One of the core challenges faced by children with autism is repetitive motor behavior,which not only undermines their learning efficiency in the classroom but also makes it difficult for them to integrate smoothly int...One of the core challenges faced by children with autism is repetitive motor behavior,which not only undermines their learning efficiency in the classroom but also makes it difficult for them to integrate smoothly into inclusive educational settings,thereby hindering their social adaptation and overall development.This study adopted a single-case design focusing on a first-grade student with autism enrolled in a mainstream class at Xiangxue Primary School,Huangpu District,Guangzhou.Functional behavior assessment was conducted to systematically observe and analyze the student’s repetitive motor behaviors in class,on the basis of which an intervention plan was developed and implemented.The intervention incorporated antecedent control,replacement behavior training,and consequence management,supplemented by collaboration between school and family.The findings indicated that the frequency of repetitive motor behaviors decreased significantly after the intervention,while the student demonstrated improved classroom participation and peer interaction;these positive effects were maintained during the follow-up phase.The study suggests that in inclusive education settings,interventions guided by functional behavior assessment can effectively reduce problem behaviors in children with autism and enhance their classroom engagement and learning adaptability.展开更多
The method of extracting and describing the intended behavior of software precisely has become one of the key points in the fields of software behavior＇s dynamic and trusted authentication. In this paper, the author ...The method of extracting and describing the intended behavior of software precisely has become one of the key points in the fields of software behavior＇s dynamic and trusted authentication. In this paper, the author proposes a specified measure of extracting SIBDS （software intended behaviors describing sets） statically from the binary executable using the software＇s API functions invoking, and also introduces the definition of the structure used to store the SIBDS in detail. Experimental results demonstrate that the extracting method and the storage structure definition offers three strong properties： （i） it can describe the software＇s intended behavior accurately; （ii） it demands a small storage expense; （iii） it provides strong capability to defend against mimicry attack.展开更多
Functional behavior assessment(FBA)and behavioral intervention plans(BIPs)can be effective for students with attention deficit hyperactivity disorder(ADHD);however,teachers may face difficulties when implementing FBA pr...Functional behavior assessment(FBA)and behavioral intervention plans(BIPs)can be effective for students with attention deficit hyperactivity disorder(ADHD);however,teachers may face difficulties when implementing FBA procedures and,in turn,BIPs because of lack of time,insufficient training,and multiplicity of beliefs.Thus,it is important to identify the difficulties teachers may face and the obstacles that can deter them from implementing intervention plans.This is a worthwhile endeavor because nearly all classrooms will have students with behavioral problems who will benefit from specifically designed educational interventions.This study aimed to identify the difficulties in applying FBA and the barriers in implementing BIPs among Saudi teachers in specialized ADHD programs.Using the descriptive-analytical approach,a questionnaire targeting difficulties and barriers was admi-nistered to 209 public school teachers from specialized ADHD programs in Saudi Arabia.The results revealed that the difficulty level of applying FBA in ADHD programs was high.The level of barriers in implementing BIPs was moderate.Finally,the study indicated that barriers in implementing BIPs could be predicted by the difficulties of applying FBA.The results suggest the importance offinding better practices,restructuring the provision of ADHD programs,training teachers,improving assessment tool availability,and ensuring cooperation between school administrators and teachers.展开更多
