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Basic Mechanical Properties and Microstructural Analysis of Recycled Concrete
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作者 陈宝璠 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第1期104-109,共6页
The regeneration aggregate, natural aggregate, POO42.5 R Portland cement, coal fly ash, and slag powders S95 graining blast furnace, homemade P(AA-co-MA)/PEG carboxylic acid water reducing agent, were used together ... The regeneration aggregate, natural aggregate, POO42.5 R Portland cement, coal fly ash, and slag powders S95 graining blast furnace, homemade P(AA-co-MA)/PEG carboxylic acid water reducing agent, were used together with recycled concrete aggregate in different regeneration rates to prepare recycled concrete (RC). The influences of different renewable aggregate ratios on the basic RC replacement mechanical properties, uniaxial compression stress and strain curve, and the elastic modulus and rebound value were investigated.The results show that RC mechanical properties decreases with renewable aggregate replacement rate increasing. The prolongation can reduce the reduced span. 展开更多
关键词 recycled concrete (RC) regeneration aggregate replacement rate mechanical properties uniaxial compression stress
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Long term performance of recycled concrete beams with different water-cement ratio and recycled aggregate replacement rate
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作者 Jingwei YING Feiming SU Shuangren CHEN 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2022年第3期302-315,共14页
The purpose of this study is to reveal the service performance of recycled aggregate concrete(RAC)components for different values of water-cement ratio and replacement rate of recycled coarse aggregate(RCA).Generally,... The purpose of this study is to reveal the service performance of recycled aggregate concrete(RAC)components for different values of water-cement ratio and replacement rate of recycled coarse aggregate(RCA).Generally,the concrete strength decreases with the increase of the replacement rate of RCA,in order to meet the strength requirements when changing the replacement rate of RCA,it is necessary to change the water-cement ratio at the same time.Therefore,the axial compressive strengths of prism with 25 mix proportions,the short-term mechanical properties and long-term deformation properties of reinforced concrete beams were tested respectively by changing water-cement ratio and RCA replacement rate.The bearing capacity and the strain nephogram of samples under different loads were obtained using the Digital Image Correlation(DIC)method,and a self-made gravity loading experimental device was used for long-term deformation investigation.Results showed that the damage pattern of RAC was the same as that of natural aggregate concrete(NAC),but the brittleness was more pronounced.The brittleness of concrete before failure can be reduced more effectively by adjusting the replacement rate of RCA than by adjusting the water-cement ratio.The water-cement ratio has an evident influence on the axial compressive strength and early creep of concrete,while the replacement rate of RCA has a remarkable effect on the long-term deformation of the concrete beams. 展开更多
关键词 recycled concrete BEAM the replacement rate of recycled coarse aggregate water-cement ratio digital image correlation
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Correlation study between pre-operative platelet aggregation rate and peri-operative blood product application in patients with off-pump coronary artery bypass grafting
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作者 廖博 《China Medical Abstracts(Internal Medicine)》 2017年第1期33-34,共2页
Objective To explore the impact of pre-operative platelet aggregation rate(PAR)on off-pump coronary artery bypass grafting(OPCABG),meanwhile to study the relationship between platelet function and blood product applic... Objective To explore the impact of pre-operative platelet aggregation rate(PAR)on off-pump coronary artery bypass grafting(OPCABG),meanwhile to study the relationship between platelet function and blood product application during peri-operative period in relevant patients.Methods A total of 172 patients receiving OPCABG in our hospita from 2014-01 to 2015-09 were en- 展开更多
关键词 rate PAR Correlation study between pre-operative platelet aggregation rate and peri-operative blood product application in patients with off-pump coronary artery bypass grafting
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Obstructive Sleep Apnea Affecting Platelet Reactivity in Patients Undergoing Percutaneous Coronary Intervention 被引量:4
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作者 Xiao-Min Jiang Xue-Song Qian +4 位作者 Xiao-Fei Gao Zhen Ge Nai-Liang Tian Jing Kan Jun-Jie Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2018年第9期1023-1029,共7页
