzhou510000China National Engineering Research Center of High-Speed Railway Construction Technology Changsha410075China

The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the surface of roadtunnels is the key to improving the maintenance efficiency of road tunnels. Machine vision technology combinedwith a deep neural network model is an effective means to realize the localization and identification of crackdefects on the surface of road *** propose a complete set of automatic inspection methods for identifyingcracks on the walls of road tunnels as a solution to the problem of difficulty in identifying cracks during manualmaintenance. First, a set of equipment applied to the real-time acquisition of high-definition images of walls inroad tunnels is designed. Images of walls in road tunnels are acquired based on the designed equipment, whereimages containing crack defects are manually identified and selected. Subsequently, the training and validationsets used to construct the crack inspection model are obtained based on the acquired images, whereas the regionscontaining cracks and the pixels of the cracks are finely labeled. After that, a crack area sensing module is designedbased on the proposed you only look once version 7 model combined with coordinate attention mechanism (CAYOLOV7) network to locate the crack regions in the road tunnel surface images. Only subimages containingcracks are acquired and sent to the multiscale semantic segmentation module for extraction of the pixels to whichthe cracks belong based on the DeepLab V3. network. The precision and recall of the crack region localizationon the surface of a road tunnel based on our proposed method are 82.4% and 93.8%, respectively. Moreover, themean intersection over union (MIoU) and pixel accuracy (PA) values for achieving pixel-level detection accuracyare 76.84% and 78.29%, respectively. The experimental results on the dataset show that our proposed two-staged

关键词： Road tunnel crack inspection crack area sensing multiscale semantic segmentation CA-YOLO V7 DeepLab V3.

Theoretical study on the reaction mechanism of (CH3.3.O(.) radical with NO

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Science china chemistry 2004年第4期47卷 289-294页

作者： ZHAO Hongmei1,2, LIU Kun1, SUN Chengke1 & LI Zonghe1 1. department of chemistry, Beijing Normal university, Beijing 100875,{3. 2. department of chemistry, beihua university, jilin 132013,{3. department of chemistry Beijing Normal University Beijing China department of chemistry Beihua University Jilin China

The reaction mechanism of (CH3.3.O? radical with NO is theoretically investigated at the B3.YP/6-3.G* level. The results show that the reaction is multi-channel in the single state and triplet state. The potential energy surfaces of reaction paths in the single state are lower than that in the triple state. The balance reaction: (CH3.3.ONO(CH3.3.O?+NO, whose potential energy surface is the lowest in all the reaction paths, makes the probability of measuring (CH3.3.O? radical increase. So NO may be considered as a stabilizing reagent for the (CH3.3.O? radical.

关键词： (CH3.3.O. radical DFT reaction mechanism NO

Study on the two and three-parameter working stability regions of 3.-TZP suspension

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Science china(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2, ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. department of chemistry, Qingdao university, Qingdao 266071,{3. 2. department of chemistry, Tsinghua university, Beijing 100084,{3. 3. department of Physics, Qingdao university, Qingdao 266071,{3. department of chemistry Qingdao University Qingdao China department of chemistry Tsinghua University Beijing China department of Physics Qingdao University Qingdao China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.

A local spin evaluation into the active site models of [2Fe2S] ferrodoxin [Fe_2S_2(SR)_4]^(2-) (R=-H, -CH_3.

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Science china chemistry 2007年第3期50卷 327-334页

作者： WEI JiChong1,2, WANG Yan3.& JU GuanZhi2,3.1 department of chemistry, Hainan Normal university, Haikou 571158,{3. 2 State Key Laboratory of Theoretical and Computational chemistry, jilin university, Changchun 13.023.{3. 3.department of chemistry, Nanjing university, Nanjing 210093.{3. department of chemistry Hainan Normal University Haikou China State Key Laboratory of Theoretical and Computational chemistry Jilin University Changchun China department of chemistry Nanjing University Nanjing China

To test the feasibility of local spin theory of Davidson and Clark for ferrodoxin clusters, the models [Fe2S2(SR)4]2- (R=-H, -CH3. are chosen for evaluation. This purpose is realized by calculating the local spin expectation values , , and mA and discussing the connection between these expected values and the Heisenberg spin model (HSM) and the Noodleman broken-symmetry approach. In practical calculation, the spin-unrestricted Hartree-Fock (UHF) and spin-polarized density functional theory (DFT) are used and the calculational qualities of these two methods are also discussed. In addition, the theoretical magnetic coupling constants JAB of these models are calculated by various computational schemes for comparison with both theoretical and experimental results previously reported.

