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Defence Technology（防务技术） 2024年第1期31卷 27-40页

作者： Rui Liu Danfeng Yang Kunyu Xiong ying-Lei wang Qi-Long Yan Science and Technology on Combustion Internal Flow and Thermo-structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China Xi'an Modern Chemistry Research Institute Xi'an710065China

Boron has high mass and volume calorific values,but it is difficult to ignite and has low combustion *** literature review summarizes the strategies that are used to solve the above-mentioned problems,which include coatings of boron by using fluoride compounds,energetic composites,metal fuels,and metal *** techniques include recrystallization,dual-solvent,phase transfer,electrospinning,*** one of the effective coating agents,the fluorine compounds can react with the oxide shell of boron *** comparison,the energetic composites can effectively improve the flame temperature of boron powder and enhance the evaporation efficiency of oxide film as a condensed *** and metal oxides would react with boron powder to form metal borides with a lower ignition point,which could reduce its ignition temperature.

关键词： Boron powder coating Structure and morphology Condensed phase thermal reaction Ignition and combustion

Structure design and rice threshing performance of the variable-speed inertial pulley for simulating artificial threshing

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 33-40页

作者： Tiantian Jing zhong Tang Shuaihua Hao Cheng Shen Ting wang Meilin wang School of Agricultural Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province Hangzhou 310058China College of Engineering China Agricultural UniversityBeijing 100083China Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China Jiangsu World Agriculture Machinery Co. Ltd(WORLD A/M)Zhenjiang 212311JiangsuChina

Due to the small models and compact structures,small harvesters have also caused problems such as poor threshing separation performance and large loss *** order to solve unstable cleaning effects of small harvesters when they facing different working conditions,this study selected rice plants in hilly areas for the *** breaking force of different parts of mature rice was tested,which revealed the fracture mechanism of each part under the combined *** threshing method was used to simulate artificial plate bin and design three kinds of non-circular pulley variable speed transmission threshing *** the help of transient inertia force,threshing force was *** paper tested the harvesting performance of the variable speed threshing device with the help of the harvest performance *** show when facing the small rice planting area,the T/2 variable speed threshing device has better cleaning performance,and also the harvest loss rate of T/4 variable speed threshing device is the *** with the constant speed threshing device,the impurity content rate of the variable speed threshing device is increased by 0.64%to 8.76%;the loss rate is reduced by 0.45%to 1.79%,which provides a basis for the optimization design of small combine harvester in hilly areas.

关键词： small harvesters fracture mechanism transient inertia force non-circular pulley

Rice stem lodging properties and bending modeling under the influence of circadian temperature difference

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 21-32页

作者： Bangzhui wang zhong Tang Liyun Lao Guoqiang wang Tiantian Jing Yao Yu School of Agricultural Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina School of Water Energy and EnvironmentCranfield UniversityMK430ALUK Department of Agricultural Engineering Jiangsu Agriculture&Animal Husbandry Science and Technology Vocational CollegeTaizhou 225300JiangsuChina

Under diurnal temperature stress,the vascular bundle content of mature rice stems will change which will cause a change in the modulus of ***,the rice stems will collapse with the reduction in bending resistance because of the change in the modulus of *** order to reveal the distribution of vascular bundle gradients in rice stems under different climatic temperatures and explore the locations where stems are prone to bending and the form of stem damage,this study established a model of stem stiffness under free loading based on observing microstructure of the *** lodging characteristics of rice stems was explored seldom in different environmental temperatures from a micro structure of rice ***,the statistical analysis and t-tests were carried out on stems 1 to 4 in combination for cantilever bending tests at room temperature on stem internodes 3,versus three-point bending tests at-10℃ to 65℃ temperature *** showed that the bending resistance of the stem can be well predicted by using the vascular bundle distribution regression model and the variable stiffness mechanical *** bending resistance of No.3 stem was established by using the results obtained from the three-point bending test in a temperature range between 10℃-65℃.The correction coefficient TF of stem bending resistance under temperature difference induced stress was established based on the Gauss regression *** analysis showed that the bending resistance of No.3 stem was relatively large in a temperature range of 16℃-34℃.This study elucidated the variations of the mechanical properties of rice stems under temperature difference induced stress and provided a theoretical foundation for understanding the lodging characteristics of rice during mechanized harvesting.

