期刊文献+
共找到1,324篇文章
< 1 2 67 >
每页显示 20 50 100
Cutting-edge Technological Innovation Outcome Displayed at 2024 Beijing Science and Technology Week
1
作者 Zhang Yida 《China's Foreign Trade》 2024年第3期47-49,共3页
The 2024 National Science and Technology Week and Beijing Science and Technology Week opened in Shougang Park in Shijingshan District from May 25 to June 1.Under the theme of“Carrying forward the spirit of scientists... The 2024 National Science and Technology Week and Beijing Science and Technology Week opened in Shougang Park in Shijingshan District from May 25 to June 1.Under the theme of“Carrying forward the spirit of scientists and inspiring societal innovation,”this event focused on the new-generation IT technology,medical health,energy and technology,modern agriculture and intelligent manufacturing industries. 展开更多
关键词 DISTRICT cutTING opened
下载PDF
Market capitalization shock effects on open innovation models in e‑commerce:golden cut q‑rung orthopair fuzzy multicriteria decision‑making analysis
2
作者 Nikita Moiseev Alexey Mikhaylov +1 位作者 Hasan Dinçer Serhat Yüksel 《Financial Innovation》 2023年第1期1476-1500,共25页
This research paper analyzes revenue trends in e-commerce,a sector with an annual sales volume of more than 340 billion dollars.The article evaluates,despite a scarcity of data,the effects on e-commerce development of... This research paper analyzes revenue trends in e-commerce,a sector with an annual sales volume of more than 340 billion dollars.The article evaluates,despite a scarcity of data,the effects on e-commerce development of the ubiquitous lockdowns and restriction measures introduced by most countries during the pandemic period.The analysis covers monthly data from January 1996 to February 2021.The research paper analyzes relative changes in the original time series through the autocorrelation function.The objects of this analysis are Amazon and Alibaba,as they are benchmarks in the e-commerce industry.This paper tests the shock effect on the e-commerce companies Alibaba in China and Amazon in the USA,concluding that it is weaker for companies with small market capitalizations.As a result,the effect on estimated e-trade volume in the USA was approximately 35%in 2020.Another evaluation considers fuzzy decision-making methodology.For this purpose,balanced scorecard-based open financial innovation models for the e-commerce industry are weighted with multistepwise weight assessment ratio analysis based on q-rung orthopair fuzzy sets and the golden cut.Within this framework,a detailed analysis of competitors should be made.The paper proves that this situation positively affects the development of successful financial innovation models for the e-commerce industry.Therefore,it may be possible to attract greater attention from e-commerce companies for these financial innovation products. 展开更多
关键词 E-COMMERCE Golden cut open innovation Sustainable trade
下载PDF
A comparison of the energy consumption and carbon emissions for different modes of transportation in open-cut coal mines 被引量:13
3
作者 Liu Fuming Cai Qingxiang +1 位作者 Chen Shuzhao Zhou Wei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第2期261-266,共6页
Transportation accounts for 80% of open-cut coal mine carbon emissions.With regard to the energy consumption and carbon emissions of transportation within an open-cut mine,this paper systematically compared the work a... Transportation accounts for 80% of open-cut coal mine carbon emissions.With regard to the energy consumption and carbon emissions of transportation within an open-cut mine,this paper systematically compared the work and energy consumption of a truck and belt conveyor on a theoretical basis,and constructed a model to calculate the energy consumption of open-cut mine transportation.Life cycle carbon emission factors and power consumption calculation model were established through a Process Analysis–Life Cycle Analysis(PA–LCA).The following results were obtained:(1) the energy consumption of truck transportation was four to twelve times higher than that of the belt conveyor;(2) the CO2 emissions from truck transportation were three to ten times higher than those of the belt conveyor;(3) with the increase in the slope angle for transportation,the ratio of truck to belt conveyor for both energy consumption and carbon emissions gradually decreased;(4) based on 2013 prices in China,the energy cost of transportation using a belt conveyor in open-cut coal mines could save 0.6–2.4 Yuan/(t km) compared to truck transportation. 展开更多
