Aiming to improve the Structured Query Language( SQL) injection penetration test accuracy through the formalismguided test case generation,an attack purpose based attack tree model of SQL injection is proposed,and the...Aiming to improve the Structured Query Language( SQL) injection penetration test accuracy through the formalismguided test case generation,an attack purpose based attack tree model of SQL injection is proposed,and then under the guidance of this model, the formal descriptions for the SQL injection vulnerability feature and SQL injection attack inputs are established. Moreover,according to new coverage criteria,these models are instantiated and the executable test cases are generated.Experiments show that compared with the random enumerated test case used in other works,the test case generated by our method can detect the SQL injection vulnerability more effectively. Therefore,the false negative is reduced and the test accuracy is improved.展开更多
A fault injection model-oriented testing strategy was proposed for detecting component vulnerabilities.A fault injection model was defined,and the faults were injected into the tested component based on the fault inje...A fault injection model-oriented testing strategy was proposed for detecting component vulnerabilities.A fault injection model was defined,and the faults were injected into the tested component based on the fault injection model to trigger security exceptions.The testing process could be recorded by the monitoring mechanism of the strategy,and the monitoring information was written into the security log.The component vulnerabilities could be detected by the detecting algorithm through analyzing the security log.Lastly,some experiments were done in an integration testing platform to verify the applicability of the strategy.The experimental results show that the strategy is effective and operable.The detecting rate is more than 90%for vulnerability components.展开更多
Objective:This review is aimed at explaining the psychological problems related to capillary blood glucose(CBG)testing and insulin injection,as well as recommending essential strategies to solve the fear thereof.Metho...Objective:This review is aimed at explaining the psychological problems related to capillary blood glucose(CBG)testing and insulin injection,as well as recommending essential strategies to solve the fear thereof.Methods:Databases,including PubMed,Cumulative Index of Nursing and Allied Health Literature(CINAHL),Scopus,and Google Scholar,were searched to extract the relevant articles.Initially,the terms used to retrieve related studies were"fear of blood glucose monitoring","anxiety capillary blood glucose testing and insulin injection","psychological problems on blood glucose monitoring and insulin injection","diabetes management",and"diabetes mellitus".Results:Results showed that the psychological problems related to CBG testing and insulin injection were associated with the stress and depression experienced during diabetes self-monitoring of blood glucose.This psychological issue has its impacts such as nonadherence to medication as well as a lack of self-discipline in terms of CBG testing and insulin injection.Inadequate information,inappropriate perception,and pain/discomfort during pricking of fingers were the main reasons for the psychological issues in CBG testing and self-injection of insulin.Conclusions:The expected benefits of this review include the explanation of the issues related to the psychological problems in CBG testing and insulin injection among type 2 diabetes mellitus(T2DM)patients.This review article also provides the recommendations on providing counseling and empowering the patients on CBG monitoring and insulin injection.Moreover,family members should provide psychological support to reduce fear,anxiety,and distress arising from CBG testing and insulin injection.展开更多
There are the application scope limits for single differential-mode current injection test method, so in order to carry out injection susceptibility test for two-pieces equipment interconnected with both ends of a cab...There are the application scope limits for single differential-mode current injection test method, so in order to carry out injection susceptibility test for two-pieces equipment interconnected with both ends of a cable simultaneously, a double differential-mode current in- jection test method (DDMCI) is proposed. The method adopted the equivalence source wave theorem and Baum-Liu-Tesche(BLT) equation as its theory foundation. The equivalent corresponding relation between injection voltage and radiation electric field intensity is derived, and the phase relation between the two injection voltage sources is confirmed. The results indicate that the amplitude and phase of the equivalent injection voltage source is closely related to the S parameter of directional coupling device, the transmission line length, and the source vector in BLT equation, but has nothing to do with the reflection coefficient between the two equipment pieces. Therefore, by choosing the right amplitude and phase of the double injection voltage sources, the DDMCI test is equivalent to the radiation test for two interconnected equipment of a system.展开更多
