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Pulmonary reversed halo cycles and consolidations after immunotherapy:A case report
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作者 Hong Suo Yu-Jie Shi +2 位作者 Zhao-Di Huang Kai Xu Hui Huang 《World Journal of Clinical Cases》 SCIE 2023年第28期6938-6942,共5页
BACKGROUND Immune checkpoint inhibitor-associated interstitial lung disease(ICI-ILD)and opportunistic pneumonias are the main pulmonary complications during immunotherapy for malignancies.The organizing pneumonia(OP)p... BACKGROUND Immune checkpoint inhibitor-associated interstitial lung disease(ICI-ILD)and opportunistic pneumonias are the main pulmonary complications during immunotherapy for malignancies.The organizing pneumonia(OP)pattern is one of the common radiological manifestations of ICI-ILD,and OP is the most common cause of reversed halo cycles and consolidations.However,opportunistic pneumonias should be excluded.CASE SUMMARY In this report,we described a case of a 44-year-old man with esophageal cancer who showed multiple reversed-halo cycles and consolidations on chest computed tomography(CT)after he had a cold during immunotherapy.He was diagnosed with esophageal squamous-cell cancer(T2NIM0)after surgery.Then,he was successfully treated with 6 cycles of chemotherapy plus tislelizumab,one cycle of radiotherapy and 9 cycles of tislelizumab.Two months later,he complained of low-grade fever and cough with nonpurulent sputum after he had a cold.Community-acquired pneumonia was considered,but moxifloxacin was ineffective.Chest CT showed multiple reversed-halo cycles and consolidations.Mycobacterium tuberculosis was identified with next-generation sequence analysis of bronchoalveolar lavage fluid(BALF).Two months later,he improved with standard anti-tuberculosis medications.Both the cycles and consolidations disappeared in the repeat CT after 6 mo of medications.CONCLUSION When chest CT shows reversed-halo cycles and consolidations in patients during anticancer immunotherapy,both ICI-ILD and infectious pneumonia should be considered.BALF microbiological analysis was helpful to differentiate them. 展开更多
关键词 Reversed halo cycles consolidations IMMUNOTHERAPY TUBERCULOSIS Checkpoint inhibitor associated interstitial lung disease Case report
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Consolidation of high replacement ratio stone column-reinforced ground:Analytical solutions incorporating clogging effect
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作者 Jinxin Sun Mengmeng Lu +1 位作者 Baolong Xu Jie Shan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3311-3326,共16页
The utilization of stone columns has emerged as a popular ground improvement strategy,whereas the drainage performance can be adversely hampered by clogging effect.Despite the ample progress of calculation methods for... The utilization of stone columns has emerged as a popular ground improvement strategy,whereas the drainage performance can be adversely hampered by clogging effect.Despite the ample progress of calculation methods for the consolidation of stone column-improved ground,theoretical investigations into the clogging effect have not been thoroughly explored.Furthermore,it is imperative to involve the column consolidation deformation to mitigate computational error on the consolidation of composite ground with high replacement ratios.In this context,an analytical model accounting for the initial clogging and coupled time and depth-dependent clogging of stone columns is established.Then,the resulting governing equations and analytical solutions are obtained under a new flow continuity relationship to incorporate column consolidation deformation.The accuracy and reliability of the proposed model are illustrated by degradation analysis and case studies with good agreements.Subsequently,the computed results of the current study are juxtaposed against the existing models,and an in-depth assessment of the impacts of several crucial parameters on the consolidation behavior is conducted.The results reveal that ignoring column consolidation deformation leads to an overestimate of the consolidation rate,with maximum error reaching up to 16%as the replacement ratio increases.Furthermore,the initial clogging also has a significant influence on the consolidation performance.Additionally,the increment of depth and time-clogging factors a and b will induce a noticeable retardation of the consolidation process,particularly in the later stage. 展开更多