关键词 二氧化碳排放量 能源消耗 交通运输 煤矿 明挖 矿用带式输送机 生命周期分析 卡车运输
下载PDF
基坑装配式内支撑高脚螺栓-模袋混凝土固支端及其承载性能
4
作者 单余含 张明聚 +4 位作者 郭彩霞 郭飞 李鹏飞 高云昊 刘文杰 《铁道标准设计》 北大核心 2024年第6期161-170,共10页
基坑工程内支撑体系中,混凝土支撑因其承载能力高、布置不受限制、端部节点现浇、整体性良好等优势得以在基坑工程中广泛使用,但混凝土支撑在设计与施工中的弊病也十分显著,存在设计截面过大、施工周期长、污染性强、成本高、浪费严重... 基坑工程内支撑体系中,混凝土支撑因其承载能力高、布置不受限制、端部节点现浇、整体性良好等优势得以在基坑工程中广泛使用,但混凝土支撑在设计与施工中的弊病也十分显著,存在设计截面过大、施工周期长、污染性强、成本高、浪费严重等问题。因而,针对混凝土支撑在基坑工程中表现出的优势与劣势,并结合地铁明挖车站深基坑工程的特点,设计一种装配式组合钢管混凝土内支撑,从提高端部节点刚度和强度、实现端部固定连接等角度出发,提出一种适应于地铁基坑装配式组合钢管混凝土内支撑的高脚螺栓-模袋混凝土固支端。通过阐明固支端的设计方案、构造特点和工作原理,并将其与混凝土支撑现浇节点进行对比分析,论证了由预埋钢板、空心法兰盘、模袋混凝土和高脚螺栓等特殊构件组成的固支端,在支撑体系中发挥了固定支座的作用;为建立固支端设计与验算的理论依据,通过分析固支端的力学机理、破坏模式及其演变规律,得到固支端的抗压与抗弯承载力的解析方法;为验证固支端承载性能的理论解析方法的可行性,结合数值模拟验证分析了理论与数值结果,并对影响固支端承载性能的主要因素进行参数化分析。 展开更多
关键词 地铁 明挖车站 深基坑工程 装配式组合钢管混凝土内支撑 固支端 模袋混凝土 承载性能
下载PDF
OPTIMIZATION OF CUT-OFF GRADE IN OPEN-PIT BASED ON CONTROL THEORY
5
作者 Xie YingliangDepartment of Management,  South Institute of Metallurgy, Ganzhou 341000, P. R. China 《中国有色金属学会会刊:英文版》 CSCD 1998年第2期178-181,共4页
OPTIMIZATIONOFCUTOFFGRADEINOPENPITBASEDONCONTROLTHEORY①XieYingliangDepartmentofManagement,SouthInstituteof... OPTIMIZATIONOFCUTOFFGRADEINOPENPITBASEDONCONTROLTHEORY①XieYingliangDepartmentofManagement,SouthInstituteofMetalurgy,Ganzhou... 展开更多
关键词 cutoff GRADE openpit control theory
下载PDF
Variable Stars in the 50BiN Open Cluster Survey.Ⅲ.NGC 884
6
作者 Lin-Hong Wang Qian-Heng Nie +5 位作者 Kun Wang Xiao-Dian Chen Chun-Guang Zhang Li-Cai Deng Xiao-Bin Zhang Tian-Lu Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期36-45,共10页
Open clusters are the basic building blocks that serve as a laboratory for the study of young stellar populations in the Milky Way.Variable stars in open clusters provide a unique way to accurately probe the internal ... Open clusters are the basic building blocks that serve as a laboratory for the study of young stellar populations in the Milky Way.Variable stars in open clusters provide a unique way to accurately probe the internal structure,temporal and dynamical evolutionary stages of individual stars and the host cluster.The most powerful tool for such studies is time-domain photometric observations.This paper follows the route of our previous work,concentrating on a photometric search for variable stars in NGC 884.The target cluster is the companion of NGC869,forming the well-known double cluster system that is gravitationally bound.From the observation run in 2016 November,a total of 9247 B-band CCD images and 8218Ⅴ-band CCD images were obtained.We detected a total of 15 stars with variability in visual brightness,including five Be stars,three eclipsing binaries,and seven of unknown types.Two new variable stars were discovered in this work.We also compared the variable star content of NGC 884 with its companion NGC 869. 展开更多
关键词 STARS VARIABLES general-(Galaxy:)open clusters and associations individual(… …)-(stars:)binaries GENERAL
下载PDF
Fatigue Behavior of Open-Holed CFRP Laminates with Initially Cut Fibers
7
作者 Sudarsono Sudarsono Keiji Ogi 《Open Journal of Composite Materials》 2017年第1期49-62,共14页