In order to investigate the effects of fuel injection distribution on the scrarnjet combustor performance, there are conducted three sets of test on a hydrocarbon fueled direct-connect scramjet test facility. The resu...In order to investigate the effects of fuel injection distribution on the scrarnjet combustor performance, there are conducted three sets of test on a hydrocarbon fueled direct-connect scramjet test facility. The results of Test A, whose fuel injection is carried out with injectors located on the top-wall and the bottom-wall, show that the fuel injection with an appropriate close-front and centralized distribution would be of much help to optimize combustor performances. The results of Test B, whose fuel injection is performed at the optimal injection locations found in Test A, with a given equivalence ratio and different injection proportions for each injector, show that this injection mode is of little benefit to improve combustor performances. The results of Test C with a circumferential fuel injection distribution displaies the possibility of ameliorating combustor performance. By analyzing the effects of injection location parameters on combustor performances on the base of the data of Test C, it is clear that the injector location has strong coupled influences on combustor performances. In addition, an irmer-force synthesis specific impulse is used to reduce the errors caused by the disturbance of fuel supply and working state of air heater while assessing combustor performances.展开更多
Objective: To evaluate the effectiveness and safety of lyophilized Salvia salt of lithospermic acid powder for injection (SSLA) in treating coronary heart diseases angina pectoris (CHD-AP) of Xin-blood stasis syn...Objective: To evaluate the effectiveness and safety of lyophilized Salvia salt of lithospermic acid powder for injection (SSLA) in treating coronary heart diseases angina pectoris (CHD-AP) of Xin-blood stasis syndrome type, and to conduct the non-inferiority trial with Danshen injection (丹参注射液, DSI) as positive control. Methods: An non-inferiority clinical layered, segmented, randomized, and blinded trial on three parallel and multiple centered groups was conducted in 480 patients with stable effort angina grade Ⅰ , Ⅱand Ⅲ, who had two or more times of attack every week. The 240 patients in test group A were treated with SSLA 200 mg added in 250 ml of 5% glucose solution for intravenous dripping every day; the 120 patients in test group B were treated with SSLA but the dosage doubled; and the 120 patients in the control group were treated with DSI 20 ml daily in the same method as SSLA was given. The clinical effectiveness and safety were evaluated after the patients were treated for 14 days. Results: The results showed that the markedly effective rate in test groups A, B and control group was 37.45 %, 36.75 % and 30.09 % respectively, while the total effective rate in them was 88.09%, 89.74% and 67.26% respectively. Statistical significance was shown in comparisons of the therapeutic effect between control group with test group A and test group B, with that in the two test groups superior to that in the control group, and non-inferiority trial showed eligibility (P〈0.01). Adverse reaction appeared in 8 patients in the test groups and 2 in the control group. Conclusion: SSLA has definite therapeutic effect in treating patients with CHD-AP, with its effect not inferior to that of DSI, and no evident toxic-adverse reaction.展开更多
This study aimed to evaluate the feasibility and safety of a novel stent manufactured by metal injection molding(MIM)in clinical practice through animal experiments.Vessel stents were prepared using powder injection m...This study aimed to evaluate the feasibility and safety of a novel stent manufactured by metal injection molding(MIM)in clinical practice through animal experiments.Vessel stents were prepared using powder injection molding technology to considerably improve material utilization.The influence of MIM carbon impurity variation on the mechanical properties and corrosion resistance of 316L stainless steel was studied.In vitro cytotoxicity and animal transplantation tests were also carried out to evaluate the safety of MIM stents.The results showed that the performance of 316L stainless steel was very sensitive to the carbon content.Carbon fluctuations should be precisely controlled during MIM.All MIM stents were successfully implanted into the aortas of the dogs,and the MIM 316L stents had no significant cytotoxicity.The novel intravascular stent manufactured using MIM can maintain a stable form and structure with fast endothelialization of the luminal surface of the stent and ensure long-term patency in an animal model.The novel intravascular stent manufactured using MIM demonstrates favorable structural,physical,and chemical stability,as well as biocompatibility,offering promising application in clinical practice.展开更多
