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Effect of LaCl_3 on Resistance and Absorptive Capacity to Formaldehyde of Indoor Ornamental Plants under Formaldehyde Stress
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作者 闫生荣 花海蓉 +1 位作者 杨春和 张跃群 《Agricultural Science & Technology》 CAS 2012年第12期2607-2609,共3页
[Objective] This study aimed to determine the effect of rare earth biological regulator LaCl3 on the absorptive capacity to formaldehyde of four indoor ornamental plants, and to screen out the plant whose absorptive c... [Objective] This study aimed to determine the effect of rare earth biological regulator LaCl3 on the absorptive capacity to formaldehyde of four indoor ornamental plants, and to screen out the plant whose absorptive capacity to formaldehyde can be increased most greatly by LaCl3. [Method] Effect of LaCl3 on absorptive capacity to formaldehyde of four indoor ornamental plants was studied through fumigating in laboratory. Simultaneously, the indoor ornamental plant, which could significantly en- hance the degradation capacity of formaldehyde, was screened out to study the physiological and biochemical mechanisms of formaldehyde resistance. [Result] The ability to absorb formaldehyde of four indoor ornamental plants was enhanced by dif- ferent ranges after spraying with LaCl3 at suitable concentrations. The ability to ab- sorb formaldehyde of Hedera nepalensis var. sinensis, Chlorophytum comosum, Scindapsus aureun and Sansevieria trifasciata increased by 15.16%, 4.72%, 19.75% and 7.68%, respectively. In the four indoor ornamental plants, the capacity of S. au- reun to absorb formaldehyde was greatly improved by spraying LaCl3. When S. au- reun was stressed by formaldehyde, its chlorophyll content decreased by 39.87%, membrane permeability, MDA accumulation and POD activity increased by 8.17%, 56.92%, and 11.32%, respectively. However, compared the pre-spraying group with the no-spraying group under formaldehyde stress, chlorophyll content of S. aureun reduced less, membrane permeability and MDA cumulative both increased less, but POD activity increased more. [Conclusion] The formaldehyde absorption capacity of S. aureun was mostly improved after LaCl3 was sprayed. 展开更多
关键词 La3+ Indoor ornamental plants Absorptive capacity to formaldehyde resistance
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Muscle capacity and physical function in older women:What are the impacts of resistance training? 被引量:1
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作者 Anne O.Brady Chad R.Straight 《Journal of Sport and Health Science》 SCIE 2014年第3期179-188,共10页
The number of older adults (individuals ≥65 years), particularly women, in our society is increasing and understanding the impact of exercise on muscle capacity (e.g., strength and power) and subsequently physica... The number of older adults (individuals ≥65 years), particularly women, in our society is increasing and understanding the impact of exercise on muscle capacity (e.g., strength and power) and subsequently physical function is of utmost importance to prevent disability and maintain independence. Muscle capacity declines with age and this change negatively impacts physical function in older women. Exercise, specifically resistance training, is recommended to counteract these declines; however, the synergistic relationships between exercise, muscle capacity, and physical function are poorly understood. This review will summarize the literature regarding age-related changes in the aforementioned variables and review the research on the impact of resistance training interventions on muscle capacity and physical function in older women. Recommendations for future research in this area will be discussed. 展开更多
关键词 Muscle capacity Older women Physical function resistance training
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Estimation of Axial Pile Bearing Capacity According to Shear Strength Parameters of Soil 被引量:1
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作者 Yu, XD Yan, SW Sun, WH 《China Ocean Engineering》 SCIE EI 1997年第2期235-242,共8页
At pesent, it is very popular to estimate pile bearing capacity by use of empirical formula and physical indexes of soil provided in the design codes for civil construction in China. This paper attempts to apply mecha... At pesent, it is very popular to estimate pile bearing capacity by use of empirical formula and physical indexes of soil provided in the design codes for civil construction in China. This paper attempts to apply mechanical indexes of soil and semi-empirical formulas, which are based on soil mechanical theories and were summarized and presented by Meyerhof in 1976, to calculate the axial pile bearing capacity. Loading test results of 24 single piles in Tianjin area have been collected and compared with the proposed calulation approach. 展开更多