Carbon fiber-reinforced plastic (CFRP) laminates with initially cut fibers (ICFs) have good formability without large degradation of static strength;however, their fatigue behavior has not been investigated thus far. ... Carbon fiber-reinforced plastic (CFRP) laminates with initially cut fibers (ICFs) have good formability without large degradation of static strength;however, their fatigue behavior has not been investigated thus far. In this paper, we investigated fatigue behavior and damage progress of open-holed CFRP laminates with ICFs having interlayers. Three types of CFRP laminates were employed: a laminate without ICF fabricated using an autoclave (Continuous-A), a laminate with ICF fabricated using an autoclave (ICF-A) and a laminate with ICF fabricated using press molding (ICF-P). First, fatigue test was conducted to obtain S (maximum stress)-N (the number of cycles to failure) curves in order to reveal fatigue strength. The fatigue tests for several specimens were interrupted at three prescribed numbers of cycles to observe damage progress. It is found that the Continuous-A laminate shows little strength degradation in the S-N curve while fatigue strength in both ICF laminates is decreased by approximately 30% at N of 106. In contrast, the damage progress of the ICF-P laminate is the least among the three laminates while the delamination progress at both edges and around the hole in the Continuous-A laminate is the most prominent. 展开更多
关键词 Carbon Fiber-Reinforced Plastic FATIGUE Initially cut Fibers open-Holed INTERLAYER
下载PDF
Groundwater impact of open cut coal mine and an assessment methodology:A case study in NSW 被引量:5
8
作者 Zhao Liang Ting Ren Wang Ningbo 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第5期861-866,共6页
Large scale open cut coal mining operations have significant impacts to groundwater in surrounding areas in both active and post-mining phases. The prediction of water inflows into a surface mine excavation is one of ... Large scale open cut coal mining operations have significant impacts to groundwater in surrounding areas in both active and post-mining phases. The prediction of water inflows into a surface mine excavation is one of the many components involved in mine design phase. Groundwater performance also reacts to mining activities from the operational, economic and safety implications perspective. Under NSW planning legislation, as part of the comprehensive risk assessment, a groundwater impact assessment has to be conducted for a coal project to predict and mitigate the impacts in consideration of the government requirements. In this paper, the groundwater assessment modelling of mine pits was discussed in predicting of groundwater inflows and reviewing analytical and numerical approaches. A methodology of groundwater impact assessment for an open cut mine in NSW with a three-dimensional groundwater flow model Modflow Surfact demonstrated its functions in simulating the project's impacts on the groundwater regime. The key findings with mitigations are discussed and recommended in the paper to reduce impacts on groundwater and fulfil regulation requirements in NSW. 展开更多
关键词 open cut coal MINE GROUNDWATER impact assessment Mining exposure area GROUNDWATER modelling methodology
下载PDF
Risk management in open cut coal mines 被引量:3
9
作者 Ismet Canbulat John Hoelle Jason Emery 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期369-374,共6页
There are a number of geotechnical systems used at open cut operations of Anglo American's Metallurgical Coal business unit in Australia. These systems are mainly mine site specific, based on geological informatio... There are a number of geotechnical systems used at open cut operations of Anglo American's Metallurgical Coal business unit in Australia. These systems are mainly mine site specific, based on geological information and used as hazard plans. They are qualitative and reliant upon the experienced judgement of site based engineers and the general workforce. They are not suitable for calculating the associated risks of geological structures and mining responses. A uniform risk rating system that can be used to provide an unbiased, standard and quantifiable assessment of the risk from highwall and lowwall failures is therefore developed using the experience gained with such systems in Anglo American's South African operations. This system is a semi-quantitative risk rating system and takes into account the relative differences in the importance of hazards as experienced at each mine site as a result of different combinations of