The quality of injection plastic molded parts relates to precise geometry,smooth surface,strength,durability,and other indicators that are associated with the mold,materials,injection process,and service environment.T...The quality of injection plastic molded parts relates to precise geometry,smooth surface,strength,durability,and other indicators that are associated with the mold,materials,injection process,and service environment.The warpage is one of main defects of injection products,which cost much time and materials.In order to minimize warpage to ensure the precise shape of molded parts,it needs to combine design,service conditions,process parameters,material properties,and other factors in the design and manufacturing.Finite element tools and material database are used to analyze the occurrence of warpage,and analysis results contribute to the improvement and optimization of injection molding process of typical parts.To find the optimal process parameters in the solution space,experimental data are used to establish backpropagation(BP)network for predicting warpage of a bearing stand based on analysis with Moldflow.With a proper transfer function and the BP network architecture,results from the BP network method satisfiy the criteria of accuracy.The optimal solutions are searched in the BP network by the genetic algorithm with the finding that the optimization method based on the BP network is efficient.展开更多
Background:Post-stroke dysphagia is one of the common clinical symptoms in the rehabilitation department of primary hospitals,which seriously affects the quality of life of patients and their families.Majority of medi...Background:Post-stroke dysphagia is one of the common clinical symptoms in the rehabilitation department of primary hospitals,which seriously affects the quality of life of patients and their families.Majority of medical workers have comprehensively studied post-stroke dysphagia as it easily induces inhalation pneumonia,asphyxia,and many other complications.At present,many methods for post-stroke dysphagia have been proved to be effective.With regard to comprehensive treatment effect,patient compliance,technology promotion difficulty,grassroots hospital operability,and other factors,we found that acupoint injection combined with nerve electrical stimulation is a good method worthy of promotion.Methods:A total of 130 patients with dysphagia after stroke were randomly divided into nerve electrical stimulation group(n=41),acupoint injection group(n=40),and comprehensive treatment group(nerve electrical stimulation plus acupoint injection,n=49).The therapeutic effect in each group was evaluated before treatment and 20 days after treatment using the improved water swallow test,video fluoroscopic swallowing study,and standardized swallowing assessment.Results:After 20 days of treatment,significant differences were noted in each group.The scores of improved water swallow test decreased from 4.10±0.74 to 2.12±0.95 in the nerve electrical stimulation group,4.00±0.78 to 2.28±1.04 in the acupoint injection group,and 4.16±0.77 to 1.73±0.79 in the comprehensive treatment group;video fluoroscopic swallowing study scores increased from 3.71±2.16 to 5.05±2.111 in the nerve electrical stimulation group,3.80±1.94 to 5.20±1.942 in the acupoint injection group,and 3.73±2.22 to 6.24±2.21 in the comprehensive treatment group;and standardized swallowing assessment scores of the three groups also decreased from 35.13±3.38 to 28.17±3.42,34.66±3.46,and 34.48±3.26 to 26.39±3.86,respectively.The overall scores of each group after treatment were significantly different from those before treatment(P<0.05),indicating that both nerve electrical stimulation and acupoint injection were effective for post-stroke dysphagia;the scores of nerve electrical stimulation group and acupoint injection group were similar,but those of the comprehensive treatment group were significantly better than the single treatments(P<0.05).It shows that the two treatment methods have synergistic effect,and combined treatments have more benefits.Conclusion:Nerve electrical stimulation and acupoint injection have a synergistic therapeutic effect on post-stroke dysphagia.The combined treatment is more beneficial to patients with post-stroke dysphagia than the single treatments.展开更多