The Doubly Salient Electromagnetic Generator(DSEG) is a promising candidate in aircraft generator application due to the simplicity, robustness and reliability. However, the field windings and the armature windings ar...The Doubly Salient Electromagnetic Generator(DSEG) is a promising candidate in aircraft generator application due to the simplicity, robustness and reliability. However, the field windings and the armature windings are strongly coupled, which makes the inductance characteristics non-linear and too complex to model. The complex model with low precision also leads to difficulties in modeling and analysis of the entire aircraft Electrical Power System(EPS). A behavior level modeling method based on modified inductance Support Vector Machine(SVM) is proposed. The Finite Element Analysis(FEA) inductance data are modified based on the experiment results to improve the precision. A functional level modeling method based on input–output characteristics SVM is also proposed. The two modeling methods are applied to a 9 kW DSEG prototype. The steady state and transient process precision of the proposed methods are proved by comparing with the experiment results. Meanwhile, the modeling time consumption, the application time consumption and the calculation resource demand are compared. The DSEG behavior and functional modeling methods provide precious results with high efficiency, which accelerates theoretical analysis and expands the application foreground of the DSEG in the aircraft EPS.展开更多
In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the co...In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the corresponding results for Marcinkiewicz integral and its fractional version with kernels satisfying L_α~q-Dini condition are also given.展开更多
The longitudinal structure function with shadowing correction according to the nonlinear effects of the gluon density behavior at low x is considered. The solution of the GLR-MQ evolution equation for the gluon densit...The longitudinal structure function with shadowing correction according to the nonlinear effects of the gluon density behavior at low x is considered. The solution of the GLR-MQ evolution equation for the gluon density shows that the FL^g（x, Q2） behavior can be tamed by the singularity at low x values. Comparing our results with H1 data at R=4 GeV-1 shows that at very low x this behavior is completely tamed by taking shadowing correction into account.展开更多
AIM To determine the relationship between chronic kidney disease(CKD) awareness(CKD-A), self-management behaviors(CKD-SMB) knowledge, performance of CKDSMBs, health literacy(HL) and kidney function. METHODS Participan...AIM To determine the relationship between chronic kidney disease(CKD) awareness(CKD-A), self-management behaviors(CKD-SMB) knowledge, performance of CKDSMBs, health literacy(HL) and kidney function. METHODS Participants were eligible patients attending an outpatient nephrology clinic. Participants were administered: Newest Vital Sign to measure HL, CKD self-managementknowledge tool(CKD-SMKT) to assess knowledge, past performance of CKD-SMB, CKD-A. Estimated GFR(e GFR) was determined using the MDRD-4 equation. Duration of clinic participation and CKD cause were extracted from medical charts. RESULTS One-hundred-fifty patients participated in the study. e GFRs ranged from 17-152 m L/min per 1.73 m2. Majority(83%) of respondents had stage 3 or 4 CKD, low HL(63%), and were CKD aware(88%). Approximately 40%(10/25) of patients in stages 1 and 2 and 6.4%(8/125) in stages 3 and 4 were unaware of their CKD. CKD-A differed with stage(P < 0.001) but not by HL level, duration of clinic participation, or CKD cause. Majority of respondents(≥ 90%) correctly answered one or more CKD-SMKT items. Knowledge of one behavior, "controlling blood pressure" differed significantly by CKD-A. CKD-A was associated with past performance of two CKD-SMBs, "controlling blood pressure"(P = 0.02), and "keeping healthy body weight"(P = 0.01). Adjusted multivariate analyses between CKD-A and:(1) HL; and(2) CKD-SMB knowledge were nonsignificant. However, there was a significant relationship between CKD-A and kidney function after controlling for demographics, HL, and CKD-SMB(P < 0.05). CONCLUSION CKD-A is not associated with HL, or better CKD-SMBs. CKD-A is significantly associated with kidney function and substantially lower e GFR, suggesting the need for focused patient education in CKD stages 1.展开更多