geotechnical factors and mining conditions. It is based on critical geotechnical and other parameters that have been identified by site mining engineers, geologists and geotechnical engineers. The primary advantage of this risk rating system is that all open cut mines in the Anglo American's Metallurgical Coal operations use a near identical system, which enables the user to compare the risk after each blast and with other mines. The system can be adjusted to meet local mine specific requirements. The implementation of this system, a computer program that automatically calculates the risks and recommends predetermined controls, has been made as practical and as easy to use as possible. This program can be used by personnel from other mining disciplines not directly related to geotechnical engineering. 展开更多
关键词 Geotechnical openRisk Semi-quantitative Risk management open cut Ground control
下载PDF
Process for improving the ladle free- opening rate for high aluminum steel in continuous casting 被引量:3
10
作者 LIU Junzhan ZHOU Tongjun LUO Hui 《Baosteel Technical Research》 CAS 2015年第1期42-45,共4页
Steel 20Mn23AlV is a type of high aluminum steel with a very low ladle free-opening rate. The aluminum composition of 20Mn23AlV ranges from 1.6% to 2.45% ,which is significantly higher than other types of steel. Accor... Steel 20Mn23AlV is a type of high aluminum steel with a very low ladle free-opening rate. The aluminum composition of 20Mn23AlV ranges from 1.6% to 2.45% ,which is significantly higher than other types of steel. According to the real condition of 40 t ladle in steel-making plant of Baosteel Special Steel Company, previous works show that the key factors affecting the ladle free-opening rate of high aluminum steel in continuous casting are:sand material, accessories baking, ladle nozzle cleaning, the process and amount of adding sand, and the rate of argon stirring during refining. Therefore, improving the ladle filler sand quality, baking all of the raw materials, controlling the addition of ladle filler sand, cleaning the ladle nozzle, and optimizing argon stirring during the refining process can resolve the problem of a low ladle free-opening rate of high aluminum steel caused by the long ladle time of liquid steel. 展开更多
关键词 continuous casting high aluminum steel LADLE free - opening rate
下载PDF
Layer regrouping for water-flooded commingled reservoirs at a high water-cut stage 被引量:2
11
作者 Chuan-Zhi Cui Jian-Peng Xu +3 位作者 Duan-Ping Wang Zhi-Hong Liu Ying-song Huang Zheng-Ling Geng 《Petroleum Science》 SCIE CAS CSCD 2016年第2期272-279,共8页
Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to impro... Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to improve oil recovery for high water-cut multilayered reservoirs. Dif- ferent regroup scenarios may lead to different production performances. Based on unstable oil-water flow theory, a multilayer commingled reservoir simulator is established by modifying the production split method. Taking into account the differences of layer properties, including per- meability, oil viscosity, and remaining oil saturation, the pseudo flow resistance contrast is proposed to serve as a characteristic index of layer regrouping for high water-cut multilayered reservoirs. The production indices of multi- layered reservoirs with different pseudo flow resistances are predicted with the established model in which the data are taken from the Shengtuo Oilfield. Simulation results show that the pseudo flow resistance contrast should be less than 4 when the layer regrouping is implemented. The K-means clustering method, which is based on the objec- tive function, is used to automatically carry out the layer regrouping process according to pseudo flow resistances. The research result is applied to the IV-VI sand groups of the second member of the Shahejie Formation in the Shengtuo Oilfield, a favorable development performance is obtained, and the oil recovery is enhanced by 6.08 %. 展开更多
关键词 Water-flooded reservoirs Layer regrouping.Flow resistance - High water cut Reservoir simulation