关键词： rice stem vascular gradient stiffness model stem bending temperature stress

Migration and transformation of Pb,Cu,and Zn during co-combustion of high-chlorine-alkaline coal and Si/Al dominated coal

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Journal of Environmental Sciences 2024年第7期141卷 26-39页

作者： Jiangze Luo Qiwei Yang Jianqiao wang Boxiong Shen Zhuozhi wang Qiqi Shi zhong Zhao Chao Huang Jie Xu Tianjin Key Laboratory of Clean Energy and Pollution Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin 300103China School of Chemical Engineering Hebei University of TechnologyTianjin 300103China

Shaerhu(SEH)coal is abundant in Xinjiang,*** utilization of SEH suffers from severe ash deposition,slagging,and fouling problems due to its high-chlorine-alkaline *** co-combustion of high-alkaline coal and other type coals containing high Si/Al oxides has been proven to be a simple and effective method that will alleviate ash-related problems,but the risk of heavy metals(HMs)contamination in this process is ***,the volatilization rates and chemical speciation of Pb,Cu,and Zn in co-combusting SEH and a high Si/Al oxides coal,i.e.,Yuanbaoshan(YBS)coal were investigated in this *** results showed that the addition of SEH increased the volatilization rates of Pb,Cu,and Zn during the co-combustion at 800℃from 23.70%,23.97%,and 34.98%to 82.31%,30.01%,and 44.03%,respectively,and promoted the extractable state of Cu and *** addition,the interaction between SEH and YBS inhibited the formation of the Pb residue ***-EDS mapping results showed that compared to Zn and Cu,the signal intensity of Pb was extremely weak in regions where some of the Si and Al signal distributions *** DFT results indicated that the O atoms of the metakaolin(Al_(2)O_(3)·2SiO_(2))(001)surface were better bound to the Zn and Cu than Pb atoms after adsorption of the chlorinated *** results contribute to a better understanding of the effects of high-alkaline coal blending combustion on Pb,Cu,and Zn migration and transformation.

关键词： Heavy metals High-chlorine-alkaline coal Coal blending combustion Density functional theory

MTA1表达与中国肺癌患者预后关系的meta分析

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中国肺癌杂志 2017年第10期20卷 683-689页

作者：钟海唐云王英谷伟南京医科大学附属南京医院呼吸科南京210006

背景与目的已有的研究表明:在多种恶性肿瘤中发现转移相关蛋白1(metastasis associated protein1,MTA1)发挥着促进肿瘤侵袭与转移的作用,且与肿瘤患者预后不佳有关。目前MTA1在肺癌中的预后作用仍有争议,故我们采用meta分析的方法评估... 详细信息

背景与目的已有的研究表明:在多种恶性肿瘤中发现转移相关蛋白1(metastasis associated protein1,MTA1)发挥着促进肿瘤侵袭与转移的作用,且与肿瘤患者预后不佳有关。目前MTA1在肺癌中的预后作用仍有争议,故我们采用meta分析的方法评估其在肺癌患者中的预后价值。方法通过计算机检索PubMed、Embase、万方数据库、中国生物医学文献数据库、中国知网等数据库,收集纳入研究MTA1表达与肺癌预后关系的文献及相关数据,采用Stata 12.0软件进行数据分析,合并值为风险比(hazard ratio,HR)。结果总共纳入8项研究共712例中国肺癌患者,对这些研究进行异质性检验,发现存在异质性(I^2=59.0%,P=0.017),故采用随机效应模型进行数据合并得HR=2.07(95%CI:1.42-3.02,P<0.001)。同时分层分析显示在非小细胞肺癌(non-small cell lung cancer,NSCLC)中各研究无明显异质性(I^2=47.0%,P=0.093),采用固定效应模型合并得HR=1.66(95%CI:1.27-2.18,P<0.001)。结论 MTA1高表达可能是中国NSCLC患者预后不良的一个指标,在肺癌及小细胞肺癌中的预后价值尚缺乏证据。