关键词 axial pile bearing capacity consolidated-undrained shear strength index test pile skin resistance tip resistance
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Insulin resistance in H pylori infection and its association with oxidative stress 被引量:18
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作者 Mehmet Aslan Mehmet Horoz +5 位作者 Yasar Nazligul Cengiz Bolukbas F Fusun Bolukbas Sahbettin Selek Hakim Celik Ozcan Erel 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第42期6865-6868,共4页
AIM: To determine the insulin resistance (IR) and oxidative status in H pylori infection and to find out if there is any relationship between these parameters and insulin resistance. METHODS: Fifty-five H pylori posit... AIM: To determine the insulin resistance (IR) and oxidative status in H pylori infection and to find out if there is any relationship between these parameters and insulin resistance. METHODS: Fifty-five H pylori positive and 48 H pylori negative patients were enrolled. The homeostasis model assessment (HOMA) was used to assess insulin resistance. Serum total antioxidant capacity (TAC), total oxidant status (TOS) and oxidative stress index (OSI) were determined in all subjects. RESULTS: The total antioxidant capacity was significantly lower in H pylori positive group than in H pylori negative group (1.36 ± 0.33 and 1.70 ± 0.50, respectively; P < 0.001), while the total oxidant status and oxidative stress index were significantly higher in H pylori positive group than in H pylori negative group (6.79 ± 3.40 and 5.08 ± 0.95, and 5.42 ± 3.40 and 3.10 ± 0.92, respectively; P < 0.001). Insulin resistance was significantly higher in H pylori positive group than in H pylori negative group (6.92 ± 3.86 and 3.61 ± 1.67, res- pectively; P < 0.001). Insulin resistance was found to be significantly correlated with total antioxidant capacity (r = -0.251, P < 0.05), total oxidant status (r = 0.365, P < 0.05), and oxidative stress index (r = 0.267, P < 0.05). CONCLUSION: Insulin resistance seems to be associated with increased oxidative stress in H pylori infection. Further studies are needed to clarify the mechanisms underlying this association and elucidate the effectof adding antioxidant vitamins to H pylori eradication therapy on insulin resistance during H pylori infection. 展开更多
关键词 HPYLORI Insulin resistance Total antioxidant capacity Total oxidant status Oxidative stress index
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Alginate oligosaccharide improves resistance to postharvest decay and quality in kiwifruit(Actinidia deliciosa cv. Bruno) 被引量:9
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作者 Ruiling Zhuo Boqiang Li Shiping Tian 《Horticultural Plant Journal》 SCIE CSCD 2022年第1期44-52,共9页
Kiwifruit is an extremely perishable fruit;postharvest disease and senescence during storage can reduce the fruit quality,resulting in economic loss.Considerable research effort has focused on identifying safe and cos... Kiwifruit is an extremely perishable fruit;postharvest disease and senescence during storage can reduce the fruit quality,resulting in economic loss.Considerable research effort has focused on identifying safe and cost-effective ways to preserve fresh kiwifruit.To this end,the present study investigated the effects of alginate oligosaccharide(AOS)soaking treatment on postharvest quality and disease in the‘Bruno’variety of kiwifruit.The involved physiological mechanisms were further explored.The results showed that AOS did not inhibit the growth of Botrytis cinerea in vitro,the causal agent of gray mold in kiwifruit,but reduced the incidence of gray mold and diameter of lesions of kiwifruit during storage.Kiwifruit treated with 50 mg·L-1 AOS showed a higher degree of firmness and lower soluble solid content than control fruit treated with distilled water.Moreover,AOS treatment inhibited the activity of polygalacturonase and pectinesterase,while enhancing the activity of polyphenoloxidase,l-phenylalanine ammonia lyase andβ-1,3-glucanase related to pathogen defense,and also improved total antioxidant capacity determined by the DPPH,FRAP,and ABTS methods in kiwifruit.These results indicate that 50 mg·L-1 AOS can confer disease resistance in kiwifruit during storage. 展开更多
关键词 Alginate oligosaccharide KIWIFRUIT Botrytis cinerea Antioxidant capacity Disease resistance
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Study of the Bearing Capacity at the Variable Cross-Section of A Riser- Surface Casing Composite Pile 被引量:2
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作者 LIU Run LIANG Chao 《China Ocean Engineering》 SCIE EI CSCD 2021年第2期262-271,共10页