Natural fractures are generally well developed in most hydrocarbon and geothermal reservoirs,which can produce complex fracture networks due to the activation of fractures during hydraulic stimulation.The present pape...Natural fractures are generally well developed in most hydrocarbon and geothermal reservoirs,which can produce complex fracture networks due to the activation of fractures during hydraulic stimulation.The present paper is devoted to developing a method to investigate the activation characteristics of fracture under injection-shearing coupled condition at laboratory scale.The fluid is injected into the single-fractured granite until the fracture is activated based on the triaxial direct shear tests.The results show that injection process can significantly influence the shear stress distribution field,resulting in release of shear stress and relative slip between the opposite sides of the fractured surface.The injectioninduced activation of fracture is strongly dependent on the stress states.When the normal stress increases,the injection-induced activation pressure increases,and the comparatively high normal stress can restrain the fracture activation.The fracture deformation mechanisms during fluid injection are also discussed preliminarily with the experimental data.The sensitivity of shear stress to fluid injection increases with increase of shear stress level,while it decreases under high normal stress.The results can facilitate our understanding of the natural fracture activation behavior during fluid pressure stimulation.展开更多
1 Scope This standard specifies the classification, techni cal requirements, test methods, quality appraisal pro- cedures, packing, marking, transportation, storage, quality certificate, and construction manual of non...1 Scope This standard specifies the classification, techni cal requirements, test methods, quality appraisal pro- cedures, packing, marking, transportation, storage, quality certificate, and construction manual of nonwater injection mix for blast furnace.展开更多
This study explores the molding processes by using the Multi-component-injection molding (MCM) method, in which monolithic products are molded by attaching mixed liquid-silicone-rubbers (LSRs) to polybutylene terephth...This study explores the molding processes by using the Multi-component-injection molding (MCM) method, in which monolithic products are molded by attaching mixed liquid-silicone-rubbers (LSRs) to polybutylene terephthalate (PBT) that has the characteristic of self-binding while burning due to Pt catalysts. It is seen that this method increases the binding force between LSR and PBT. The surfaces coated with Polytetrafluoroethylene (PTFE), Cr, Ni, etc. have excellent peeling with plastic and such surfaces are compared with those treated with hot forging die and micro blasting without coating. When peeling tests are performed at the specified polymerization temperature and molding time after LSR molding on these surfaces of hot working die molds without coating, these surfaces show excellent peeling of molds and LSR products. In particular, they show better peeling after micro blasting than surfaces with Cr and Ni coating as well as surfaces without coating, and the peeling strength also decreases. The results of contact angle and XPS analysis indicate that the LSR binding force is enhanced as an effect of catalysts, though it is not found by SEM. According to the XPS analysis, the structures of the surfaces are close to methyl and vinyl materials that are produced while LSR molding.展开更多
基金National Natural Science Foundation of China(No.51274150)Tianjin Major Project of Application Foundation and Advanced Technology,China(No.12JCZDJC27800)
文摘Aiming to improve the Structured Query Language( SQL) injection penetration test accuracy through the formalismguided test case generation,an attack purpose based attack tree model of SQL injection is proposed,and then under the guidance of this model, the formal descriptions for the SQL injection vulnerability feature and SQL injection attack inputs are established. Moreover,according to new coverage criteria,these models are instantiated and the executable test cases are generated.Experiments show that compared with the random enumerated test case used in other works,the test case generated by our method can detect the SQL injection vulnerability more effectively. Therefore,the false negative is reduced and the test accuracy is improved.
基金Project(513150601)supported by the National Pre-Research Project Foundation of China
文摘A fault injection model-oriented testing strategy was proposed for detecting component vulnerabilities.A fault injection model was defined,and the faults were injected into the tested component based on the fault injection model to trigger security exceptions.The testing process could be recorded by the monitoring mechanism of the strategy,and the monitoring information was written into the security log.The component vulnerabilities could be detected by the detecting algorithm through analyzing the security log.Lastly,some experiments were done in an integration testing platform to verify the applicability of the strategy.The experimental results show that the strategy is effective and operable.The detecting rate is more than 90%for vulnerability components.