关键词 consolidATION Composite ground Stone column Clogging effect Ground improvement Analytical model
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Urban Freight Consolidation Model for Post-Hauler Planning
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作者 Mohammad Anwar Rahman 《Journal of Transportation Technologies》 2024年第2期255-272,共18页
Freight transportation in urban areas has increased significantly in a shorter period due to the widespread use of e-commerce, fast delivery, and population growth. Recently, a noticeable government initiative aimed a... Freight transportation in urban areas has increased significantly in a shorter period due to the widespread use of e-commerce, fast delivery, and population growth. Recently, a noticeable government initiative aimed at creating an effective, acceptable, and sustainable city logistics policy. This paper examines freight consolidation as a transportation strategy for optimizing last-mile delivery costs. Freight consolidation involves combining smaller shipments from various origins into a single, larger shipment for more efficient transportation to a common destination. This approach is particularly beneficial for last-mile delivery, where frequent deliveries of smaller quantities are frequently visible. Finally, we provide an illustrative example targeting urban freight stakeholders for practicing possible consolidation methodology. The result in the illustrative example shows that freight with 3-day consolidation, despite the delay penalty, is cheaper than daily shipping, and both are cheaper than 2-day consolidated shipping. The study will benefit urban businesses and freight services. 展开更多
关键词 Freight consolidation Urban Transport Intermodal Last-Mile Delivery
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Effect of particle composition and consolidation degree on the wave-induced liquefaction of soil beds
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作者 Zhiyuan Chen Yupeng Ren +1 位作者 Guohui Xu Meng Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期11-22,共12页
The wave-induced liquefaction of seabed is responsible for causing damage to marine structures.Particle composition and consolidation degree are the key factors affecting the pore water pressure response and liquefact... The wave-induced liquefaction of seabed is responsible for causing damage to marine structures.Particle composition and consolidation degree are the key factors affecting the pore water pressure response and liquefaction behavior of the seabed under wave action.The present study conducted wave flume experiments on silt and silty fine sand beds with varying particle compositions.Furthermore,a comprehensive analysis of the differences and underlying reasons for liquefaction behavior in two different types of soil was conducted from both macroscopic and microscopic perspectives.The experimental results indicate that the silt bed necessitates a lower wave load intensity to attain the liquefaction state in comparison to the silty fine sand bed.Additionally,the duration and development depth of liquefaction are greater in the silt bed.The dissimilarity in liquefaction behavior between the two types of soil can be attributed to the variation in their permeability and plastic deformation capacity.The permeability coefficient and compression modulus of silt are lower than those of silty fine sand.Consequently,silt is more prone to the accumulation of pore pressure and subsequent liquefaction under external loading.Prior research has demonstrated that silt beds with varying consolidation degrees exhibit distinct initial failure modes.Specifically,a dense bed undergoes shear failure,whereas a loose bed experiences initial liquefaction failure.This study utilized discrete element simulation to examine the microscopic mechanisms that underlie this phenomenon. 展开更多
关键词 wave flume LIQUEFACTION pore water pressure consolidation permeability experiment discrete element simulation
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Shape Analysis of Agricultural Parcels for Land Consolidation Priorities in Tekirdag Province,Turkey
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作者 Bahadir ALTURK 《Chinese Geographical Science》 SCIE CSCD 2024年第1期93-105,共13页
Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significan... Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significantly to spatial prioritization where there is also a high probability of achieving positive effects of consolidation projects.This study aims to determine the shape degree of the agricultural parcels both at singular and rural county scales in Tekirdag Province,Turkey in 2020 by combining the parcel shape index(PSI) with the minimum bounding geometry index(MBG) to improve parcel scores.Hot-spot zones of the highly irregular and near optimum parcels were also determined using Getis-Ord G_(i)^(*) statistic.The parcel degrees were classified into four categories,namely highly irregular,irregular,regular and near optimum.The obtained unweighted scores of the parameters exhibit deviations from the expected values.After weighting by pairwise comparison,the values approached ideal scores.Among 346 740 parcels,53% were highly irregular and irregular and 47% were regular and near optimum shapes after weighting whereas these were 70% and 30%,respectively before weighting.The average parcel degree of 63 rural counties was regular while the average parcel degree of the remaining 264 rural counties was irregular.The combined use of PSI and MBG index improved the correctness of the parcel shape score.It could be suggested to use as a tool in land consolidation prioritization. 展开更多
关键词 land consolidation priority parcel shape index(PSI) minimum bounding geometry(MBG) sustainable rural development hot-spot analysis Tekirdag Province TURKEY
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Spatiotemporal variations in ecosystem services and their trade-offs and synergies against the background of the gully control and land consolidation project on the Loess Plateau,China
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作者 WANG Jing WEI Yulu +2 位作者 PENG Biao LIU Siqi LI Jianfeng 《Journal of Arid Land》 SCIE CSCD 2024年第1期131-145,共15页
Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implicatio... Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River Basin.Therefore,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.We also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological environment.The results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,respectively.The ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were significant.The GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more significant.This study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and ecological security. 展开更多
关键词 ecosystem services trade-offs and synergies gully control and land consolidation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model Loess Plateau
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Physical model investigation on effects of drainage condition and cement addition on consolidation behavior of tailings slurry within backfilled stopes 被引量:2
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作者 Qinghai Ma Guangsheng Liu +1 位作者 Xiaocong Yang Lijie Guo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第8期1490-1501,共12页
Estimation of stressses within the tailings slurry during self-weight consolidation is a critical issue for cost-effective barricade design and efficient backfill planning in underground mine stopes.This process requi... Estimation of stressses within the tailings slurry during self-weight consolidation is a critical issue for cost-effective barricade design and efficient backfill planning in underground mine stopes.This process requires a good understanding of self-weight consolidation behaviors of the tailings slurry within practical stopes,where many factors can have significant effects on the consolidation,including drainage condition and cement addition.In this paper,the prepared tailings slurry with different cement contents(0,4.76wt%,and 6.25wt%)was poured into1.2 m-high columns,which allowed three drainage scenarios(undrained,partial lateral drainage near the bottom part,and full lateral drainage boundaries)to investigate the effects of drainage condition and cement addition on the consolidation behavior of the tailings slurry.The consolidation behavior was analyzed in terms of pore water pressure(PWP),settlement,volume of drainage water,and residual water content.The results indicate that increasing the length of the drainage boundary or cement content aids in PWP dissipation.In addition,constructing an efficient drainage boundary was more favorable to PWP dissipation than increasing cement addition.The final stable PWP on the column floor was not sensitive to cement addition.The final settlement of uncemented tailings slurry was independent of drainage conditions,and that of cemented tailings slurry decreased with the increase in cement addition.Notably,more pore water can drain out from the cemented tailings slurry than the uncemented tailings slurry during consolidation. 展开更多