Reducing the cost of offshore platform construction is an urgent issue for marginal oilfield development.The offshore oil well structure includes a riser and a surface casing.The riser,surface casing and oil well ceme... Reducing the cost of offshore platform construction is an urgent issue for marginal oilfield development.The offshore oil well structure includes a riser and a surface casing.The riser,surface casing and oil well cement can be considered special variable cross-section piles.Replacing or partially replacing the steel pipe pile foundation with a variable cross-section pile to provide the required bearing capacity for an offshore oil platform can reduce the cost of foundation construction and improve the economic efficiency of production.In this paper,the finite element analysis method is used to investigate the variable cross-section bearing mode of composite piles composed of a riser and a surface casing in saturated clay under a vertical load.The calculation formula of the bearing capacity at the variable section is derived based on the theory of spherical cavity expansion,the influencing factors of the bearing capacity coefficient N_(c) are revealed,and the calculation method of N_(c) is proposed.By comparing the calculation results with the results of the centrifuge test,the accuracy and applicability of the calculation method are verified.The results show that the riser composite pile has a rigid core in the soil under the variable cross-section,which increases the bearing capacity at the variable cross-section. 展开更多
关键词 riser-surface casing composite pile variable cross-section bearing capacity coefficient pile end resistance soil rigid core
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Bending Resistance of Steel Plate-Reinforced Concrete Beam 被引量:1
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作者 TIAN Zhimin CHEN Jie 《Transactions of Tianjin University》 EI CAS 2006年第B09期210-213,共4页
The formulas for calculating bending-resistant capacity of a steel plate-reinforced concrete composite beam are derived. To validate the formulas, experiments of the composite beam under three-point bending are carrie... The formulas for calculating bending-resistant capacity of a steel plate-reinforced concrete composite beam are derived. To validate the formulas, experiments of the composite beam under three-point bending are carried out. Calculated results based on the formulas are in good agreement with experimental results. 展开更多
关键词 steel plate-reinforced concrete bending resistance capacity FORMULA EXPERIMENT
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Seismic Liquefaction Resistance Based on Strain Energy Concept Considering Fine Content Value Effect and Performance Parametric Sensitivity Analysis 被引量:1
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作者 Nima Pirhadi Xusheng Wan +3 位作者 Jianguo Lu Jilei Hu Mahmood Ahmad Farzaneh Tahmoorian 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期733-754,共22页
Liquefaction is one of the most destructive phenomena caused by earthquakes,which has been studied in the issues of potential,triggering and hazard analysis.The strain energy approach is a common method to investigate... Liquefaction is one of the most destructive phenomena caused by earthquakes,which has been studied in the issues of potential,triggering and hazard analysis.The strain energy approach is a common method to investigate liquefaction potential.In this study,two Artificial Neural Network(ANN)models were developed to estimate the liquefaction resistance of sandy soil based on the capacity strain energy concept(W)by using laboratory test data.A large database was collected from the literature.One group of the dataset was utilized for validating the process in order to prevent overtraining the presented model.To investigate the complex influence of fine content(FC)on liquefaction resistance,according to previous studies,the second database was arranged by samples with FC of less than 28%and was used to train the second ANN model.Then,two presented ANN models in this study,in addition to four extra available models,were applied to an additional 20 new samples for comparing their results to show the capability and accuracy of the presented models herein.Furthermore,a parametric sensitivity analysis was performed through Monte Carlo Simulation(MCS)to evaluate the effects of parameters and their uncertainties on the liquefaction resistance of soils.According to the results,the developed models provide a higher accuracy prediction performance than the previously publishedmodels.The sensitivity analysis illustrated that the uncertainties of grading parameters significantly affect the liquefaction resistance of soils. 展开更多
关键词 Liquefaction resistance capacity strain energy artificial neural network sensitivity analysis Monte Carlo Simulation
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Prediction of future capacity and internal resistance of Li-ion cells from one cycle of input data 被引量:2
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作者 Calum Strange Gonçalo dos Reis 《Energy and AI》 2021年第3期209-216,共8页