基金the Layanan Beasiswa dan Pendanaan Riset Indonesia(LPDP)Scholarship scheme for supporting this study。
文摘Objective:This review is aimed at explaining the psychological problems related to capillary blood glucose(CBG)testing and insulin injection,as well as recommending essential strategies to solve the fear thereof.Methods:Databases,including PubMed,Cumulative Index of Nursing and Allied Health Literature(CINAHL),Scopus,and Google Scholar,were searched to extract the relevant articles.Initially,the terms used to retrieve related studies were"fear of blood glucose monitoring","anxiety capillary blood glucose testing and insulin injection","psychological problems on blood glucose monitoring and insulin injection","diabetes management",and"diabetes mellitus".Results:Results showed that the psychological problems related to CBG testing and insulin injection were associated with the stress and depression experienced during diabetes self-monitoring of blood glucose.This psychological issue has its impacts such as nonadherence to medication as well as a lack of self-discipline in terms of CBG testing and insulin injection.Inadequate information,inappropriate perception,and pain/discomfort during pricking of fingers were the main reasons for the psychological issues in CBG testing and self-injection of insulin.Conclusions:The expected benefits of this review include the explanation of the issues related to the psychological problems in CBG testing and insulin injection among type 2 diabetes mellitus(T2DM)patients.This review article also provides the recommendations on providing counseling and empowering the patients on CBG monitoring and insulin injection.Moreover,family members should provide psychological support to reduce fear,anxiety,and distress arising from CBG testing and insulin injection.
基金Project supported by Arm Pre-research Program (51333040101), National Defense 973 Program (6131380301 ), National Natural Science Foundation of China (61040003).
文摘There are the application scope limits for single differential-mode current injection test method, so in order to carry out injection susceptibility test for two-pieces equipment interconnected with both ends of a cable simultaneously, a double differential-mode current in- jection test method (DDMCI) is proposed. The method adopted the equivalence source wave theorem and Baum-Liu-Tesche(BLT) equation as its theory foundation. The equivalent corresponding relation between injection voltage and radiation electric field intensity is derived, and the phase relation between the two injection voltage sources is confirmed. The results indicate that the amplitude and phase of the equivalent injection voltage source is closely related to the S parameter of directional coupling device, the transmission line length, and the source vector in BLT equation, but has nothing to do with the reflection coefficient between the two equipment pieces. Therefore, by choosing the right amplitude and phase of the double injection voltage sources, the DDMCI test is equivalent to the radiation test for two interconnected equipment of a system.
文摘In order to investigate the effects of fuel injection distribution on the scrarnjet combustor performance, there are conducted three sets of test on a hydrocarbon fueled direct-connect scramjet test facility. The results of Test A, whose fuel injection is carried out with injectors located on the top-wall and the bottom-wall, show that the fuel injection with an appropriate close-front and centralized distribution would be of much help to optimize combustor performances. The results of Test B, whose fuel injection is performed at the optimal injection locations found in Test A, with a given equivalence ratio and different injection proportions for each injector, show that this injection mode is of little benefit to improve combustor performances. The results of Test C with a circumferential fuel injection distribution displaies the possibility of ameliorating combustor performance. By analyzing the effects of injection location parameters on combustor performances on the base of the data of Test C, it is clear that the injector location has strong coupled influences on combustor performances. In addition, an irmer-force synthesis specific impulse is used to reduce the errors caused by the disturbance of fuel supply and working state of air heater while assessing combustor performances.
基金Supported by the Fund of National Project of High.technicResearch and Development,(No.2003AA223269)
文摘Objective: To evaluate the effectiveness and safety of lyophilized Salvia salt of lithospermic acid powder for injection (SSLA) in treating coronary heart diseases angina pectoris (CHD-AP) of Xin-blood stasis syndrome type, and to conduct the non-inferiority trial with Danshen injection (丹参注射液, DSI) as positive control. Methods: An non-inferiority clinical layered, segmented, randomized, and blinded trial on three parallel and multiple centered groups was conducted in 480 patients with stable effort angina grade Ⅰ , Ⅱand Ⅲ, who had two or more times of attack every week. The 240 patients in test group A were treated with SSLA 200 mg added in 250 ml of 5% glucose solution for intravenous dripping every day; the 120 patients in test group B were treated with SSLA but the dosage doubled; and the 120 patients in the control group were treated with DSI 20 ml daily in the same method as SSLA was given. The clinical effectiveness and safety were evaluated after the patients were treated for 14 days. Results: The results showed that the markedly effective rate in test groups A, B and control group was 37.45 %, 36.75 % and 30.09 % respectively, while the total effective rate in them was 88.09%, 89.74% and 67.26% respectively. Statistical significance was shown in comparisons of the therapeutic effect between control group with test group A and test group B, with that in the two test groups superior to that in the control group, and non-inferiority trial showed eligibility (P〈0.01). Adverse reaction appeared in 8 patients in the test groups and 2 in the control group. Conclusion: SSLA has definite therapeutic effect in treating patients with CHD-AP, with its effect not inferior to that of DSI, and no evident toxic-adverse reaction.