关键词 tailings backfill consolidATION slurry drainage cement content physical model test
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Premature Boarding and Human Capital Accumulation for Rural Pupils: Evidence from School Consolidations
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作者 侯海波 吴要武 宋映泉 《China Economist》 2020年第2期92-108,共17页
From 2001 to 2012,many local governments in China closed down village teaching sites for primary school students in the first and second grades,consolidating them into larger township schools more distant from village... From 2001 to 2012,many local governments in China closed down village teaching sites for primary school students in the first and second grades,consolidating them into larger township schools more distant from village students’homes.School closure and consolidation are particularly striking in China’s central and western regions,where swathes of rural labor migrated to cities for jobs.As a result,numerous primary school pupils are forced to study at boarding schools in the first and second grades,which is considered as too early for pupils to live without parental care.This paper employs survey data from 137 township schools with boarding qualifications collected by a project team consisting of researchers from the China Institute for Educational Finance Research(CIEFR)of Peking University,the Institute of Population and Labor Economics of the Chinese Academy of Social Sciences(IPLE-CASS)and the Capital University of Economics and Business(CUEB).By matching the home-school distance with village teaching site information as the proxy variable for the school consolidation policy,this paper evaluates the policy's impact on the likelyhood of premature boarding for primary school pupils,as well as the impact on their human capital accumulation.Our study finds that the creation of teaching sites makes it less likely for primary school pupils to board at school.Premature boarding impedes children’s human capital accumulation,and the harmful effect is particularly striking for children lacking pastoral teachers,raised by grandparents and from families above average income levels,as well as girls. 展开更多
关键词 school consolidation primary school students premature boarding instrumental variable human capital
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Meningeal T-cells in the cross-talk between memory consolidation and sleep
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作者 Rodrigo Pacheco Valentina Ugalde 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2687-2688,共2页
Some years ago,the infiltration of T-cells into the central nervous system(CNS) was considered a pathological condition exclusively.However,during the last two decades,a growing body of studies has shown that T-cells ... Some years ago,the infiltration of T-cells into the central nervous system(CNS) was considered a pathological condition exclusively.However,during the last two decades,a growing body of studies has shown that T-cells are essential players regulating several physiological processes exerted by the CNS,including stress resilience,social behavior. 展开更多
关键词 behavior. SLEEP consolidATION
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Virtual Machine Consolidation with Multi-Step Prediction and Affinity-Aware Technique for Energy-Efficient Cloud Data Centers
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作者 Pingping Li Jiuxin Cao 《Computers, Materials & Continua》 SCIE EI 2023年第7期81-105,共25页
Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,... Virtual machine(VM)consolidation is an effective way to improve resource utilization and reduce energy consumption in cloud data centers.Most existing studies have considered VM consolidation as a bin-packing problem,but the current schemes commonly ignore the long-term relationship between VMs and hosts.In addition,there is a lack of long-term consideration for resource optimization in the VM consolidation,which results in unnecessary VM migration and increased energy consumption.To address these limitations,a VM consolidation method based on multi-step prediction and affinity-aware technique for energy-efficient cloud data centers(MPaAF-VMC)is proposed.The proposed method uses an improved linear regression prediction algorithm to predict the next-moment resource utilization of hosts and VMs,and obtains the stage demand of resources in the future period through multi-step prediction,which is realized by iterative prediction.Then,based on the multi-step prediction,an affinity model between the VM and host is designed using the first-order correlation coefficient and Euclidean distance.During the VM consolidation,the affinity value is used to select the migration VM and placement host.The proposed method is compared with the existing consolidation algorithms on the PlanetLab and Google cluster real workload data using the CloudSim simulation platform.Experimental results show that the proposed method can achieve significant improvement in reducing energy consumption,VM migration costs,and service level agreement(SLA)violations. 展开更多