There is a large demand for models able to predict the future capacity retention and internal resistance(IR)of Lithium-ion battery cells with as little testing as possible.We provide a data-centric model accurately pr... There is a large demand for models able to predict the future capacity retention and internal resistance(IR)of Lithium-ion battery cells with as little testing as possible.We provide a data-centric model accurately predicting a cell’s entire capacity and IR trajectory from one single cycle of input data.This represents a significant reduction in the amount of input data needed over previous works.Our approach characterises the capacity and IR curve through a small number of key points,which,once predicted and interpolated,describe the full curve.With this approach the remaining useful life is predicted with an 8.6%mean absolute percentage error when the input-cycle is within the first 100 cycles. 展开更多
关键词 capacity degradation Internal resistance degradation Prediction of full degradation curve Knee and elbow-points Lithium-ion cells Machine learning Remaining useful life
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Resistivity and thermal infrared precursors associated with cemented backfill mass 被引量:5
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作者 XU Wen-bin 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2329-2335,共7页
The stability of cemented backfill mass is important to keep miners and equipment safe in underground backfill miming.The stress-strain behavior, resistivity and thermal infrared(TIR) characteristics of backfill mass ... The stability of cemented backfill mass is important to keep miners and equipment safe in underground backfill miming.The stress-strain behavior, resistivity and thermal infrared(TIR) characteristics of backfill mass under uniaxial compression were investigated. The monitoring system consisted of a TIR observation system, a stress-strain monitoring system and a resistivity measurement system. Precursory information for impending failure of cemented backfill mass was collected, including TIR, strain and resistivity precursors. The sensitivity and difference of different monitoring information to the same failure event were compared.The results show that the time-space evolution process of the resistivity and TIR is basically the same as the whole process from compression deformation to failure of backfill mass, and the time variation of resistivity and TIR is obviously characterized by stage.The resistivity precursor turns out earlier than the TIR and the strain. The resistivity relation with loading compression is anti-symmetry, decreasing as the compression stress increases before the peak strength of backfill mass. However, when the backfill mass enters into the phase of failure, the resistivity starts to increase as the stress increases. The change of the resistivity growth direction can be regarded as the resistivity-caution-point for the failure of backfill mass under uniaxial compression. It is also indicated that the TIR information mainly represents the surface temperature evolution in the process of compression before the backfill enters into the plastic-yield state. It can be a valuable tool to obtain the precursors for failure of cemented backfill mass for backfill mines. 展开更多
关键词 cemented backfill mass thermal infrared characteristic RESISTIVITY uniaxial compression
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Snow resisting capacity of Caragana microphylla and Achnatherum splendens in a typical steppe region of Inner Mongolia,China 被引量:2
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作者 YAN Min ZUO Hejun +2 位作者 WANG Haibing DONG Zhi LI Gangtie 《Journal of Arid Land》 SCIE CSCD 2020年第2期294-302,共9页
Snow resisting capacity of vegetation is important for secondary distribution of water resources in seasonal snow areas of grassland because it affects the regeneration,growth and nutrient circulation of vegetation in... Snow resisting capacity of vegetation is important for secondary distribution of water resources in seasonal snow areas of grassland because it affects the regeneration,growth and nutrient circulation of vegetation in grassland.This study investigated vegetation characteristics(canopy height,canopy length and crown width)of Caragana microphylla Lam.(shrub)and Achnatherum splendens(Trin.)Nevski.