Background:The relationship between obstructive sleep apnea (OSA) and platelet reactivity in patients undergoing percutaneous coronary intervention (PCI) has not been defined.The present prospective,single-center... Background:The relationship between obstructive sleep apnea (OSA) and platelet reactivity in patients undergoing percutaneous coronary intervention (PCI) has not been defined.The present prospective,single-center study explored the relationship between platelet reactivity and OSA in patients with PCI.Methods:A total of 242 patients were finally included in the study.OSA was screened overnight by polysomnography.Platelet reactivity was assessed with a sequential platelet counting method,and the platelet maximum aggregation ratio (MAR) and average aggregation ratio were calculated.All patients were assigned per apnea-hypopnea index (AHI) to non-OSA (n =128) and OSA (n =l 14) groups.The receiver operating characteristic curve analysis was used to evaluate the accuracy of AHI for high platelet reactivity (HPR) on aspirin and clopidogrel,and multivariable logistic regression was used to determine the independent predictors of HPR on aspirin and clopidogrel.Results:Median AHI was significantly higher in the OSA group than in the non-OSA group (34.5 events/h vs.8.1 events/h,Z =-13.422,P 〈 0.001).Likewise,median arachidonic acid-and adenosine diphosphate-induced maximum aggregation rate (MAR) in the OSA group was significantly higher than those in the non-OSA group (21.1% vs.17.7%,Z=-3.525,P 〈 0.001 and 45.8% vs.32.2%,Z =-5.708,P 〈 0.001,respectively).Multivariable logistic regression showed that OSA was the only independent predictor for HPR on aspirin (odds ratio [OR]:1.055,95% confidence interval [CI]:1.033-1.077,P 〈 0.001) and clopidogrel (OR:1.036,95% CI:1.017-1.056,P 〈 0.001).The cutoffvalue of AHI for HPR on aspirin was 45.2 events/h (sensitivity 47.1% and specificity 91.3%),whereas cutoffvalue of AHI for HPR on clopidogrel was 21.3 events/h (sensitivity 68.3% and specificity 67.7%). 展开更多
关键词 Antiplatelet Drugs Maximum Aggregation rate Obstructive Sleep Apnea Percutaneous Coronary Intervention Platelet Reactivity
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Effect of Xiaoyu Zhixue Tablet(消瘀止血片) on the Expression of Platelet Membrane Glycoprotein Ⅰb/Ⅸ/Ⅴ Complex in Patients with Chronic Renal Failure 被引量:5
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作者 秦铀 沈霖 +2 位作者 卢芙蓉 石威 刘建国 《Chinese Journal of Integrative Medicine》 SCIE CAS 2008年第2期83-87,共5页
Objective: To investigate the effect of Xiaoyu Zhixue Tablet (消瘀止血片, XYZXT) on the expression of platelet membrane glycoprotein (GP) Ⅰ b/Ⅸ/Ⅴ complex and GP Ⅰ b α in patients with chronic renal failure ... Objective: To investigate the effect of Xiaoyu Zhixue Tablet (消瘀止血片, XYZXT) on the expression of platelet membrane glycoprotein (GP) Ⅰ b/Ⅸ/Ⅴ complex and GP Ⅰ b α in patients with chronic renal failure (CRF) in early metaphase. Methods: Fifty-one patients with CRF in early metaphase (treated group) were treated with XYZXT, 3 months as the course of treatment for 2 courses. The previous therapies remained unchanged. Flow cytometry was used to assess the expression of platelet GP Ⅰb/Ⅸ/Ⅴ complex and GP Ⅰb α in patients with CRF, and turbidity method was used to determine the platelet maximum aggregation rate (MAR), meanwhile the renal function was measured. The final data were compared with those before the treatment, and with those in the normal control group (31 healthy subjects). Results: Compared with the normal control group, expressions of GP Ⅰ b/Ⅸ/Ⅴ complex and GPⅠb α, and platelet MAR in CRF patients were significantly lower (P=0.007,P=0.001,P=0.009) before the treatment; after the treatment with XYZXT, the above indexes in CRF patients were remarkably increased (P=0.033,P=0.026, P=0.045), but still lower than those in the normal control group, however, it was not statistically significant. Conclusion: (1) The expression of GP Ⅰ b/Ⅸ/Ⅴ complex in CRF patients of early metaphase was decreased, which lead to platelet aggregation dysfunction. This might be one of the reasons for the hemorrhagic trend in CRF. (2) XYZXT was able to upgrade expressions of GP Ⅰb/Ⅸ/Ⅴ complex and GPⅠb α in CRF patients, improve platelet function and clown-regulate platelet activation in patients with CRF. 展开更多
关键词 chronic renal failure platelet membrane glycoproteins platelet maximum aggregation rate Xiaoyu Zhixue Tablet
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Influence of particle size on the aggregation behavior of nanoparticles: Role of structural hydration layer 被引量:2
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作者 Hongyan Sun Ruyuan Jiao +2 位作者 Guangyu An Hui Xu Dongsheng Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第5期33-42,共10页
