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Journal of Advanced Ceramics 2012年第1期1卷 60-65页

作者： yanjie zhang Jinjun LU Shengrong YANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Graduate School of the Chinese Academy of Sciences Beijing 100039China

Ultra-fine hydroxyapatite(HAp)powder with a diameter of about 10 nm was used as precursor for preparation of HAp *** precursor hydroxyapatite was single phase and highly crystallized without any additional thermal *** densified HAp ceramic was fabricated through centrifugal infiltration casting(CIC),followed by pressureless *** relative densities of compacts prepared at 1100°C and 1200°C were 77.8%and 94.1%,*** micrographs of HAp ceramic sintered at 1100°C showed a porous microstructure with a grain size of 1μ*** ceramic fabricated at 1200°C revealed a dense microstructure with nano-sized sphericalα-TCP distributed at grain boundaries and triple *** mechanism of decomposition from HAp toα-TCP at 1200°C was discussed on the basis of SEM,XRD and FTIR results.

关键词： hydroxyapatite bioceramics Centrifugal Infiltration Casting pressureless sintering

Fluid-solid coupling numerical simulation of micro-disturbance grouting treatment for excessive deformation of shield tunnel

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Underground Space 2024年第6期19卷 87-100页

作者： yanjie zhang Zheng Cao Chun Liu Hongwei Huang College of Civil Engineering and Architecture Henan University of TechnologyZhengzhou 450001China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

Micro-disturbance grouting is a recovery technique to reduce the excessive deformation of operational shield tunnels in urban *** grout mass behaves as a fluid in the ground before hardening to form a grout–soil mixture,which highlights the necessity of using fluid–solid coupling method in the simulation of grouting *** a discrete element modeling environment,this paper proposes a novel fluid-solid coupling method based on the pore density flow *** demonstrate the effectiveness of this method,it is applied to numerical simulation of micro-disturbance grouting process for treatment of large transverse deformation of a shield tunnel in Shanghai Metro,*** simulation results reveal the mechanism of recovering tunnel convergence by micro-disturbance grouting in terms of compaction and fracture of soil,energy analysis during grouting,and mechanical response of soil-tunnel interaction ***,the influence of the three main grouting parameters(i.e.,grouting pressure,grouting distance,and grouting height)on tunnel deformation recovery efficiency is evaluated through parametric *** order to efficiently recover large transverse deformation of shield tunnel in Shanghai Metro,it is suggested that the grouting pressure should be about 0.55 MPa,the grouting height should be in the range of 6.2–7.0 m,and the grouting distance should be in the range of 3.0–3.6 *** results provide a valuable reference for grouting treatment projects of over-deformed shield tunnel in soft soil areas.

关键词： Fluid-solid coupling Discrete element method Pore density flow Micro-disturbance grouting Soil-tunnel interaction

Elemental composition and risk assessment of heavy metals in the PM10 fractions of road dust and roadside soil

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Particuology 2019年第3期17卷 146-152页

作者： Jing zhang Lin Wu yanjie zhang Fenghua Li Xiaozhen Fang Hongjun Mao Center for Urban Transport Emission Research (CUTER) College of Environmental Science and Engineering Nankai University Tianjin 300071 China Tianjin Eco-Environmental Monitoring Center Tianjin 300191 China Tianjin-Tianbinruicheng Environmental Technology and Engineering Co. Ltd. Tianjin 300190 China Nankai University Weijin Road 94. Tianjin 300071 China

A total of 64 dust samples were analyzed to determine the size distribution and elemental composition of the PM10 fraction, including42 road dust(RD), 12 roadside soil(RSD), and 10 park road dust(PRD) samples. The mass of dust smaller than 20μm was dominated by particles sized 2.5-16 μm, which accounted for 85%, 88%, and 87% of the RD, PRD, and RSD, respectively. Additionally, crustal elements accounted for 30.14%, 36.35%, and 37.14% of the PMio fractions of the RD, RSD, and PRD, respectively. The most abundant trace elements in RD, RSD, and PRD were Zn, Mn, and Cu (range, 277 to 874 mg/kg). Moreover, the /geo values revealed all dusts were contaminated with Pb, Zn, Cu, Sb, Sn, and Cd. Health risk assessment showed that Mn, Ni, Cu, Zn, Cd, Sb, and Pb in the PM10 fraction of three types of dusts posed non-cancer risks to children but posed no non-cancer risk to adults. Additionally, As, Ni, and Cd posed no cancer risk to inhabitants.