(herb),and snow morphologies(snow depth,snow width and snow braid length)in a typical steppe region of Inner Mongolia,China in 2017.And the influence of vegetation characteristic on snow resisting capacity(the indices of bottom area of snow and snow volume reflect snow resisting capacity)was analyzed.The results showed that snow morphology depends on vegetation characteristics of shrub and herb.The canopy height was found to have the greatest influence on snow depth and the crown width had the greatest influence on snow width.The canopy length was found to have little influence on morphological parameters of snow.When the windward areas of C.microphylla and A.splendens were within the ranges of 0.0-0.5 m2 and 0.0-8.0 m2,respectively,the variation of snow cover was large;however,beyond these areas,the variation of snow cover became gradually stable.The potential area of snow retardation for a single plant was 1.5-2.5 m2 and the amount of snow resistance was 0.15-0.20 m3.The bottom area of snow and snow volume(i.e.,snow resisting capacity)of clumped C.microphylla and A.splendens was found to be 4 and 25 times that of individual plant,respectively.The results could provide a theoretical basis both for the estimation of snow cover and the establishment of a plant-based technical system for the control of windblown snow in the typical steppe region of Inner Mongolia. 展开更多
关键词 HERB SHRUB SNOW COVER SNOW resisting capacity field observation STEPPE
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Early-age Electrical Resistivity and Reactive Capacity of Mineral Admixtures in Mortars 被引量:1
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作者 梁文泉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第4期158-162,共5页
A non-contacting electrical resistivity measurement device was used to investigate the effect of different types and contents of mineral admixtures on the hydration perfrormanee of mortars during early age. The experi... A non-contacting electrical resistivity measurement device was used to investigate the effect of different types and contents of mineral admixtures on the hydration perfrormanee of mortars during early age. The experimental results show that the changes of measured resistivity with time of hydration can be used to describe the hydration characteristics of cement-based materials, as well as the physical and chemical behavior of fly ash; blast furnace slag and silica fume at the very early ages. With an increasing replacement ratio of mineral admixtures, for the specimens blended with fly ash or slag, the resistivity increases firstly, then the following flatting period extends and after setting the resistivity increasing becomes slow and consequently a lower resistivity value at 24 hours occurs. This is due to the dilution effect and lower pozzolanicl hydraulic activity of fly ash and slag. However, for the samples incorporated with silica fume, the resistivity value through 24 hours is lower with shorter flatting period and larger slope in the resistivity curves, which is because of its particle size effect and higher pozzolanic activity of silica fume. Moreover, non-contacting resistivity measurement might provide a helpful information to predict the long term performanee including the durability of cement-based materials at early ages. 展开更多
关键词 mineral admixtures pozzalanic capacity early age electrical resistivity cementbased composites
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Upper Bound Solution of the Resisting Moment Bearing Capacity of A Composite Bucket Shallow Foundation of An Offshore Wind Turbine in Sand 被引量:1
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作者 LIU Run LI Tian-liang +1 位作者 CHEN Guang-si LIAN Ji-jian 《China Ocean Engineering》 SCIE EI CSCD 2022年第6期859-870,共12页
Bearing the large moment that is generated by the wind load that acts on the upper structure of offshore wind turbines is an important feature of their foundations that is different from other offshore structures.A co... Bearing the large moment that is generated by the wind load that acts on the upper structure of offshore wind turbines is an important feature of their foundations that is different from other offshore structures.A composite bucket shallow foundation(CBSF)has been proposed by Tianjin University to address the soft geological conditions in the offshore regions of China for wind turbines.The CBSF is a new type of foundation and is effective against large moments.The soil deformation test of a CBSF and the numerical simulation study under the same working conditions are carried out to determine the failure mechanism of a CBSF under moment loading.The resisting soil compression rateηm is defined as a new empirical parameter that indicates the ability of the soil inside the bucket to resist moment loading.The upper limit of the resisting moment bearing capacity of the bucket foundation is derived through the upper bound theorem of classical plasticity theory based on the failure mechanism.The calculation method is validated by tests of bucket models with different height-diameter ratios in sand under moment loading. 展开更多
关键词 bucket foundation failure mechanism resisting moment bearing capacity upper bound theorem resisting soil compression rate
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A One Health approach to fight antimicrobial resistance in Uganda: Implementation experience, results, and lessons learned