关键词：肺癌 MTA1 预后 Meta分析

Degree of shade tolerance shapes seasonality of chlorophyll, nitrogen and phosphorus levels of trees and herbs in a temperate deciduous forest

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Journal of Forestry Research 2024年第4期35卷 60-72页

作者： Jiajia Zeng Fan Liu Yuan Zhu Jiayi Li ying Ruan Xiankui Quan Chuankuan wang Xingchang wang Aulin College Northeast Forestry UniversityHarbin 150040People’s Republic of China Center for Ecological Research Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021People’s Republic of China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China

Forest productivity is closely linked to seasonal variations and vertical differentiation in leaf ***,leaf structural and chemical traits variation among co-existing species,and plant functional types within the canopy are poorly *** this study,the seasonality of leaf chlorophyll,nitrogen(N),and phosphorus(P)were quantified vertically along the canopy of four major tree species and two types of herbs in a temperate deciduous *** role of shade tolerance in shaping the seasonal variation and vertical differentiation was *** the entire season,chlorophyll content showed a distinct asymmetric unimodal pattern for all species,with greater chlorophyll levels in autumn than in spring,and the timing of peak chlorophyll per leaf area gradually decreased as shade tolerance *** a:b ratios gradually decreased with increasing shade *** N and P contents sharply declined during leaf expansion,remained steady in the mature stage and decreased again during leaf *** the seasons,the lower canopy layer had significantly higher chlorophyll per leaf mass but not chlorophyll per leaf area than the upper canopy layer regardless of degree of shade ***,N and P per leaf area of intermediate shade-tolerant and fully shade-tolerant tree species were significantly higher in the upper canopy than in the *** variations in N:P ratios suggest changes in N or P *** findings indicate that shade tolerance is a key feature shaping inter-specific differences in leaf chlorophyll,N,and P contents as well as their seasonality in temperate deciduous forests,which have significant implications for modeling leaf photosynthesis and ecosystem production.

关键词： Leaf traits Leaf nutrients Seasonal variations Chlorophyll Nitrogen Phosphorus Shade tolerance Canopy layers

Hypermethylation of the ALOX12 and CBS promoters in osteoporosis:Potential biomarkers for early diagnosis

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Genes & Diseases 2024年第1期11卷 30-33页

作者： Shang Guo Yue Wu Weekai Chia Peichun Hsu Hongwei wang Yunliang wang Biao zhong Department of Orthopedic Surgery Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200023China Institute of Translational Medicine Shanghai General HospitalShanghai Jiao Tong University School of Medicine(SJTU-SM)Shanghai 200025China The University of Chicago Department of MedicineChicagoIL 60637USA Department of Neurology The Second Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450014China

As a bone-confined chronic degenerative disorder,the progression of osteoporosis is characterized by abnormal crosstalk between osteoblasts and osteoclasts,leading to an imbalance of bone remodeling in adults.1 Several studies reported that arachidonic acid ester 12 lipoxygenase(ALOX12)acts as a regulator in bone genesis by participating in the activation of the peroxisome proliferatoractivated receptor(PPARG)pathway through its reaction product.