关键词： Road dust Mass size distribution PM10 Elemental composition Health risk assessment

MYB56 Encoding a R2R3 MYB Transcription Factor Regulates Seed Size in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2013年第11期55卷 1166-1178页

作者： yanjie zhang Wanqi Liang Jianxin Shi Jie Xu Dabing zhang School of Life Sciences and Biotechnology Shanghai Jiao Tong University

Plant seed size is tightly regulated by the development of seed coat, embryo, and endosperm; however, currently, its underlying mechanism remains unclear. In this study, we revealed a regulatory role of an R2R3 MYB transcription factor MYB56 in controlling seed size specifically in Arabidopsis thaliana L. Loss- of-function or knock-down of MYB56 yielded smaller seeds as compared with the wild type. Conversely, overexpression of MYB56 produced larger seeds. Further observation using semi-thin sections showed that myb56 developed smaller contracted endothelial cells and reduced cell number in the outer integument layer of the seed coat during the seed development; by contrast, MYB56 overexpressing lines had expanded endothelial cells and increased cell number in the outer integument layer of the seed coat, suggesting the essential role of MYB56 in regulating seed development. In addition, reciprocal cross- analysis showed that MYB56 affected the seed development maternally. MYB56 was shown to be dominantly expressed in developing seeds, consistently with its function in seed development. Moreover, quantitative reverse transcription polymerase chain reaction analysis revealed that MYB56 regulates the expression of genes involved in cell wall metabolism such as cell division and expansion. Altogether, our results demonstrated that MYB56 represents an unknown pathway for positively controlling the seed size.

关键词： Cell wall endothelium MYB seed coat seed size.

Effects of antibiotics on corncob supported solid-phase denitrification: Denitrification and antibiotics removal performance, mechanism, and antibiotic resistance genes

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Journal of Environmental Sciences 2023年第8期130卷 24-36页

作者： yanjie zhang Weiyang Dong Congyu Li Haiyan Wang Huan Wang Yu Ling Guokai Yan Yang Chang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Research Center of Environmental Pollution Control Technology Chinese Research Academy of Environmental ScienceBeijing 100012China

Solid-phase denitrification(SPD)has been used in wastewater treatment plant effluent to enhance nitrate removal,and antibiotics co-existing in the effluent is a common environmental *** this study,it was systematically investigated the effect of single trace sulfamethoxazole(SMX)/trimethoprim(TMP)and theirmixture on microbial denitrification performance,the antibiotics removal,and antibiotics resistance genes(ARGs)in corncob supported SPD *** average denitrification rate was improved by 46.90%or 61.09%with single 50μg/L SMX or TMP,while there was no significant inhibition with mixed SMX and *** abundance of dominant denitrifiers(Comamonadaceae family and Azospia)and fermentation bacteria(Ancalomicrobium)were consistent with the denitrification performance of different antibiotics *** SMX and TMP achieved relatively higher denitrification gene and enzyme *** SMX and TMP improved the denitrification gene copies,but they reduced the key denitrification enzymes except for EC ***,the removal efficiency of TMP(56.70%±3.18%)was higher than that of SMX(25.44%±2.62%)in single antibiotic group,and the existence of other antibiotics(*** or TMP)had no significant impact on the TMP or SMX removal *** was the main removal mechanism of SMX and TMP,while sludge and corncob adsorption contributed a little to their *** had the risk of sulfanilamide resistance genes(SRGs)***,network analysis indicated that Niveibacterium and Bradyrhizobium were the potential hosts of SRGs,which promoted the horizontal transmission of ARGs.

关键词： Solid-phase denitrification(SPD) Sulfamethoxazole (SMX)/trimethoprim(TMP) Microbial community Denitrification genes Antibiotics resistance genes(ARGs)

Resonance and Bifurcation of Fractional Nonlinear Systems with Power Damping Term for Robot Grinding

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Journal of Beijing Institute of Technology 2023年第1期32卷 23-40页

作者： Wei Shi Qingxue Huang Jinzhu zhang Tao Wang Ziliang Li yanjie zhang Xiaoyan Xiong College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China Institute of Advanced Forming and Intelligent Equipment Taiyuan University of TechnologyTaiyuan 030024China