下载PDF
桩-墙叠合全预制装配明挖地铁隧道建造方案及工程应用 被引量:1
12
作者 符瑞安 李兆平 +2 位作者 周健 马绍麟 黄明利 《铁道标准设计》 北大核心 2023年第6期140-147,共8页
明挖法施工的装配式地铁隧道基坑围护桩通常为现场浇注混凝土桩,且只作为基坑开挖阶段的挡土结构,不将其作为侧墙永久结构的一部分,这种结构设计方法偏于保守,导致资源浪费。为此,提出桩-墙叠合全预制装配明挖地铁隧道建造方案,其主要... 明挖法施工的装配式地铁隧道基坑围护桩通常为现场浇注混凝土桩,且只作为基坑开挖阶段的挡土结构,不将其作为侧墙永久结构的一部分,这种结构设计方法偏于保守,导致资源浪费。为此,提出桩-墙叠合全预制装配明挖地铁隧道建造方案,其主要特点是:基坑围护桩和隧道结构均采用预制结构且叠合布置,围护桩既是基坑开挖期间的临时挡土结构,同时也是隧道侧墙永久结构的一部分。以济南市济阳有轨电车明挖区间隧道工程为背景,开展围护桩和隧道侧墙叠合方案的比选。基于不同叠合方案结构受力分析和叠合施工方便性的综合考虑,提出在围护桩和隧道侧墙四角点进行叠合连接的措施;详细讨论了“桩-墙叠合方案、基坑预制围护桩布置、隧道主体结构装配分块、桩-墙叠合连接方法”;最后结合本工程试验段的施工,阐述了桩-墙叠合明挖隧道装配施工的关键工序及解决措施。 展开更多
关键词 地铁隧道 明挖法 预制围护桩 预制隧道结构 -墙叠合方案 关键工序
下载PDF
New open cluster candidates discovered in the XSTPS-GAC survey
13
作者 Jin-Cheng Guo Hua-Wei Zhang +12 位作者 Hui-Hua Zhang Xiao-Wei Liu Hai-Bo Yuan Yang Huang Song Wang Li Chen Hai-Bin Zhao Ji-Feng Liu Bing-Qiu Chen Mao-Sheng Xiang Zhi-Jia Tian Zhi-Ying Huo Chun Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第3期77-90,共14页
The Xuyi Schmidt Telescope Photometric Survey of the Galactic Anti-center(XSTPS-GAC)is a photometric sky survey that covers nearly 6000 deg^2 towards the Galactic Anti-center(GAC) in the g,r,i bands. Half of its s... The Xuyi Schmidt Telescope Photometric Survey of the Galactic Anti-center(XSTPS-GAC)is a photometric sky survey that covers nearly 6000 deg^2 towards the Galactic Anti-center(GAC) in the g,r,i bands. Half of its survey field is located on the Galactic Anti-center disk,which makes XSTPSGAC highly suitable to search for new open clusters in the GAC region. In this paper,we report new open cluster candidates discovered in this survey,as well as properties of these open cluster candidates,such as age,distance and reddening,derived by isochrone fitting in the color-magnitude diagram(CMD).These open cluster candidates are stellar density peaks detected in the star density maps by applying the method from Koposov et al. Each candidate is inspected in terms of its true color image composed from three XSTPS-GAC band images. Then its CMD is checked,in order to identify whether the central region stars have a clear isochrone-like trend differing from background stars. The parameters derived from isochrone fitting for these candidates are mainly based on three band photometry of XSTPS-GAC.Moreover,when these new candidates are able to be seen clearly in 2 MASS data,their parameters are also derived based on the 2 MASS(J-H,J) CMD. There are a total of 320 known open clusters rediscovered and 24 new open cluster candidates discovered in this work. Furthermore,the parameters of these new candidates,as well as another 11 previously known open clusters,are properly determined for the first time. 展开更多
关键词 open clusters and associations general - Galaxy structure - methods data analysis
下载PDF
A Study on Modifying the Calculation Model of Valid Opening Size of Heat-bonded Nonwoven Fabrics
14
作者 余序芬 吴美萍 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期52-56,共5页
It has been found that there are marked errors in the value of valid opening size of heat-bonded nonwoven fabrics between theoretical calculations and engineering measurements. A new modified theoretical model is adva... It has been found that there are marked errors in the value of valid opening size of heat-bonded nonwoven fabrics between theoretical calculations and engineering measurements. A new modified theoretical model is advanced in this paper. The equivalent diameter of the pore of a fibre web is used to calculate the valid opening size instead of the maximum diameter of inscribed circle used, because the fibres in practical fibre webs are flexible elastomers with definite diameters and the pore of fibre web may produce deformation in screening teat and engineering usage. The results show that the theoretical calculations coincide well with the engineering measurements. This method offers a theoretical basis for computer simulation to the performance of filters of heatbonded nonwoven fabrics. 展开更多
关键词 HEAT - bonded NONWOVEN fabrics theoretical MODEL VALID openING SIZE MODEL modification .