关键词： local spin iron-sulfur protein model density function theory magnetic coupling constant

Integrative multi-omics approaches reveal that Asian cultivated rice domestication influences its symbiotic relationship with arbuscular mycorrhizal fungi

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Pedosphere 2024年第2期34卷 315-327页

作者： Lei TIAN jilin WANG Hongping CHEN Weiqiang LI Lam-Son Phan TRAN Chunjie TIAN Key Laboratory of Mollisols Agroecology State Key Laboratory of Black Soils Conservation and UtilizationNortheast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Rice Research Institute Jiangxi Academy of Agricultural SciencesNanchang 330200China Institute of Genomics for Crop Abiotic Stress Tolerance Department of Plant and Soil ScienceTexas Tech UniversityLubbock TX 79409USA

Potential changes in the symbiotic relationship between rice(Oryza sativa)and microorganisms have occurred during the domestication of Asian cultivated rice(***)from common wild rice(Oryza rufipogon)and in response to global climate change,along with evolving adaptations to the *** potential genes may express differently or dominate the symbiotic relationships between arbuscular mycorrhizal fungi(AMF)and plants,which may be beneficial to rice *** date,research on this important topic has been *** this study,we aimed to examine the symbiotic relationships of Asian common wild and cultivated rice species with *** conducting a comparative metagenomic analysis of the rhizospheres of wild and cultivated rice species,we identified differences in Rhizophagus intraradices-related genes associated with wild and cultivated rice,as well as functional genes of ***,we obtained root-related genes associated with AMF from transcriptome data of rice *** results collectively suggest that ***-related genes in the rhizosphere of wild rice may be more conducive to its ***,bacteria from the Nitrosomonadaceae and Nitrospiraceae families identified in the rhizosphere of wild rice exhibited positive correlations with ***-related genes with protein identifiers 1480749 and1871253.which may indicate that nitrobacteria can enhance the functions of *** in association with wild ***,in a case study using comparative transcriptome analysis of root samples obtained from ***-inoculated wild and cultivated rice plants,we found significantly higher expression levels of the strigolactone pathway-related genes DWARF3.D3.and DWARF14(D14)in ***-inoculated common wild rice than in ***-inoculated cultivated *** study provides a theoretical basis for identifying the effects of domestication on mycorrhizal symbiosis-related genes,which could be promoted in wi

关键词： Rhizophagus intraradices root-related gene symbiotic effect strigolactone wild rice

Syntheses,characterization,crystal structure and magnetic properties of copper(Ⅱ) α,β-unsaturated carboxylate complexes with trimethyl phosphate

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Chinese Science Bulletin 2001年第12期46卷 987-991页

作者： WANG Yaoyu, LIU Ping, SHI Qian, GAO Yici & SHI Qizhen1. department of chemistry, Northwest university, Xi’an 710069,{3. 2. department of chemistry, Wenzhou Teachers College, Wenzhou 3.5003.{3. 3. department of chemistry, Lanzhou university, Lanzhou 73.000,{3. department of chemistry Northwest University Xi’an China department of chemistry Wenzhou Teachers College Wenzhou China department of chemistry Lanzhou University Lanzhou China