Bamboo is a unique fiber-reinforced bio-composite with fibers embedded into a parenchyma cell matrix.We conducted axial compression tests on bamboo blocks prepared from bottom to top,and from inner to outer portions o...Bamboo is a unique fiber-reinforced bio-composite with fibers embedded into a parenchyma cell matrix.We conducted axial compression tests on bamboo blocks prepared from bottom to top,and from inner to outer portions of the culm.The apparent Young’s modulus and compressive strength of whole thickness bamboo blocks exhibited slight increases with increasing height along the culm,due to slight increases of fiber volume fraction(Vf)from 28.4 to 30.4%.Other blocks showed a significant increase in apparent Young’s modulus and strength from the inner to outer part of the culm wall,mainly owing to a sharp increase of Vf from 17.1 to 59.8%.With a decrease of fiber fraction volume there was a transition from relatively brittle behavior to very ductile behavior in bamboo blocks.Results indicated that stiffness and strength of bamboo was primarily due to fiber in compression,and ductility of bamboo was provided by the parenchyma cell matrix acting as a natural fiber-reinforced composite.展开更多
We consider the limiting property of the distribution function of L^p function at endpoints 0 and ∞ and prove that for λ 〉 0 the following two equations limλ→＋∞λ^p（{x ： ｜f（x）｜ 〉 λ}） = 0, limλ→0＋λ^...We consider the limiting property of the distribution function of L^p function at endpoints 0 and ∞ and prove that for λ 〉 0 the following two equations limλ→＋∞λ^p（{x ： ｜f（x）｜ 〉 λ}） = 0, limλ→0＋λ^p（{x ： ｜f（x）｜ 〉 λ}） = 0hold for f ∈ L^p（Rn） with 1 ≤ p 〈 ∞. This result is naturally applied to many operators of type（p, q） as well.展开更多
The neurocircuitries that constitute the corticostriato-thalamo-cortical（CSTC） circuit provide a framework for bridging gaps between neuroscience and executive function in attention deficit hyperactivity disorder（A...The neurocircuitries that constitute the corticostriato-thalamo-cortical（CSTC） circuit provide a framework for bridging gaps between neuroscience and executive function in attention deficit hyperactivity disorder（ADHD）, but it has been difficult to identify the mechanisms for regulating emotional problems from the understanding of ADHD comorbidity with disruptive behavior disorders（DBD）. Research based on ＂cool＇＇ and ＂hot＇＇executive functional theory and the dual pathway models,which are thought of as applied response inhibition and delay aversion, respectively, within the neuropsychological view of ADHD, has shed light on emotional responding before and after decontextualized stimuli, while CSTC circuit-related domains have been suggested to explain the different emotional symptoms of ADHD with or without comorbid DBD. This review discusses the role of abnormal connections in each CSTC circuit, especially in the emotion circuit, which may be responsible for targeted executive dysfunction at the neuroscience level. Thus, the two major domains – abstract thinking（cool） and emotional trait（hot） – trigger the mechanism of onset of ADHD.展开更多
The generalized fractional elastic models govern the stochastic motion of several many-body systems,e.g., polymers, membranes, and growing interfaces. This paper focuses on the exact formulations and their asymptotic ...The generalized fractional elastic models govern the stochastic motion of several many-body systems,e.g., polymers, membranes, and growing interfaces. This paper focuses on the exact formulations and their asymptotic behaviors of the average of the solutions of the generalized fractional elastic models. So we directly analyze the Cauchy problem of the averaged generalized elastic model involving time fractional derivative and the convolution integral of a radially symmetric friction kernel with space fractional Laplacian.展开更多
The adsorption behaviors and dispersing properties of polycarboxylate superplasticizer(PCE) with different functional groups were systematically analyzed to reveal the theory and methods of modifying PCE molecular str...The adsorption behaviors and dispersing properties of polycarboxylate superplasticizer(PCE) with different functional groups were systematically analyzed to reveal the theory and methods of modifying PCE molecular structures and regulating PCE performances. By substituting carboxylic groups with sulfonic groups, ester groups or acylamino groups, respectively, modified PCEs with different functional groups were synthesized. Results show that introducing low amount of ester groups or sulfonic groups into the PCE molecules has no negative effects on the fluidity of cement paste, while introducing acylamino groups into PCE molecules significantly weakens the fluidity of cement paste. At low amount(when the molar ratio of sodium methallyl sulfonate to TPEG is lower than 0.4), the rapid adsorption of sulfonic groups onto the cement particles contributes to the high dispersing performance of the sulfonic group modified PCEs. When the substitution ratio of acrylic acid by sulfonic acid is higher than 0.4, the viscosity and the yield stress of cement paste increases sharply. Redundant sulfonic groups lead to the excessive charge density of the PCE, which contributes to the inhomogeneous adsorption on the cement grains and hence results in the decline of the dispersing performance. Substitution of carboxylic group by acylamino group or ester group slightly changes the viscosity as well as the yield stress of cement paste. Introducing sulfonic group into PCE molecule improves the adsorption behavior of PCEs, while introducing ester group or acylamino group into PCE depresses the adsorption properties.展开更多