下载PDF
An application of the KNND method for detecting nearby open clusters based on Gaia-DR1
15
作者 Xin-Hua Gao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第6期89-94,共6页
This paper presents a preliminary test of the k-th nearest neighbor distance (KNND) method for detecting nearby open clusters based on Gaia-DR1. We select 38 386 nearby stars (〈 100 pc) from the Gaia-DR1 catalog,... This paper presents a preliminary test of the k-th nearest neighbor distance (KNND) method for detecting nearby open clusters based on Gaia-DR1. We select 38 386 nearby stars (〈 100 pc) from the Gaia-DR1 catalog, and then use the KNND method to detect overdense regions in three-dimensional space. We find two overdense regions (the Hyades and Coma Berenices (Coma Ber) open clusters), and obtain 57 reliable cluster members. Based on these cluster members, the distances to the Hyades and Coma Ber clusters are determined to be 46.0±0.2 and 83.5±0.3 pc, respectively. Our results demonstrate that the KNND method can be used to detect open clusters based on a large volume of astrometry data. 展开更多
关键词 open clusters and associations individual (Hyades Coma Ber) - astrometry- parallaxes- stars distances
下载PDF
Preliminary Study on Water Demand Law of 1-0 Rooted Cuttings of Populus szechuanica
16
作者 Dabuqiong Haoyu WANG +2 位作者 Huanhuan XIE Zhen XING Yanhui YE 《Meteorological and Environmental Research》 CAS 2021年第4期39-42,共4页
In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and ... In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and the law of water demand of P.szechuanica was grasped.In this paper,potted seedlings of 1-0 rooted cuttings of P.szechuanica were taken as research objects,and change situation of water consumption under different water control gradients was measured regularly by using weighing method,further analyzing dynamic change of water consumption of P.szechuanica and revealing water demand law of 1-0 rooted cuttings of P.szechuanica.The results showed that total change of water consumption of 1-0 rooted cuttings of P.szechuanica had"slow-fast-slow-fast"double-peak trend in the growth period of the current year,and corresponded with univariate linear relation(R^(2)=0.7137),with significant difference.In whole growth period,water consumption in August was the highest,which was 2.7 times of that in June and July and 1.5 times of that after September.In different water control treatments,the dynamic changes of daily and monthly water consumption were significantly different.In seven water control treatments,monthly water consumption was between(6315.95±1690.70)and(10105.28±3065.30)g/month,and mean was(8211.07±2308.23)g/month.With intensification of water control treatment,water consumption increased,but there was no seedling death due to water shortage.P.szechuanica has great plasticity in water demand,and can survive in both arid and humid environments.Meanwhile,it is revealed that P.szechuanica is the most widely distributed tree species in the region. 展开更多
关键词 Populus szechuanica 1-0 rooted cuttings Water consumption Water demand law
下载PDF
Physiological Dynamics and Transcriptomic Analysis of Cut Roses‘Carola’Treated with KNO_(3)
17
作者 Songmei Liu Yuheng Wu +4 位作者 Hongmei Li Dongli Cai Huiling Liang Changchun Ye Shenggen He 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第12期3267-3290,共24页