关键词 Cloud computing VM consolidation multi-step prediction affinity relationship energy efficiency
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Strength Model of Soda Residue Soil Considering Consolidation Stress and Structural Influence
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作者 GONG Xiaolong WANG Yuanzhan CHEN Tong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1216-1226,共11页
Soda residue(SR)is a type of industrial waste produced in the soda process with the ammonia-soda method.Applying SR to backfilling solves the land occupation and environmental pollution problems in coastal areas and s... Soda residue(SR)is a type of industrial waste produced in the soda process with the ammonia-soda method.Applying SR to backfilling solves the land occupation and environmental pollution problems in coastal areas and saves material costs for foundation engineering.The strength characteristics of soda residue soil(SRS)under different consolidation conditions are the key points to be solved in the engineering application of SRS.Triaxial compression tests were performed on the undisturbed SRS of Tianjin Port.The shear properties of SRS under different consolidation conditions were then discussed.Meanwhile,a structural strength model(SSM)based on Mohr-Coulomb theory was proposed.SSM reflects the influence of soil structure on undrained strength(Cu)and divides the Cu into the following two parts:friction strength(C_(uf))and original structural strength(C_(u0)).C_(uf)characterizes the magnitude of friction between soil particles,which is related to the consolidation stress.Meanwhile,C_(u0)represents the structural effect on soil strength,which is related to the soil deposition and consolidation processes.SSM was validated by the test data of undisturbed soils.Results reveal that the undisturbed soil generally had a certain C_(u0).Therefore,the SRS strength model was established by combining the experimental law of SRS with SSM.Error analysis shows that the SRS strength model can effectively predict the Cu of undisturbed SRS in Tianjin Port under different consolidation conditions. 展开更多
关键词 soda residue soil triaxial test strength model soil structure consolidation stress
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Triaxial tension and compression tests on saturated lime-treated plastic clay upon consolidated undrained conditions
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作者 Kuchvichea Kan Bertrand François 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3328-3342,共15页
Lime-treatment of clayey soil significantly increases its shear and tensile strengths.Consequently,the tensile strength of lime-treated soils deserves careful investigation because it may provide an appreciable benefi... Lime-treatment of clayey soil significantly increases its shear and tensile strengths.Consequently,the tensile strength of lime-treated soils deserves careful investigation because it may provide an appreciable benefit for the stability of earth structures.This study investigates the tensile and shear strengths of an untreated and lime-treated(3%of lime)plastic clay at different curing times(7 d,56 d and 300 d),through triaxial tension and compression tests.Triaxial tension tests are performed using“diabolo-shaped”soil samples with reduced central section,such that the central part of the specimen can be under axial tension while both end-sections remain in axial compression.Consolidated undrained(CU)conditions with measurement of pore water pressure allow analyzing the failure conditions through effective stress and total stress approaches.The results of triaxial tension tests reveal that the failure occurs under tensile mode at low confining pressure while extensional shear failure mode is observed under higher confining pressure.Consequently,a classical Mohr-Coulomb shear failure criterion must be combined with a cut-off tensile strength criterion that is not affected by the confining pressure.When comparing shear failure under compression and tension,a slight anisotropy is observed. 展开更多