基金the Major Project of the Ministry of Science and Technology of Changsha,China(No.kh2003014)the Hunan Provincial Natural Science Foundation,China(Nos.2018JJ2584,2018JJ3507)+1 种基金the Beijing Municipal Science and Technology Comission,China(No.D171100002917004)the Guangxi Science and Technology Plan Project,China(No.AD16380019).
文摘This study aimed to evaluate the feasibility and safety of a novel stent manufactured by metal injection molding(MIM)in clinical practice through animal experiments.Vessel stents were prepared using powder injection molding technology to considerably improve material utilization.The influence of MIM carbon impurity variation on the mechanical properties and corrosion resistance of 316L stainless steel was studied.In vitro cytotoxicity and animal transplantation tests were also carried out to evaluate the safety of MIM stents.The results showed that the performance of 316L stainless steel was very sensitive to the carbon content.Carbon fluctuations should be precisely controlled during MIM.All MIM stents were successfully implanted into the aortas of the dogs,and the MIM 316L stents had no significant cytotoxicity.The novel intravascular stent manufactured using MIM can maintain a stable form and structure with fast endothelialization of the luminal surface of the stent and ensure long-term patency in an animal model.The novel intravascular stent manufactured using MIM demonstrates favorable structural,physical,and chemical stability,as well as biocompatibility,offering promising application in clinical practice.
基金supported by a grant from the Ningbo Furja Industrial Corporation Limited
文摘The quality of injection plastic molded parts relates to precise geometry,smooth surface,strength,durability,and other indicators that are associated with the mold,materials,injection process,and service environment.The warpage is one of main defects of injection products,which cost much time and materials.In order to minimize warpage to ensure the precise shape of molded parts,it needs to combine design,service conditions,process parameters,material properties,and other factors in the design and manufacturing.Finite element tools and material database are used to analyze the occurrence of warpage,and analysis results contribute to the improvement and optimization of injection molding process of typical parts.To find the optimal process parameters in the solution space,experimental data are used to establish backpropagation(BP)network for predicting warpage of a bearing stand based on analysis with Moldflow.With a proper transfer function and the BP network architecture,results from the BP network method satisfiy the criteria of accuracy.The optimal solutions are searched in the BP network by the genetic algorithm with the finding that the optimization method based on the BP network is efficient.
基金This work was supported by the Jiangsu Provincial Administration of Traditional Chinese Medicine(No.YB201840).