Two ternary complexes Cu2A4[OP(OCH3.3.2 (A represents CH2=CH-COO- and CH2=C(CH3.-COO-) have been synthesized, and elemental analyses, IR, ESR, electronic reflectance spectra and magnetic studies were carried out. The single crystal X-ray diffraction shows that Cu2[CH2=C(CH3.-COO]4[OP(OCH3.3.2 is triclinic, with space group P1, a = 1.05128(13., b = 1.7559(5), c = 1.94479(3. nm, α =91.263.14)°,(β = 102.559(6)°,γ= 106.3.9(13.°, Z = 4 and R = 0.0668. Two copper(Ⅱ) atoms are bridged by four (a-methacrylate groups, and each copper(Ⅱ) atom is coordinated with a trimethyl phosphate molecule in the axial position, forming a distorted square pyramidal configuration. The symmetric center is between the two copper(Ⅱ) atoms, and the Cu-Cu bond distance is 0.26098(6) nm. The Cu-Cu distance and magnetic studies suggest that there exist anti-ferromagnetic interactions between the two copper(Ⅱ) atoms.

关键词： copper(Ⅱ ) complex α β-unsaturated carboxylate trimethyl phosphate magnetic property crystal structure.

Ship-in-bottle formation of Ru_3.CO)_(12) in NaY zeolite

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Chinese Journal of chemistry 1994年第3期12卷 258-264页

作者： XIAO, Feng-Shou XU, Ru-Ren HE, Ya-Nan department of chemistry, jilin {3., Changchun, jilin 13.023. china department of chemistry Jilin University Changchun Jilin 130023 China

NaY zeolite entrapped Ru3.CO)12 cluster has been synthesized from RuCl3.ion-exchanged NaY, which is well characterized by IR and Raman spectroscopies and CO chemisorp-tion. When the Ru3./NaY sample is heated from 298 K to 3.3.K for 25 h and for 10 h at 3.3.K, the sample colour changes from dark to brown-yellow. The in situ infrared spectrum exhibits absorption bands at 213., 2064, 2040, 2017, 1990, 1953.and 1925 cm-1. The bands at 213. cm-1 arises from the Runm+(CO)l m =1-3.n = 1 - 3. l = 1-12). The bands at 2064, 2040, 2017 and 1990 cm-1 are proposed to be associated with the Ru3.CO)12/NaY, which are close to Ru3.CO)12 crystalline. Furthermore, the Raman results provide bands at 150 and 185 cm-1, which can be attributed to Ru-Ru bonds of the sample as in the case of Ru3.CO)12 crystalline, for which the A1' Ru-Ru stretching mode is assigned to 185 cm-1 and E1' Ru-Ru stretching mode is assigned to a band at 150 cm-1, respectively. CO chemisorption of [Ru3./NaY gives a CO/Ru ratio of 3.85, which is similar to the stoichiometry of Ru3.CO)12.

关键词： Cluster ruthenium carbonyl NaY zeolite infrared Raman CO chemisorption.

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2, ZHANG Jiao qiang 3. (1. department of chemistry,Northwest university, Xi′an 710065,{3. 2. department of chemistry and Chemical Engineering, Baoji College of Arts and Science, Baoji 721007,{3. 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Simultaneously inducing synthesis of semiconductor selenium multi-armed nanorods and nanobars through bio-membrane bi-templates

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Science china chemistry 2004年第6期47卷 507-511页

作者： LI Li1, WU Qingsheng1 DING Yaping2 & LI Ping3.1. department of chemistry, Tongji university, Shanghai 200092,{3. 2. department of chemistry, Shanghai university, Shanghai 20043.,{3. 3. department of Food, Anhui Agricultural university, Hefei 23.03.,{3. department of chemistry Tongji University Shanghai China department of chemistry Shanghai University Shanghai China department of Food Anhui Agricultural University Hefei China

Multi-armed nanorods and nanobars of semiconductor selenium were simultane- ously synthesized in the light of biomineralization process through bio-membrane bi-templates of rush at room temperature. The multi-armed nanorods are 60 nm in diameter and 1.5 μm in length; the nanobars are 150 nm in diameter and 1000—1100 nm in length. The XRD pattern indicates that these nanocrystals were crystallized in the hexagonal structure with lattice constants a = 0.43. nm, c = 0.495 nm. The possible formation mechanism was investigated.

关键词： selenium, multi-armed nanorods, nanobars, bio-membrane, bi-templates.