The cognition and attitudes of resources environment affect environmental behavior of behavior subject,the changes of attitude and behavior become one of the key factors of influencing harmonious and healthy developme...The cognition and attitudes of resources environment affect environmental behavior of behavior subject,the changes of attitude and behavior become one of the key factors of influencing harmonious and healthy development of ecological environment. With PRA survey method for obtaining questionnaire data and based on behavior geography and social psychology theory,farming-pastoral,dry grassland,desert grassland, typical project village alpine grassland of returning fazing land to grasslands as an example,with main body cognitive perspective of the aid of resources,the article analyzed space dissimilation of stakeholders environmental cognitive and behavior preference response in the area of returning grazing land to grasslands from ecological environment from policy environment,ecological environment and family economic environment aspects. The results showed that： stakeholders judgment of Grassland degradation in different ecological function area had obvious regularity,the cognitive proportion of Grassland degradation gradually increase from farming-pastora to alpine savanes. The satisfaction from returning grazing land to grasslands showed a changing tendency of reversed U. stakeholders had more strongly negative cognition in the area of dry steppe and desertsteppe. From farming-pastoral to alpine savanes,the economic environment tend to worse situation. Negative environmental behaviors tend to increase,Positive behavior on the contrary.展开更多
文摘One of the core challenges faced by children with autism is repetitive motor behavior,which not only undermines their learning efficiency in the classroom but also makes it difficult for them to integrate smoothly into inclusive educational settings,thereby hindering their social adaptation and overall development.This study adopted a single-case design focusing on a first-grade student with autism enrolled in a mainstream class at Xiangxue Primary School,Huangpu District,Guangzhou.Functional behavior assessment was conducted to systematically observe and analyze the student’s repetitive motor behaviors in class,on the basis of which an intervention plan was developed and implemented.The intervention incorporated antecedent control,replacement behavior training,and consequence management,supplemented by collaboration between school and family.The findings indicated that the frequency of repetitive motor behaviors decreased significantly after the intervention,while the student demonstrated improved classroom participation and peer interaction;these positive effects were maintained during the follow-up phase.The study suggests that in inclusive education settings,interventions guided by functional behavior assessment can effectively reduce problem behaviors in children with autism and enhance their classroom engagement and learning adaptability.
基金the National Natural Science Foundation of China (60673071, 60743003, 90718005, 90718006)the National High Technology Research and Development Program of China (863 Program) (2006AA01Z442, 2007AA01Z411)
文摘The method of extracting and describing the intended behavior of software precisely has become one of the key points in the fields of software behavior＇s dynamic and trusted authentication. In this paper, the author proposes a specified measure of extracting SIBDS （software intended behaviors describing sets） statically from the binary executable using the software＇s API functions invoking, and also introduces the definition of the structure used to store the SIBDS in detail. Experimental results demonstrate that the extracting method and the storage structure definition offers three strong properties： （i） it can describe the software＇s intended behavior accurately; （ii） it demands a small storage expense; （iii） it provides strong capability to defend against mimicry attack.
基金The author extends his appreciation to the Deanship of Scientific Research at King Saud University for supporting this research work.