文摘Background:Post-stroke dysphagia is one of the common clinical symptoms in the rehabilitation department of primary hospitals,which seriously affects the quality of life of patients and their families.Majority of medical workers have comprehensively studied post-stroke dysphagia as it easily induces inhalation pneumonia,asphyxia,and many other complications.At present,many methods for post-stroke dysphagia have been proved to be effective.With regard to comprehensive treatment effect,patient compliance,technology promotion difficulty,grassroots hospital operability,and other factors,we found that acupoint injection combined with nerve electrical stimulation is a good method worthy of promotion.Methods:A total of 130 patients with dysphagia after stroke were randomly divided into nerve electrical stimulation group(n=41),acupoint injection group(n=40),and comprehensive treatment group(nerve electrical stimulation plus acupoint injection,n=49).The therapeutic effect in each group was evaluated before treatment and 20 days after treatment using the improved water swallow test,video fluoroscopic swallowing study,and standardized swallowing assessment.Results:After 20 days of treatment,significant differences were noted in each group.The scores of improved water swallow test decreased from 4.10±0.74 to 2.12±0.95 in the nerve electrical stimulation group,4.00±0.78 to 2.28±1.04 in the acupoint injection group,and 4.16±0.77 to 1.73±0.79 in the comprehensive treatment group;video fluoroscopic swallowing study scores increased from 3.71±2.16 to 5.05±2.111 in the nerve electrical stimulation group,3.80±1.94 to 5.20±1.942 in the acupoint injection group,and 3.73±2.22 to 6.24±2.21 in the comprehensive treatment group;and standardized swallowing assessment scores of the three groups also decreased from 35.13±3.38 to 28.17±3.42,34.66±3.46,and 34.48±3.26 to 26.39±3.86,respectively.The overall scores of each group after treatment were significantly different from those before treatment(P<0.05),indicating that both nerve electrical stimulation and acupoint injection were effective for post-stroke dysphagia;the scores of nerve electrical stimulation group and acupoint injection group were similar,but those of the comprehensive treatment group were significantly better than the single treatments(P<0.05).It shows that the two treatment methods have synergistic effect,and combined treatments have more benefits.Conclusion:Nerve electrical stimulation and acupoint injection have a synergistic therapeutic effect on post-stroke dysphagia.The combined treatment is more beneficial to patients with post-stroke dysphagia than the single treatments.
基金The financial support by the National Key Research and Development Program of China(Grant No.2018YFC0809601)the National Natural Science Foundation of China(Grant No.51779252)+1 种基金the Major Technological Innovation Projects of Hubei,China(Grant No.2017AAA128)the Key Projects of the Yalong River Joint Fund of the National Natural Science Foundation of China(Grant No.U1865203)for this work are gratefully acknowledged。
文摘Natural fractures are generally well developed in most hydrocarbon and geothermal reservoirs,which can produce complex fracture networks due to the activation of fractures during hydraulic stimulation.The present paper is devoted to developing a method to investigate the activation characteristics of fracture under injection-shearing coupled condition at laboratory scale.The fluid is injected into the single-fractured granite until the fracture is activated based on the triaxial direct shear tests.The results show that injection process can significantly influence the shear stress distribution field,resulting in release of shear stress and relative slip between the opposite sides of the fractured surface.The injectioninduced activation of fracture is strongly dependent on the stress states.When the normal stress increases,the injection-induced activation pressure increases,and the comparatively high normal stress can restrain the fracture activation.The fracture deformation mechanisms during fluid injection are also discussed preliminarily with the experimental data.The sensitivity of shear stress to fluid injection increases with increase of shear stress level,while it decreases under high normal stress.The results can facilitate our understanding of the natural fracture activation behavior during fluid pressure stimulation.
文摘1 Scope This standard specifies the classification, techni cal requirements, test methods, quality appraisal pro- cedures, packing, marking, transportation, storage, quality certificate, and construction manual of nonwater injection mix for blast furnace.
文摘This study explores the molding processes by using the Multi-component-injection molding (MCM) method, in which monolithic products are molded by attaching mixed liquid-silicone-rubbers (LSRs) to polybutylene terephthalate (PBT) that has the characteristic of self-binding while burning due to Pt catalysts. It is seen that this method increases the binding force between LSR and PBT. The surfaces coated with Polytetrafluoroethylene (PTFE), Cr, Ni, etc. have excellent peeling with plastic and such surfaces are compared with those treated with hot forging die and micro blasting without coating. When peeling tests are performed at the specified polymerization temperature and molding time after LSR molding on these surfaces of hot working die molds without coating, these surfaces show excellent peeling of molds and LSR products. In particular, they show better peeling after micro blasting than surfaces with Cr and Ni coating as well as surfaces without coating, and the peeling strength also decreases. The results of contact angle and XPS analysis indicate that the LSR binding force is enhanced as an effect of catalysts, though it is not found by SEM. According to the XPS analysis, the structures of the surfaces are close to methyl and vinyl materials that are produced while LSR molding.