The consumption of cut roses(Rosa hybrida)has always ranked first in the world.However,it is vulnerable to rapid petal and leaf wilting due to leaf stomatal water loss,which seriously affects its ornamental quality an... The consumption of cut roses(Rosa hybrida)has always ranked first in the world.However,it is vulnerable to rapid petal and leaf wilting due to leaf stomatal water loss,which seriously affects its ornamental quality and economic value.Stomatal movement,a key in plant physiological processes,is influenced by potassium and nitrate.Advancing comprehension of its physiological and molecular mechanism holds promise for preserving the freshness of cut roses.This study observed the impacts of different concentrations of KNO_(3) vase treatments on stomatal opening and water loss in cut rose‘Carola’leaves,as well as their transcriptional responses to KNO_(3).Water loss rates were influenced by KNO_(3) concentrations,with the 25 and 75 mmol/L treatments exhibiting the highest water loss rates.The stomatal aperture reached its widest value when treated with 75 mmol/L KNO_(3).Transcriptional sequencing analysis was performed to identify differentially expressed genes(DEGs)of which 5456 were up-regulated,and 6607 were down-regulated associated with photosynthesis,starch and sucrose metabolism,metabolic pathways,plant-pathogen interaction,plant hormone signal transduction,and related pathways.246 DEGs were selected related to response to KNO_(3) treatment,of which gene ontology(GO)enrichment were nitrate and terpenoid metabolism,ion transport,and response to stimuli.Further heatmap analysis revealed that several genes related to nitrate transport a metabolism,K+transport,vacuoles,and aquaporin were in close association with the response to KNO_(3) treatment.Weighted gene co-expression network analysis(WGCNA)revealed that hub genes,including LAX2,TSJT1,and SCPL34 were identified in turquoise,black,and darkgreen module.Transcription factors such as NAC021,CDF3,ERF053,ETR2,and ARF6 exhibited regulatory roles in the response to KNO_(3) treatment under light conditions.These findings provide valuable insights into the physiological and molecular mechanisms underlying the response of cut rose leaves to KNO_(3) treatment. 展开更多
关键词 cut rose stomatal opening KNO_(3) TRANSCRIPTOME water loss
下载PDF
城市地下立交明挖隧道受力特性数值模拟分析--以重庆星光大道延伸段节点改造工程为例
18
作者 邹华 陈明 +1 位作者 刘建松 王承阳 《科技和产业》 2023年第8期226-230,共5页
为研究地下立交隧道结构在施工期间和后续运营过程中的受力变化,以重庆渝北金洲大道和星光大道延伸段节点改造工程为研究背景,采用ABAQUS数值模拟软件对该项目某复杂断面主线隧道衬砌结构在施工不同阶段的受力情况进行分析。结果表明,... 为研究地下立交隧道结构在施工期间和后续运营过程中的受力变化,以重庆渝北金洲大道和星光大道延伸段节点改造工程为研究背景,采用ABAQUS数值模拟软件对该项目某复杂断面主线隧道衬砌结构在施工不同阶段的受力情况进行分析。结果表明,基坑开挖后坑底有一定量的隆起,随着施工的进行,隆起量逐渐减小,主线隧道拱脚处存在应力集中现象,隧道的受力和变形主要受填土荷载的影响,上部匝道隧道施工对下部主线隧道的影响较小。基于数值模拟结果提出优化施工方案的建议,为类似明挖隧道工程施工提供参考。 展开更多
关键词 明挖隧道 地下立交 数值模拟 衬砌受力
下载PDF
分段管廊装载供水管道穿越地裂缝适宜性研究
19
作者 徐强 常曙光 +2 位作者 卢全中 彭建兵 刘聪 《地下空间与工程学报》 CSCD 北大核心 2024年第3期1026-1038,共13页
在活动地裂缝影响下,供水管道拉裂、错断现象时有发生,并引发严重的次生灾害。本文以西安市西南郊水厂拟建球墨铸铁管道穿越地裂缝为工程背景,建立管道45°穿越活动地裂缝的数值模型,分析地裂缝影响下管道的内力响应与变形特征,结... 在活动地裂缝影响下,供水管道拉裂、错断现象时有发生,并引发严重的次生灾害。本文以西安市西南郊水厂拟建球墨铸铁管道穿越地裂缝为工程背景,建立管道45°穿越活动地裂缝的数值模型,分析地裂缝影响下管道的内力响应与变形特征,结果表明:地裂缝作用会使管道接口偏转角过大而导致其防水失效。因此提出一种分段管廊装载供水管道穿越地裂缝的方法,建立分段管廊装载供水管道穿越地裂缝的数值模型,分析管道与管廊通缝、错缝两种工况、不同分段管廊长度、不同地裂缝位置、不同穿越角度下管廊与管道的内力响应与变形特征。得出管廊装载管道穿越地裂缝的最佳方案为管道与管廊通缝布设,采用单节长度为18 m的分段管廊,使地裂缝位于管廊的2/3处,并尽量以小角度穿越地裂缝。研究成果对城市供水管道穿越活动地裂缝的工程建设与灾害防治具有实际意义。 展开更多
关键词 供水管道 地裂缝 分段管廊 球墨铸铁 工程措施
下载PDF
公路明挖隧道近接穿越地铁高架桥跨段稳定性分析
20
作者 周伟 赵阳 刘毅 《工程建设与设计》 2024年第9期83-85,共3页
结合无锡至太仓高速公路惠山新城隧道工程穿越无锡地铁1号线高架桥工程设计,研究公路明挖隧道近接穿越地铁高架桥跨时对高架稳定性的影响,结合相关工程资料进行分析,在此基础上对基坑围护进行设计,并根据基坑所处地理位置及工程地质情况... 结合无锡至太仓高速公路惠山新城隧道工程穿越无锡地铁1号线高架桥工程设计,研究公路明挖隧道近接穿越地铁高架桥跨时对高架稳定性的影响,结合相关工程资料进行分析,在此基础上对基坑围护进行设计,并根据基坑所处地理位置及工程地质情况,利用Midas GTSNX建立三维模型进行模拟,分析其位移及整体稳定性。 展开更多
关键词 公路 明挖隧道 地铁高架桥 稳定性分析
下载PDF
上一页 1 2 67 下一页 到第
使用帮助 返回顶部