A fractional nonlinear system with power damping term is introduced to study the forced vibration system in order to solve the resonance and bifurcation problems between grinding wheel and steel bar during robot *** robot,grinding wheel and steel bar are reduced to a spring-damping second-order system *** implicit function equations of vibration amplitude of the dynamic system with coulomb friction damping,linear damping,square damping and cubic damping are obtained by average *** stability of the system is analyzed and explained,and the stability condition of the system is ***,the amplitude-frequency characteristic curves of the system under different fractional differential orders,nonlinear stiffness parameters,fractional differential term coefficients and external excitation amplitude are *** is shown that the fractional differential term in the dynamic system is the damping *** the influence of four kinds of damping on the vibration amplitude of the system under the same parameter is investigated and it is proved that the cubic damping suppresses the vibration of the system to the maximum ***,based on the idea that the equilibrium point of the system is the constant part of the Fourier series expansion term,the bifurcation behavior caused by the change of damping parameters in linear damping,square damping and cubic damping systems with different values of fractional differential order is investigated.

关键词： robot grinding fractional system average method power damping resonance and bifurcation

Clinical management of a rare melanoma case arising from congenital melanocytic nevus

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Genes & Diseases 2024年第3期11卷 79-82页

作者： Ruixin Jiang Yan Wang Xuhui Ma Xinyang Xuanyuan yanjie zhang Bin Jiang Weizhen zhang Hanlin Zeng Department of Oncology Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai 201900China Department of Oncology The Third People's Hospital of ZhengzhouZhengzhouHenan 450000China Department of Oral&Maxillofacial-Head and Neck Oncology Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai 200125China Shanghai Institute of Precision Medicine Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai200125China Department of Dermatology Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineShanghai 200000China

Congenital melanocytic nevi(CMNs)are skin lesions characterized by benign melanocytic proliferations and present at birth or shortly *** and giant CMNs,with a projected adult size≥20 cm and 40 cm in diameter respectively,are more likely to develop into malignant *** most cases,melanoma arising from congenital melanocytic nevus(CMN)is particularly aggressive.

关键词： melanoma congenital melan

Design and physical model experiment of an attitude adjustment device for a crawler tractor in hilly and mountainous regions

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Information Processing in Agriculture 2020年第3期7卷 466-478页

作者： Jingbin Sun Chong Meng Yazhou zhang Guoping Chu yanjie zhang Fuzeng Yang Zhijie Liu College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China Scientific Observing and Experimental Station of Agricultural Equipment for the Northern China Ministry of Agriculture PR ChinaYanglingShaanxi 712100China State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau YanglingShaanxi 712100China

To address the problems of difficult leveling and poor stability of hill crawler tractors,an attitude adjustment device based on a parallel four-bar mechanism was designed,and the mechanical reasons for the sideslip instability of hill crawler tractors were *** this basis,a posture adjustment mechanism based on a parallel four-bar mechanism was proposed,and the structure of the complete attitude adjustment device was *** ensure that this device meets the strength requirements during operation,a mechanical analysis of the key components(active rocker and slave rocker)was carried out to accommodate the load during *** on ANSYS software,a finite element simulation analysis was used to determine the maximum stress position of the active and slave ***,to verify the accuracy of the above simulation analysis results and determine the influence rules of the lateral slope angle,longitudinal slope angle and loading quality on the abovementioned maximum stress,a physical model test bench of the attitude adjustment device was *** orthogonal regression experiment was carried out with the maximum stresses of the active and slave rockers as the test *** experimental data were analyzed by Design-Expert 10 software,and the results show that the order of the primary and secondary factors influencing the maximum stress of the active rocker was the loading mass,lateral slope angle and longitudinal slope *** order of the factors influencing the maximum stress of the slave rocker was the longitudinal slope angle,lateral slope angle and loading *** active and slave rockers meet the strength *** work provides technical support for the production of hill crawler tractor physical prototypes.