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作者 Reuben Kiggundu J.P.Waswa +12 位作者 Niranjan Konduri Hassan Kasuja Marion Murungi Patrick Vudriko Harriet Akello Eric Lugada Cecilia Muiva Esther Were Dinah Tjipura Henry Kajumbula Kate Kikule Emmanuel Nfor Mohan P.Joshi 《Biosafety and Health》 CAS CSCD 2024年第2期125-132,共8页
Uganda has been implementing the Global Health Security Agenda(GHSA)since 2015 to build its capacity according to World Health Organization(WHO)Benchmarks on International Health Regulations Capacities.The country rem... Uganda has been implementing the Global Health Security Agenda(GHSA)since 2015 to build its capacity according to World Health Organization(WHO)Benchmarks on International Health Regulations Capacities.The country remains prone to outbreaks,with more than 20 disease outbreaks reported in the past five years,including Ebola virus disease,Crimean-Congo haemorrhagic fever,Marburg haemorrhagic fever,measles,yellow fever,coronavirus disease 2019(COVID-19),and cholera.Antimicrobial resistance(AMR)is an ongoing challenge.Uganda scored capacity level 3 on infection prevention and control(IPC)and antimicrobial stewardship(AMS)in the 2017 Joint External Evaluation(JEE)assessment.Identified gaps were being addressed after a self-assessment in 2021.This paper describes the technical assistance approaches provided to Uganda by the Medicines,Technologies,and Pharmaceutical Services Program,funded by the United States(U.S.)Agency for International Development,and implemented by Management Sciences for Health.The program,through a One Health approach,supported systematic capacity strengthening based on the JEE's capacity advancement framework for global health security,specifically relating to AMR.The program's interventions impacted 32 WHO benchmark actions(7 for AMR multisectoral coordination,16 for IPC,and 9 for AMS),contributing to Uganda's strengthened GHSA capacity.Leveraging success built on the AMR platform,the program trained 745 health workers in IPC for the Ebola virus and provided support for simulation exercises by eight district IPC teams.The program also worked with the Ministry of Health to coordinate IPC for the COVID-19 response in five health regions,covering 45 districts and reaching 5,452 health workers at 858 health facilities. 展开更多
关键词 One health Antimicrobial resistance Antibiotic resistance Jointexternal evaluation Global health security Uganda AFRICA WHO Benchmarks for International Health Regulations Capacities
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Elasto-Plastic Test of Q235 Steel Bending Beam With Cracking Resistance 被引量:4
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作者 WANG Li-min FENG Ying +2 位作者 CHEN Fan-xiu WANG Hai-ying WANG Dong-xu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2013年第11期57-66,共10页
More than 30 bending beams with rectangular cross-section and different thicknesses and heights were pre- pared from Q295 steel. The specimen dimensions were about 240 mm (length) × 60 mm (height) ×70 mm... More than 30 bending beams with rectangular cross-section and different thicknesses and heights were pre- pared from Q295 steel. The specimen dimensions were about 240 mm (length) × 60 mm (height) ×70 mm (thick ness). Flaws were cut along its middle line with a wire cutter, with lengths ranging from 6 to 35 mm. Each specimen was tested with three-point bend loading, and a process curve was obtained between load and the displacement of the loading point, in order to analyze the fracture process when opening the crack. A deformation near the prefabricated crack was observed in the testing period, and the variation of the fracture characteristic parameters was analyzed for different sizes. For a comprehensive understanding of carbon steel fracture resistance behavior, its elasticity and plas- ticity were established by determining its Young's modulus and Poisson's ratio with an optical strain gauge. This gauge was also used for the loading process test. It was found that the fracture toughness varied with the dimensions, and the toughness of the elastic limit loading was almost constant. Using the relationship of crack resistance stress intensity factor and fracture criterion, the bearing capacity of the material structure could be estimated, which shows a good agreement with the experimental test data. 展开更多
关键词 elasto-plastic property fracture toughness elastic limit loading bearing capacity cracking resistance Q235 steel bending beam
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Multifaceted Bioinspiration for Improving the Shaft Resistance of Deep Foundations 被引量:2
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作者 Seyed Ali Aleali Paola Bandini Craig Michael Newtson 《Journal of Bionic Engineering》 SCIE EI CSCD 2020年第5期1059-1074,共16页