关键词 Tensile strength consolidated undrained(CU)triaxial test Lime-treated soils Failure criterion
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An Experimental Study on the Reinforcement of Weakly-Consolidated Shallow Formation in Deep Water Using an Epoxy Resin-Based Fluid
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作者 Leiju Tian Yuhuan Bu +1 位作者 Huajie Liu Lingyun Zhao 《Fluid Dynamics & Materials Processing》 EI 2023年第5期1215-1226,共12页
The mechanical properties of Portland cement differ from the weakly consolidated shallow formation in deep water.This results in undesired abrupt changes in the compressive strength and elastic modulus at the cement–... The mechanical properties of Portland cement differ from the weakly consolidated shallow formation in deep water.This results in undesired abrupt changes in the compressive strength and elastic modulus at the cement–formation interface.In this study,a water-borne epoxy resin was applied as a strengthening material to reinforce the weakly consolidated shallow formation and protect the cement sheath from potential failure.The mechanical properties of the unconsolidated clay were tested,including their changes with increases in the temperature and curing time.In addition,the effects of the seawater,cement slurry alkaline filtrate,and saltwater drilling fluid were evaluated.As confirmed by the results,the strengthening fluid was excellent at reinforcing the unconsolidated clay,with a compressive strength of 2.49 MPa(after curing for 7 days),even at a dosage of 5%.A cement slurry filtrate with a high pH was suitable to produce the required strengthening of the formation,especially its early age strength.It should also be pointed out that the used fluid exhibited good compatibility with the saltwater drilling fluid and seawater behaved well as a diluent for the strengthening fluid. 展开更多
关键词 MANUSCRIPT compressive strength deepwater oil and gas well well cementing epoxy resin weakly consolidated shallow formation
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Exploration on the Path of Whole-region Comprehensive Land Consolidation under the Background of Rural Revitalization
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作者 Xueli CAI Shiqin YANG 《Asian Agricultural Research》 2023年第6期1-6,共6页
Based on the specific concept of whole-region comprehensive land consolidation and the development history of land consolidation in China,the internal relationship between rural revitalization strategy and whole-regio... Based on the specific concept of whole-region comprehensive land consolidation and the development history of land consolidation in China,the internal relationship between rural revitalization strategy and whole-region comprehensive land consolidation is clarified from the perspective of historical development,and the problems faced by whole-region comprehensive land consolidation,such as rural"hollowing out",weak linkage between execution departments and neglect of ecological restoration,are deeply analyzed.Furthermore,some new paths for whole-region land consolidation are put forward,such as strengthening the top-level system design,handling the relationship between stock and increment,evaluating the potential of rural land consolidation,coordinating the win-win cooperation between middle-level executive departments,encouraging the innovation at the bottom and enhancing the comprehensive management of ecological environment. 展开更多
关键词 Rural revitalization Whole-region comprehensive land consolidation Path EXPLORATION
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Two-dimensional plane strain consolidation of unsaturated soils considering the depth-dependent stress
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作者 Lei Wang Sidong Shen +2 位作者 Tianyi Li Minjie Wen Annan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1603-1614,共12页