文摘Functional behavior assessment(FBA)and behavioral intervention plans(BIPs)can be effective for students with attention deficit hyperactivity disorder(ADHD);however,teachers may face difficulties when implementing FBA procedures and,in turn,BIPs because of lack of time,insufficient training,and multiplicity of beliefs.Thus,it is important to identify the difficulties teachers may face and the obstacles that can deter them from implementing intervention plans.This is a worthwhile endeavor because nearly all classrooms will have students with behavioral problems who will benefit from specifically designed educational interventions.This study aimed to identify the difficulties in applying FBA and the barriers in implementing BIPs among Saudi teachers in specialized ADHD programs.Using the descriptive-analytical approach,a questionnaire targeting difficulties and barriers was admi-nistered to 209 public school teachers from specialized ADHD programs in Saudi Arabia.The results revealed that the difficulty level of applying FBA in ADHD programs was high.The level of barriers in implementing BIPs was moderate.Finally,the study indicated that barriers in implementing BIPs could be predicted by the difficulties of applying FBA.The results suggest the importance offinding better practices,restructuring the provision of ADHD programs,training teachers,improving assessment tool availability,and ensuring cooperation between school administrators and teachers.
基金co-supported by the National Natural Science Foundation for Outstanding Young Scholar of China (No. 51622704)Jiangsu Provincial Science Funds for Distinguished Young Scientists of China (No. BK20150033)Postgraduate Research & Practice Innovation Program of Jiangsu Province (No. KYLX16_0358)
文摘The Doubly Salient Electromagnetic Generator(DSEG) is a promising candidate in aircraft generator application due to the simplicity, robustness and reliability. However, the field windings and the armature windings are strongly coupled, which makes the inductance characteristics non-linear and too complex to model. The complex model with low precision also leads to difficulties in modeling and analysis of the entire aircraft Electrical Power System(EPS). A behavior level modeling method based on modified inductance Support Vector Machine(SVM) is proposed. The Finite Element Analysis(FEA) inductance data are modified based on the experiment results to improve the precision. A functional level modeling method based on input–output characteristics SVM is also proposed. The two modeling methods are applied to a 9 kW DSEG prototype. The steady state and transient process precision of the proposed methods are proved by comparing with the experiment results. Meanwhile, the modeling time consumption, the application time consumption and the calculation resource demand are compared. The DSEG behavior and functional modeling methods provide precious results with high efficiency, which accelerates theoretical analysis and expands the application foreground of the DSEG in the aircraft EPS.
文摘In this paper, we establish the following limiting weak-type behaviors of Littlewood-Paley g-function g_φ: for nonnegative function f∈ L^1(R^n),■and ■where f_t(x) =t^(-n)f(t^(-1) x) for t > 0. Meanwhile, the corresponding results for Marcinkiewicz integral and its fractional version with kernels satisfying L_α~q-Dini condition are also given.
文摘The longitudinal structure function with shadowing correction according to the nonlinear effects of the gluon density behavior at low x is considered. The solution of the GLR-MQ evolution equation for the gluon density shows that the FL^g（x, Q2） behavior can be tamed by the singularity at low x values. Comparing our results with H1 data at R=4 GeV-1 shows that at very low x this behavior is completely tamed by taking shadowing correction into account.