This paper describes the bioinspiration process to derive design concepts for new deep foundation systems that have greater axial capacity per unit volume of pile material compared to conventional deep foundations.The... This paper describes the bioinspiration process to derive design concepts for new deep foundation systems that have greater axial capacity per unit volume of pile material compared to conventional deep foundations.The study led to bioinspired ideas that provide greater load capacity by increasing the pile shaft resistance.The bioinspiration approach used problem-solving strategies to define the problem and transfer strategies from biology to geotechnical engineering.The bioinspiration considered the load transfer mechanism of hydroskeletons and the anchorage of the earthworm,razor clam,kelp,and lateral roots of plants.The biostrategies that were transferred to the engineering domain included a flexible but incompressible core,passive behaviour against external loading,a longitudinally split shell that allows expansion for anchorage,and lateral root-type or setae-type anchoring elements.The concepts of three bioinspired deep foundation systems were proposed and described.The advantage of this approach was illustrated with two examples of the new laterally expansive pile in drained sand under axial compression.The finite element analysis of these examples showed that the new laterally expansive pile can provide considerably greater load capacity compared to a conventional cylindrical pile due to the increased lateral confining pressure developed along the expanded pile core. 展开更多
关键词 bioinspiration EXPANSION ANCHORAGE deep foundation pile capacity frictional resistance
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Redox-stress response resistance(RRR)mediated by hyperoxidation of peroxiredoxin 2 in senescent cells 被引量:1
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作者 Jiao Meng Yuanyuan Wang +4 位作者 Zhenyu Lv Xinhua Qiao Aojun Ye Qiaoli Zhu Chang Chen 《Science China(Life Sciences)》 SCIE CAS CSCD 2023年第10期2280-2294,共15页
Aging is closely related to redox regulation.In our previous work,we proposed a new concept,“redox-stress response capacity(RRC),”and found that the decline in RRC was a dynamic characteristic of aging.However,the m... Aging is closely related to redox regulation.In our previous work,we proposed a new concept,“redox-stress response capacity(RRC),”and found that the decline in RRC was a dynamic characteristic of aging.However,the mechanism of RRC decline during aging remains unknown.In this study,using the senescent human fibroblast cell model and Caenorhabditis elegans model,we identified that peroxiredoxin 2(PRDX2),as a hydrogen peroxide(H_(2)O_(2))sensor,was involved in mediating RRC.PRDX2 knockdown led to a decline of RRC and accelerated senescence in fibroblasts and prdx-2 mutant C.elegans also showed decreased RRC.The mechanism study showed that the decreased sensor activity of PRDX2 was related to the increase in hyperoxidation of PRDX2 in senescent cells.Moreover,the level of PRDX2 hyperoxidation also increased in old C.elegans.Simultaneous overexpression of both PRDX2 and sulfiredoxin(SRX)rescued the reduced RRC and delayed senescence.The increase in PRDX2 hyperoxidation in senescent cells led to a decrease in its sensor activity,resulting in the decreased cellular response to H_(2)O_(2),which is similar to the mechanism of insulin resistance due to the lower insulin receptor sensitivity.Treatment of young cells with a high level of H_(2)O_(2)to induce a higher level of PRDX2-SO_(3) resulted in mimicking the RRC decline in senescent cells,which is also similar to a model of insulin resistance induced by high levels of insulin.All these results thrillingly indicate that there is an insulin-resistance-like phenomenon in senescent cells,we named it redox-stress response resistance,RRR.RRR in senescent cells is an important new discovery that explains RRC decline during aging and reveals the internal relationship between redox regulation and aging from a new perspective. 展开更多
关键词 peroxiredoxin 2(PRDX2) redox-stress response capacity(RRC) redox-stress response resistance(RRR) H_(2)O_(2)sensor redox relay aging oxidative stress
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Effects of inner sleeves on the inner frictional resistance of open-ended piles driven into sand
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作者 Janaka J. KUMARA Yoshiaki KIKUCHI +1 位作者 Takashi KURASHINA Takahiro YAJIMA 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2016年第4期499-505,共7页