In practical engineering,the total vertical stress in the soil layer is not constant due to stress diffusion,and varies with time and depth.Therefore,the purpose of this paper is to investigate the effect of stress di... In practical engineering,the total vertical stress in the soil layer is not constant due to stress diffusion,and varies with time and depth.Therefore,the purpose of this paper is to investigate the effect of stress diffusion on the two-dimensional(2D)plane strain consolidation properties of unsaturated soils when the stress varies with time and depth.A series of semi-analytical solutions in terms of excess pore air and water pressures and settlement for 2D plane strain consolidation of unsaturated soils can be derived with the joint use of Laplace transform and Fourier sine series expansion.Then,the inverse Laplace transform of the semi-analytical solution is given in the time domain using a self-programmed code based on Crump’s method.The reliability of the obtained solutions is proved by the degeneration.Finally,the 2D plots of excess pore pressures and the curves of settlement varying with time,considering different physical parameters of unsaturated soil stratum and depth-dependent stress,are depicted and analyzed to study the 2D plane strain consolidation properties of unsaturated soils subjected to the depthdependent stress. 展开更多
关键词 Semi-analytical solutions Two-dimensional(2D)plane strain consolidATION Unsaturated soils Depth-dependent stress Laplace transform
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耐高温泡沫树脂低伤害均匀固砂技术
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作者 匡韶华 吕民 +1 位作者 孙振宇 胡祎 《油田化学》 CAS CSCD 北大核心 2024年第1期53-60,共8页
针对常规泡沫树脂体系耐温性较差和辽河油田疏松砂岩稠油油藏化学固砂储层伤害大与有效期短的问题,以环氧树脂、酚醛树脂、疏水纳米SiO_(2)、硅烷偶联剂等为原料制得纳米改性树脂基液,然后加入固化剂、乳化剂、起泡剂、稳泡剂等添加剂... 针对常规泡沫树脂体系耐温性较差和辽河油田疏松砂岩稠油油藏化学固砂储层伤害大与有效期短的问题,以环氧树脂、酚醛树脂、疏水纳米SiO_(2)、硅烷偶联剂等为原料制得纳米改性树脂基液,然后加入固化剂、乳化剂、起泡剂、稳泡剂等添加剂制得泡沫树脂固砂体系。评价了该体系的固化温度、固砂强度、渗透性能、耐温性能和非均质多层注入性能;研发了配套的泡沫发生器,形成了耐高温泡沫树脂低伤害均匀固砂技术,并在辽河油田进行了现场应用。结果表明,泡沫树脂固砂体系的最优配方为:20%~30%树脂基液+8%~12%酚醛胺类固化剂+0.3%乳化剂OP-10+0.5%起泡剂有机硅表面活性剂+0.1%固体稳泡剂纳米SiO_(2)+0.1%聚合物稳泡剂聚乙二醇+57%~71%清水。该体系的起泡体积约为发泡前的7倍、半衰期大于20 min,可在35℃以上固化,固化后耐温可达280℃,既具有低温固化的特点,又具有耐高温的特点。在不同温度下固化的泡沫树脂固结岩心的抗压强度达到5 MPa以上,固砂强度高,满足疏松砂岩固砂强度的要求。对用0.25~0.42 mm石英砂制得的固结岩心的固砂渗透率达到4.8μm2,优于常规树脂固砂剂(1.9μm~2)。在非均质多油层中可明显防止高渗透层突进,改善固砂剂注入剖面,实现均匀固砂。现场试验取得良好的防砂效果,验证了该技术可实现均匀固砂和低伤害特性。利用泡沫树脂流体特性实现非均质多油层均匀固砂,达到了提高化学固砂效果和防砂有效期的目的。 展开更多
关键词 化学固砂 泡沫树脂 低温固化 耐高温 均匀固砂 泡沫发生器 辽河油田
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海陆交互相软土固结抗剪强度指标变化规律研究
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作者 刘红军 何程铃 +2 位作者 陈锋 周志军 杨超 《森林工程》 北大核心 2024年第4期218-224,共7页
以珠三角地区海陆交互相淤泥质软土为研究对象,通过室内直剪试验探究不同固结压力和固结度下抗剪强度及抗剪强度指标的变化规律,提出抗剪强度及对应指标-固结度-固结压力三维Logistic数学模型。研究结果表明,当固结压力P≥200 kPa、固结... 以珠三角地区海陆交互相淤泥质软土为研究对象,通过室内直剪试验探究不同固结压力和固结度下抗剪强度及抗剪强度指标的变化规律,提出抗剪强度及对应指标-固结度-固结压力三维Logistic数学模型。研究结果表明,当固结压力P≥200 kPa、固结度U≥40%时,软土黏聚力(c)和内摩擦角(φ)增长较为明显;当U=100%时,各级固结压力作用下的软土抗剪强度(τ)相较于初始状态分别提高了7.89、12.73、13.50、18.20、22.38 kPa;所给出的三维数学模型可直接计算出某一固结压力和固结度下的抗剪强度指标c、φ、τ。研究成果能够更为准确地评价该地区软土地基逐级加载过程中的整体稳定性。 展开更多
关键词 海陆交互相软土 分级加载 抗剪强度指标 固结度 固结压力
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学术期刊“铸牢中华民族共同体意识”栏目设置路径研究 被引量:1
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作者 韩芳 刘子豪 《阴山学刊》 2024年第1期16-21,47,共7页
铸牢中华民族共同体意识是新时代党的民族工作的主线,是民族地区各项工作的主线,也是学术研究的重要内容之一。学术界有必要对这一理论进行全方位、深层次的解读。学术期刊作为学术理论发表的窗口,有义务、有责任创办好“铸牢中华民族... 铸牢中华民族共同体意识是新时代党的民族工作的主线,是民族地区各项工作的主线,也是学术研究的重要内容之一。学术界有必要对这一理论进行全方位、深层次的解读。学术期刊作为学术理论发表的窗口,有义务、有责任创办好“铸牢中华民族共同体意识”栏目,以推动学术理论的创新和发展,同时提高学术期刊的学术质量和学术品位。学术期刊在设置“铸牢中华民族共同体意识”栏目时,应做到求同存异,与中华文明相融合;因地制宜,与地方文化相融合;百家争鸣,与栏目建设相融合;捕捉热点,与时事新闻相融合;广泛约稿,与编辑专业相融合。 展开更多
关键词 铸牢中华民族共同体意识 学术期刊 栏目设置
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基于滑移线法的黏土海床中浅基础固结承载力分析
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作者 李志坚 廖晨聪 +1 位作者 张璐璐 叶冠林 《上海交通大学学报》 EI CAS CSCD 北大核心 2024年第7期1047-1056,共10页
为评估海底浅基础服役过程的承载力时变规律,推导了预载作用下黏土海床完全固结后的不排水抗剪强度分布,利用滑移线法给出了应力特征线方程并求解出浅基础固结承载力,研究了预载比、土体不均匀性、有效内摩擦角和基础尺寸对浅基础固结... 为评估海底浅基础服役过程的承载力时变规律,推导了预载作用下黏土海床完全固结后的不排水抗剪强度分布,利用滑移线法给出了应力特征线方程并求解出浅基础固结承载力,研究了预载比、土体不均匀性、有效内摩擦角和基础尺寸对浅基础固结承载力的影响.结果表明:浅基础固结承载力的相对增长幅度和预载比近似呈线性关系,由土体不均匀因子和有效内摩擦角共同决定,不受基础尺寸的影响.通过与水土耦合有限元分析结果进行比较,对所提方法的准确性进行了严格的验证,表明了该方法的有效性.最后,根据有限元结果分析了滑移线解的误差来源,发现孔压计算差异是导致固结承载力预测结果产生误差的主要原因.该滑移线解可快速准确地预估浅基础固结承载力的增长规律,为海底浅基础的优化设计提供重要参考. 展开更多
关键词 黏土海床 浅基础 固结承载力 滑移线法 预载作用
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SHANSEP试验方法改进与验证
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作者 代云霞 郭晓勇 《中国港湾建设》 2024年第6期34-38,共5页
为满足工程实际需要,对SHANSEP试验方法加以改进,将淤泥固结至远大于其前期固结压力后,再逐级卸载以模拟超固结黏土,在不同的超固结比下进行了三轴固结不排水试验。试验表明:等向固结的三轴试验,也能较好地拟合出超固结土不排水强度与... 为满足工程实际需要,对SHANSEP试验方法加以改进,将淤泥固结至远大于其前期固结压力后,再逐级卸载以模拟超固结黏土,在不同的超固结比下进行了三轴固结不排水试验。试验表明:等向固结的三轴试验,也能较好地拟合出超固结土不排水强度与正常固结土强度、超固结比之间的关系式;提出了工程地区超固结土不排水强度公式,可推算不同超固结比下的土体强度;通过本次试验中对加荷方式的改进与拓宽,取代了原有k0固结或单剪仪的要求,提高了试验效率、节约成本,且该方法可推广使用到更多土类上,对研究超固结土的性质有一定工程实用意义。 展开更多
关键词 SHANSEP试验方法 不排水强度 等向固结 超固结比
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