关键词： Hill crawler tractor Attitude adjustment Mechanical analysis Physical model experiment

Health risk assessments of polycyclic aromatic hydrocarbons and chlorinated/brominated polycyclic aromatic hydrocarbons in urban air particles in a haze frequent area in China

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Emerging Contaminants 2020年第1期6卷 172-178页

作者： Miwei Shi Rongzhi zhang Yunxia Wang Yan zhang Yuan zhang yanjie zhang Institute of Geographical Science Hebei Academy of SciencesEngineering Technology Research Center of Geographic Information Development and Application of HebeiShijiazhuang050011China

The potential threats of polycyclic aromatic hydrocarbons(PAHs)and chlorinated/brominated PAHs(Cl/Br-PAHs)to human health from particulate matter in the urban ambient air were studied using human health risk *** risk to human health caused by exposure to PAHs was evaluated in Shijiazhuang,China,from January to December *** PAHs concentration range was 16.02e475.21 ng/m3 and the toxic equivalent was 13.605 ng/*** adults,the average carcinogenic risk caused by respiratory exposure was 5.163×10^-6 and the resulting loss of life expectancy was 32.10 *** human health risks of respiratory exposure to Cl/Br-PAHs in atmospheric samples from the Haidian District,Beijing,China,were evaluated from November 2017 to July *** concentration ranges for the Cl-and Br-PAHs were 60.38e482.17 pg/m3 and 1.32e25.35 pg/m3,*** average carcinogenic equivalent concentrations were 0.3274 pg/m3 and 0.0061 pg/m3 for the Cl-and Br-PAHs,*** adults the average carcinogenic risks caused by respiratory exposure were 1.243×10^-10 and 2.316×10^-12 for the Cl-and Br-PAHs,*** resulting loss of life expectancy values were 0.001 min(Cl-PAHs)and 0.00 min(Br-PAHs).The pollution concentrations and toxic equivalents of the Cl/Br-PAHs in Beijing and of the PAHs in Shijiazhuang both showed toxicity was high in the *** average carcinogenic risk for exposure of adults to PAHs in Shijiazhuang was low with certain potential *** concentration of Cl-PAHs in Beijing was higher than that of Br-PAHs,and the average carcinogenic risk for exposure of adults to Cl/Br-PAHs was very low with slight harm.

关键词： Particulate matter Persistent organic pollutant Polycyclic aromatic hydrocarbon Chlorinated/brominated polycyclic aromatic hydrocarbon Health risk assessment

A 14 nucleotide deletion mutation in the coding region of the PpBBX24 gene is associated with the red skin of“Zaosu Red”pear(Pyrus pyrifolia White Pear Group):a deletion in the PpBBX24 gene is associated with the red skin of pear

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Horticulture Research 2020年第1期7卷 2185-2198页

作者： Chunqing Ou Xiaoli zhang Fei Wang Liyi zhang yanjie zhang Ming Fang Jiahong Wang Jixun Wang Shuling Jiang Zhihong zhang College of Horticulture Shenyang Agricultural UniversityShenyang110161 LiaoningPR China Key Laboratory of Horticultural Crops Germplasm Resources Utilization Ministry of AgricultureResearch Institute of PomologyChinese Academy of Agricultural SciencesXingcheng125100 LiaoningPR China Xinjiang Fruit Science Experiment Station Ministry of Agriculture and Rural AffairsHorticultural Crops Research InstituteXinjiang Academy of Agricultural SciencesUrumqi830091 XinjiangPR China Biomarker Technologies Corporation Beijing101300PR China

Red skin is an important quality trait for pear fruits and is determined by the concentration and composition of *** regulatory mechanism underlying anthocyanin accumulation is a popular topic in fruit *** mutants are ideal materials for studying the molecular mechanism of color diversity in *** several red pear mutants have been cultivated and are in production,no exact locus containing the responsible genetic mutation has been *** this study,by combining the bulked segregant analysis with whole-genome sequencing,we identified a 14 nucleotide deletion mutation in the coding region of the PpBBX24 gene from the red pear mutant“Zaosu Red”.We further verified that the deletion was present only in the red mutant of“Zaosu”and in its red offspring,which was different from that which occurred in other red pear *** deletion results in a coding frame shift such that there is an early termination of the PpBBX24 gene and loss of key NLS and VP domains from *** lost domains may reduce or alter the normal function of *** addition,we found that the transcript levels of the PpMYB10 and PpHY5 genes in red samples were significantly higher than those in green samples,whereas the results for the normal-type PpBBX24 gene were the *** ultimately revealed that the 14 nucleotide deletion mutation in the coding region of the PpBBX24 gene is associated with the red skin of the“Zaosu Red”*** finding of somatic mutational events will be helpful for breeding new red pear cultivars and for understanding the regulatory mechanisms involved in pear skin pigmentation.

关键词： breeding cultivar cultivated