More and more attention has been paid to the aggregation behavior of nanoparticles, but little research has been done on the effect of particle size. Therefore, this study systematically evaluated the aggregation beha... More and more attention has been paid to the aggregation behavior of nanoparticles, but little research has been done on the effect of particle size. Therefore, this study systematically evaluated the aggregation behavior of nano-silica particles with diameter 130–480 nm at different initial particle concentration, pH, ionic strength, and ionic valence of electrolytes. The modified Smoluchowski theory failed to describe the aggregation kinetics for nano-silica particles with diameters less than 190 nm. Besides, ionic strength, cation species and p H all affected fast aggregation rate coefficients of 130 nm nanoparticles. Through incorporating structural hydration force into the modified Smoluchowski theory, it is found that the reason for all the anomalous aggregation behavior was the different structural hydration layer thickness of nanoparticles with various sizes. The thickness decreased with increasing of particle size, and remained basically unchanged for particles larger than 190 nm. Only when the distance at primary minimum was twice the thickness of structural hydration layer, the structural hydration force dominated, leading to the higher stability of nanoparticles. This study clearly clarified the unique aggregation mechanism of nanoparticles with smaller size, which provided reference for predicting transport and fate of nanoparticles and could help facilitate the evaluation of their environment risks. 展开更多
关键词 NANOPARTICLES Particle size Aggregation rate coefficient Structural hydration layer Derjaguin LANDAU Verwey and Overbeek(DLVO)theory
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Application of Machine Learning for Online Reputation Systems 被引量:3
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作者 Ahmad Alqwadri Mohammad Azzeh Fadi Almasalha 《International Journal of Automation and computing》 EI CSCD 2021年第3期492-502,共11页
Users on the Internet usually require venues to provide better purchasing recommendations.This can be provided by a reputation system that processes ratings to provide recommendations.The rating aggregation process is... Users on the Internet usually require venues to provide better purchasing recommendations.This can be provided by a reputation system that processes ratings to provide recommendations.The rating aggregation process is a main part of reputation systems to produce global opinions about the product quality.Naive methods that are frequently used do not consider consumer profiles in their calculations and cannot discover unfair ratings and trends emerging in new ratings.Other sophisticated rating aggregation methods that use a weighted average technique focus on one or a few aspects of consumers′profile data.This paper proposes a new reputation system using machine learning to predict reliability of consumers from their profile.In particular,we construct a new consumer profile dataset by extracting a set of factors that have a great impact on consumer reliability,which serve as an input to machine learning algorithms.The predicted weight is then integrated with a weighted average method to compute product reputation score.The proposed model has been evaluated over three Movie Lens benchmarking datasets,using 10-folds cross validation.Furthermore,the performance of the proposed model has been compared to previous published rating aggregation models.The obtained results were promising which suggest that the proposed approach could be a potential solution for reputation systems.The results of the comparison demonstrated the accuracy of our models.Finally,the proposed approach can be integrated with online recommendation systems to provide better purchasing recommendations and facilitate user experience on online shopping markets. 展开更多
关键词 Reputation system rating aggregation machine learning consumer reliability user trust
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Fiscal Policy and Urban and Rural Residents' Marginal Propensity to Consume 被引量:2
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作者 Li Yongyou Zhong Xiaomin 《Social Sciences in China》 2013年第4期85-99,共15页