关键词： osteoporosis diagnosis remodeling

Transient Analysis of a Reactor Coolant Pump Rotor Seizure Nuclear Accident

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1331-1349页

作者： Mengdong An Weiyuan zhong Wei Xu Xiuli wang Research Center of Fluid Machinery Engineering and Technology Zhenjiang212013China School of Energy and Power Engineering Jiangsu UniversityZhenjiang212013China

The reactor coolant pump(RCP)rotor seizure accident is defined as a short-time seizure of the RCP *** event typically leads to an abrupt flow decrease in the corresponding loop and an ensuing reactor and turbine *** significant reduction of core coolant flow while the reactor is being operated at full load can have very negative *** potentially dangerous event is typically characterized by a complex transient behavior in terms of flow conditions and energy transformation,which need to be analyzed and *** study constructed transient flow and rotational speed mathematical models under various degrees of rotor seizure using the test data collected from a dedicated transient rotor seizure test ***,bidirectional fluid-solid coupling simulations were conducted to investigate the flow evolution *** is found that the influence of the impeller structure size and transient braking acceleration on the unsteady head(Hu)is dominant in rotor seizure accident ***,the present results also show that the rotational acceleration additional head(Hu1)is much higher than the instantaneous head(Hu2).

关键词： Reactor coolant pump bidirectional fluid-solid coupling rotor seizure nuclear accident

Dimensional regulation in gigantic molybdenum blue wheels featuring{(W)Mo_(5)}motifs for enhanced proton conductivity

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Nano Research 2024年第9期17卷 8261-8268页

作者： Yu-Lun Wu Jing Du Hai-ying Zhang Ming-Jun Hou Qiao-Yue Li Wei-Chao Chen Kui-Zhan Shao Bo Zhu Chao Qin Xin-Long wang zhong-Min Su Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Department of ChemistryNortheast Normal UniversityChangchun 130024China Hebei Key Laboratory of Organic Functional Molecules National Demonstration Center for Experimental Chemistry EducationTesting and Analysis CenterCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China

Dimensional regulation in polyoxometalates is an effective strategy during the design and synthesis of polyoxometalates-based high proton conductors,but it is not available to ***,the precise regulation of dimensionality has been realized in an unprecedented gigantic molybdenum blue wheel family featuring pentagonal{(W)Mo5}motifs through optimizing the molar ratio of Mo/W,including[Gd_(2)Mo_(124)W_(14)O_(422)(H_(2)O)62]38-(0D-{Mo_(124)W_(14)},1),[Mo_(126)W_(14)O441(H_(2)O)51]^(70-)(1D-{Mo_(126)W_(14)}n,2),and[Mo_(124)W_(14)O_(430)(H_(2)O)50]60-(2D-{Mo_(124)W_(14)}n,3).Such important{(W)Mo5}structural motif brings new reactivity into gigantic Mo blue *** are different numbers and sites of{Mo2}defects in each wheel-shaped monomer in 1-3,which leads to the monomers of 2 and 3 to form 1D and 2D architectures via Mo-O-Mo covalent bonds driven by{Mo2}-mediated H_(2)O ligands substitution process,respectively,thus achieving the controllable dimensional *** expected,the proton conductivity of 3 is 10 times higher than that of 1 and 1.7 times higher than that of *** continuous proton hopping sites in 2D network are responsible for the enhanced proton conductivity with lower activation *** study highlights that this dimensional regulation approach remains great potential in preparing polyoxometalates-based high proton conductive materials.

关键词： polyoxometalate molybdenum blue wheels Mo/W mixed-addenda polyoxometalates dimensional regulation proton conduction

Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin

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Petroleum Science 2024年第1期21卷 115-124页

作者： Wen-Yang wang Xiong-Qi Pang Ya-Ping wang Zhang-Xin Chen Fu-Jie Jiang ying Chen State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Research Institute of Exploration and Development PetroChina Southwest Oil&Gas Field CompanyChengdu610041SichuanChina Chemical and Petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCalgaryT2N 1N4Canada

With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration ***,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum *** it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the ***,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the *** this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained *** depth corresponding to a dry layer ratio of 100%is the *** on this,a quantitative prediction model for the DLOA was finally *** results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep *** critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the *** depth of the DLOA was 9,000 *** study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling.

关键词： Deep layer Tarim Basin Hydrocarbon accumulation Depth limit of oil accumulation Prediction model