In open-ended piles, inner friction is developed between inner pile shaf and the inner soil. Inner frictional resistance depends largely on the degree of soil plugging, which is influenced by many factors including pi... In open-ended piles, inner friction is developed between inner pile shaf and the inner soil. Inner frictional resistance depends largely on the degree of soil plugging, which is influenced by many factors including pile diameter, relative density and end conditions of piles. In this paper, effects of inner sleeves on inner frictional resistance are discussed. The experiments were conducted on a medium-dense sandy ground using laboratory-scale piles. It was observed that the piles penetrated under partially-plugged or unplugged state. The results suggest that inner fiictional resistance, Qin increases with sleeve height, l linearly and requires 2D (D is pile outer diameter) of l to produce a large as 50% of Qt by Qin (Qt is total resistance). The results also indicate that bearing capacity increases with wall thickness at the pile tip, which can be attributed to the increase in annular area. The results also indicate that soil plug height is independent of sleeve height. The results also reveal that the penetration of straight piles is closer to unplugged state than the sleeved piles. The results of incremental filling ratio and plug length ratio also indicate that the degree of soil plugging is affected by the sleeve height. 展开更多
关键词 bearing capacity inner frictional resistance inner sleeve open-ended piles soil plugging
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RESEARCH ON SYSTEM DYNAMICS MODEL OF CONVEYANCE CAPACITY IN SYMMETRIC COMPOUND CHANNELS 被引量:2
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作者 YANGKe-jun CAOShu-you LIUXing-nian 《Journal of Hydrodynamics》 SCIE EI CSCD 2005年第3期295-300,共6页
Stage-discharge curves are particularly important in river basin management. For a compound channel, the stage-discharge curve is often difficult to be extrapolated to yield estimates of level for a given frequency of... Stage-discharge curves are particularly important in river basin management. For a compound channel, the stage-discharge curve is often difficult to be extrapolated to yield estimates of level for a given frequency of flow. By analyzing a large number of experimental data from Science and Engineering Research Council Flood Channel Facility (SERC-FCF) and applying system dynamics method, the authors established system dynamics model of conveyance capacity when rivers flow in an overbank mode, spilling onto the adjoining flood plain. The model was applied to a compound channel. And the corresponding simulated results are shown to attain high accurcy. 展开更多
关键词 system dynamics model conveyance capacity symmetric compound channels resistance coefficient
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Competitive capacity of HIV-1 strains carrying M184I or Y181I drug-resistant mutations 被引量:4
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作者 LI Jue LI Lin LI Han-ping ZHUANG Dao-min LIU Si-yang LIU Yong-jian BAO Zuo-yi WANG Zheng LI Jing-yun 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第9期1081-1086,共6页
Background Virus with nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse transcriptase inhibitors (NNRTIs) resistant mutations show different evolution tendencies when the anti-viral ther... Background Virus with nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse transcriptase inhibitors (NNRTIs) resistant mutations show different evolution tendencies when the anti-viral therapies are interrupted. Understanding the replication fitness of drug-resistant virus is important for the study of the prevalence of drug-resistance For this purpose, we characterized the replication capacity of HIV-1 virus carrying lamivudine (3TC) or nevirapine (NVP) resistant mutations. Methods 3TC and NVP resistant variants were induced in vitro by selecting wild type virus in the presence of drugs. For the competitive replication assay, drug-resistant variants were cocultured with wild-type virus in the presence or absence of drugs. The ratios of the viral species were determined over time by using a real-time RT-PCR-based assay. Results 3TC-resistant (M184I mutation) and NVP-resistant (Y181I mutation) virus should be selected in vitro in two different ways. The competitive replication assay showed that the ratio of virus carrying a M184I mutation increased from 98.8%, while the wild type virus decreased to 1.2% after 4 passages in the presence of 3TC; the percentage of virus carrying the Y181I mutation increased to 90.5%, while wild type virus decreased to 9.5% in the presence of NVP. In the absence of drugs, the ratio of virus carrying the M184I mutation decreased to 5.3%, while wild type virus increased to 94.7%; the ratio of virus carrying Y181I increased to 75%, while wild type virus decreased to 25% after 4 passages. Conclusions The NVP-resistant virus is fitter than wild type virus even in the absence of NVP that may be the reason that NNRTIs-resistant virus is spreading quickly. 展开更多
关键词 human immunodeficiency virus type 1 DRUG-resistance replication capacity
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