Based on the optimal consumption decisions of representative households and the relationship between their decisions and fiscal policy, we evaluate the impact of China's fiscal policy on urban and rural residents' m... Based on the optimal consumption decisions of representative households and the relationship between their decisions and fiscal policy, we evaluate the impact of China's fiscal policy on urban and rural residents' marginal propensity to consume. The result shows that since 1998 marginal propensity to consume has decreased by more than 20 percent, 'and the decrease is not only due to income distribution, economic development level, expectations, consumption structure and other factors, but also closely related to the application of fiscal policy. Among these factors, the overall impact of unanticipated fiscal policy shocks is significant and negative. The policy option of using unforeseen increases in tax revenue as a financing instrument greatly diminishes the positive effects of structural adjustment. Therefore, to increase household consumption, it is necessary not only to raise residents' capacity for consumption by increasing fiscal revenue but also to stabilize consumer expectations and promote the marginal propensity to consume through adjusting fiscal revenue and expenditure policies. 展开更多
关键词 residents' aggregate consumption rate marginal propensity to consume fiscalpolicy
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Specific ion effect of H^(+) on variably charged soil colloid aggregation 被引量:1
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作者 Yekun ZHANG Rui TIAN +1 位作者 Jia TANG Hang LI 《Pedosphere》 SCIE CAS CSCD 2020年第6期844-852,共9页
Specific ion effects(Hofmeister effects)have recently attracted the attention of soil scientists,and it has been found that ionic non-classic polarization plays an important role in the specific ion effect in soil.How... Specific ion effects(Hofmeister effects)have recently attracted the attention of soil scientists,and it has been found that ionic non-classic polarization plays an important role in the specific ion effect in soil.However,this explanation cannot be applied to H+.The aim of this work was to characterize the specific ion effect of H+on variably charged soil(yellow soil)colloid aggregation.The total average aggregation(TAA)rate,critical coagulation concentration(CCC),activation energy,and zeta potential were used to characterize and compare the specific ion effects of H+,K+,and Na+.Results showed that strong specific ion effects of H+,K+,and Na+existed in variably charged soil colloid aggregation.The TAA rate,CCC,and activation energy were sensitive to H+,and the addition of a small amount of H+changed the TAA rate,CCC,and activation energy markedly.The zeta potential results indicated that the specific ion effects of H+,K+,and Na+on soil colloid aggregation were caused by the specific ion effects of H+,K+,and Na+on the soil electric field strength.In addition,the origin of the specific ion effect for H+was its chemical adsorption onto surfaces,while those for alkali cations were non-classic polarization.This study indicated that H+,which occurs naturally in variably charged soils,will dominate variably charged soil colloid aggregation. 展开更多
关键词 activation energy chemical adsorption critical coagulation concentration dynamic light scattering Hofmeister effect total average aggregation rate zeta potential
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Effects of Ixeris Sonchifolia on Platelet Function and Hemorrheology of Type 2 Diabetes Mellitus Patients
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作者 朱亦堃 赵宝珍 +1 位作者 李兴 史书红 《Chinese Journal of Integrative Medicine》 SCIE CAS 2002年第3期175-178,共4页
Objective: To observe the effects of Ixeris sonchifolia Hance (ISH) on platelet function and hemorrheology in type 2 diabetes mellitus (DM) patients. Methods: Thirty-three type 2 DM patients were treated with 20 ml IS... Objective: To observe the effects of Ixeris sonchifolia Hance (ISH) on platelet function and hemorrheology in type 2 diabetes mellitus (DM) patients. Methods: Thirty-three type 2 DM patients were treated with 20 ml ISH per day, intravenously dripping for 15 days; 31 patients in the red sage treated group were treated with composite red sage injection intravenous dripping for 15 days, and their changes of platelet membrane glycoprotein Ⅱb/Ⅲa compound (GPⅡb/Ⅲa), granular membrane protein-140 (GMP-140), platelet aggregation rate (PAgR) and hemorrheology were observed. Results: After treatment with ISH, the GPⅡb/Ⅲa compound positive rate of 33 type 2 DM patients were lowered (P<0.05), GMP-140 showed lowering trend, PAgR obviously reduced, and compared with before treatment it showed significant difference; comparison between the two groups after treatment,it showed significant difference (P<0.05, P<0.01). At the same time, the various parameters of hemorrheology displayed significant improvement. There was no adverse effect during the course of treatment. Conclusion: ISH could improve platelet function and abnormal hemorrheology of type 2 DM patients, which is vital for the treatment of DM and their vascular lesion. 展开更多
关键词 type 2 diabetes mellitus Ixeris sonchifolia Hance platelet glycoprotein platelet aggregation rate hemorrheology
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