文摘AIM To determine the relationship between chronic kidney disease(CKD) awareness(CKD-A), self-management behaviors(CKD-SMB) knowledge, performance of CKDSMBs, health literacy(HL) and kidney function. METHODS Participants were eligible patients attending an outpatient nephrology clinic. Participants were administered: Newest Vital Sign to measure HL, CKD self-managementknowledge tool(CKD-SMKT) to assess knowledge, past performance of CKD-SMB, CKD-A. Estimated GFR(e GFR) was determined using the MDRD-4 equation. Duration of clinic participation and CKD cause were extracted from medical charts. RESULTS One-hundred-fifty patients participated in the study. e GFRs ranged from 17-152 m L/min per 1.73 m2. Majority(83%) of respondents had stage 3 or 4 CKD, low HL(63%), and were CKD aware(88%). Approximately 40%(10/25) of patients in stages 1 and 2 and 6.4%(8/125) in stages 3 and 4 were unaware of their CKD. CKD-A differed with stage(P < 0.001) but not by HL level, duration of clinic participation, or CKD cause. Majority of respondents(≥ 90%) correctly answered one or more CKD-SMKT items. Knowledge of one behavior, "controlling blood pressure" differed significantly by CKD-A. CKD-A was associated with past performance of two CKD-SMBs, "controlling blood pressure"(P = 0.02), and "keeping healthy body weight"(P = 0.01). Adjusted multivariate analyses between CKD-A and:(1) HL; and(2) CKD-SMB knowledge were nonsignificant. However, there was a significant relationship between CKD-A and kidney function after controlling for demographics, HL, and CKD-SMB(P < 0.05). CONCLUSION CKD-A is not associated with HL, or better CKD-SMBs. CKD-A is significantly associated with kidney function and substantially lower e GFR, suggesting the need for focused patient education in CKD stages 1.
基金supported by Basic Scientific Research Funds of International Center for Bamboo and Rattan(1632016007)the National Science Foundation of China(31400519)
文摘Bamboo is a unique fiber-reinforced bio-composite with fibers embedded into a parenchyma cell matrix.We conducted axial compression tests on bamboo blocks prepared from bottom to top,and from inner to outer portions of the culm.The apparent Young’s modulus and compressive strength of whole thickness bamboo blocks exhibited slight increases with increasing height along the culm,due to slight increases of fiber volume fraction(Vf)from 28.4 to 30.4%.Other blocks showed a significant increase in apparent Young’s modulus and strength from the inner to outer part of the culm wall,mainly owing to a sharp increase of Vf from 17.1 to 59.8%.With a decrease of fiber fraction volume there was a transition from relatively brittle behavior to very ductile behavior in bamboo blocks.Results indicated that stiffness and strength of bamboo was primarily due to fiber in compression,and ductility of bamboo was provided by the parenchyma cell matrix acting as a natural fiber-reinforced composite.
基金Supported by the National Natural Science Foundation of China(Grant Nos.114713091127116211561062)
文摘We consider the limiting property of the distribution function of L^p function at endpoints 0 and ∞ and prove that for λ 〉 0 the following two equations limλ→＋∞λ^p（{x ： ｜f（x）｜ 〉 λ}） = 0, limλ→0＋λ^p（{x ： ｜f（x）｜ 〉 λ}） = 0hold for f ∈ L^p（Rn） with 1 ≤ p 〈 ∞. This result is naturally applied to many operators of type（p, q） as well.
基金supported by a Project of Shanghai Municipal Health and Family Planning Commission (201540114)a Key Specialty Project of Shanghai Municipal Health and Family Planning Commission grant for Child Psychiatry (ZK2015B01)a Research Project of the Shanghai Changning Health and Family Planning Commission grant (20164Y013)
文摘The neurocircuitries that constitute the corticostriato-thalamo-cortical（CSTC） circuit provide a framework for bridging gaps between neuroscience and executive function in attention deficit hyperactivity disorder（ADHD）, but it has been difficult to identify the mechanisms for regulating emotional problems from the understanding of ADHD comorbidity with disruptive behavior disorders（DBD）. Research based on ＂cool＇＇ and ＂hot＇＇executive functional theory and the dual pathway models,which are thought of as applied response inhibition and delay aversion, respectively, within the neuropsychological view of ADHD, has shed light on emotional responding before and after decontextualized stimuli, while CSTC circuit-related domains have been suggested to explain the different emotional symptoms of ADHD with or without comorbid DBD. This review discusses the role of abnormal connections in each CSTC circuit, especially in the emotion circuit, which may be responsible for targeted executive dysfunction at the neuroscience level. Thus, the two major domains – abstract thinking（cool） and emotional trait（hot） – trigger the mechanism of onset of ADHD.
基金Supported by the Program for New Century Excellent Talents in University under Grant No.NCET-09-0438the National Natural Science Foundation of China under Grant Nos.11271173 and 11101330+1 种基金the Starting Research Fund from the Xi’an University of Technology under Grant No.108-211206the Scientific Research Program Funded by Shaanxi Provincial Education Department under Grant No.2013JK0581
文摘The generalized fractional elastic models govern the stochastic motion of several many-body systems,e.g., polymers, membranes, and growing interfaces. This paper focuses on the exact formulations and their asymptotic behaviors of the average of the solutions of the generalized fractional elastic models. So we directly analyze the Cauchy problem of the averaged generalized elastic model involving time fractional derivative and the convolution integral of a radially symmetric friction kernel with space fractional Laplacian.
基金Funded by the National Natural Science Foundation of China(No.51808369)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.18KJB560016)+3 种基金the Opening Project of State Key Laboratory of Green Building Materials(No.YA-615)the State Key Laboratory of Silicate Materials for Architectures(No.SYSJJ2018-09)Science and Technology Project of Jiangsu Provincal Department of Housing and Urban-Rural Construction(No.2018ZD049)the Natural Science Foundation of Suzhou University of Science and Technology(No.XKQ2018009)
文摘The adsorption behaviors and dispersing properties of polycarboxylate superplasticizer(PCE) with different functional groups were systematically analyzed to reveal the theory and methods of modifying PCE molecular structures and regulating PCE performances. By substituting carboxylic groups with sulfonic groups, ester groups or acylamino groups, respectively, modified PCEs with different functional groups were synthesized. Results show that introducing low amount of ester groups or sulfonic groups into the PCE molecules has no negative effects on the fluidity of cement paste, while introducing acylamino groups into PCE molecules significantly weakens the fluidity of cement paste. At low amount(when the molar ratio of sodium methallyl sulfonate to TPEG is lower than 0.4), the rapid adsorption of sulfonic groups onto the cement particles contributes to the high dispersing performance of the sulfonic group modified PCEs. When the substitution ratio of acrylic acid by sulfonic acid is higher than 0.4, the viscosity and the yield stress of cement paste increases sharply. Redundant sulfonic groups lead to the excessive charge density of the PCE, which contributes to the inhomogeneous adsorption on the cement grains and hence results in the decline of the dispersing performance. Substitution of carboxylic group by acylamino group or ester group slightly changes the viscosity as well as the yield stress of cement paste. Introducing sulfonic group into PCE molecule improves the adsorption behavior of PCEs, while introducing ester group or acylamino group into PCE depresses the adsorption properties.
基金Supported by the National Natural Science Fund(40971039)Gansu Province Science and Technology Support Program(1011FKCA157)the Fundamental Research Funds Project of Colleges and Universities in Gansu Province
文摘The cognition and attitudes of resources environment affect environmental behavior of behavior subject,the changes of attitude and behavior become one of the key factors of influencing harmonious and healthy development of ecological environment. With PRA survey method for obtaining questionnaire data and based on behavior geography and social psychology theory,farming-pastoral,dry grassland,desert grassland, typical project village alpine grassland of returning fazing land to grasslands as an example,with main body cognitive perspective of the aid of resources,the article analyzed space dissimilation of stakeholders environmental cognitive and behavior preference response in the area of returning grazing land to grasslands from ecological environment from policy environment,ecological environment and family economic environment aspects. The results showed that： stakeholders judgment of Grassland degradation in different ecological function area had obvious regularity,the cognitive proportion of Grassland degradation gradually increase from farming-pastora to alpine savanes. The satisfaction from returning grazing land to grasslands showed a changing tendency of reversed U. stakeholders had more strongly negative cognition in the area of dry steppe and desertsteppe. From farming-pastoral to alpine savanes,the economic environment tend to worse situation. Negative environmental behaviors tend to increase,Positive behavior on the contrary.
