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Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis 被引量:1
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作者 Andreas Konrad Shahab Alizadeh +7 位作者 Abdolhamid Daneshjoo Saman Hadjizadeh Anvar Andrew Graham Ali Zahiri Reza Goudini Chris Edwards Carina Scharf David George Behm 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期186-194,共9页
Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence... Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in flexibility.Thus,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch training.Methods:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect meta-analysis.Moreover,by applying a mixed-effect model,we performed the respective subgroup analyses.To find potential relationships between stretch duration or age and effect sizes,we performed a meta-regression.Results:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic stretching.Moreover,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to males.However,further moderating analysis showed no significant relation or difference.Conclusion:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be applied.Something to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were found to play a significant role in ROM yields. 展开更多
关键词 FLEXIBILITY Long-term stretching Stretch training
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Kinematic analysis of flexible bipedal robotic systems
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作者 R.FAZEL A.M.SHAFEI S.R.NEKOO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期795-818,共24页
In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous researchers.What distinguishes the present research from similar works is the considera... In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous researchers.What distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic systems.This is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases considerably.Moreover,the human leg bones that are involved in walking are supported by viscoelastic muscles and ligaments.Therefore,for achieving more exact results,it is essential to model the robot links with viscoelastic properties.To this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of motion.The most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational force.The extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned goal.To overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue problem.By solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are determined.The effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of robotic systems are also studied.The findings of this parametric study reveal that the increase in the Kelvin-Voigt coefficient enhances the stability of the robotic system,while the increase in the modulus of elasticity has an opposite effect. 展开更多
关键词 bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient
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Levisticum officinale extract protects against CCl4-induced hepatotoxicity through anti-inflammatory,anti-fibrotic,and antioxidant properties in rats
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作者 Nahid Ghaedi Iran Pouraboli +1 位作者 Mansour Mirtadzadini Mohammad-mehdi Moeini-aghtaie 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第8期331-340,共10页
Objective:To investigate the hepatoprotective effects of Levisticum officinale extract on CCl4-induced hepatotoxicity.Methods:Different doses of Levisticum officinale extract were given orally to rats for 10 days,then... Objective:To investigate the hepatoprotective effects of Levisticum officinale extract on CCl4-induced hepatotoxicity.Methods:Different doses of Levisticum officinale extract were given orally to rats for 10 days,then rats received a single dose of CCl4(2.5 mL/kg,50%v/v in liquid paraffin).Biochemical and histopathological assays were performed to assess the effects of the extract on liver function and architecture.Moreover,antioxidant and oxidative markers as well as inflammatory and fibrotic indicators were measured.Results:Pretreatment with Levisticum officinale extract significantly mitigated CCl4-induced damage to liver structure,improved serum levels of alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,urea,total bilirubin,and total protein,enhanced glutathione content and superoxide dismutase and catalase activities in the liver,as well as decreased plasma and hepatic malondialdehyde levels.Immunohistochemical results demonstrated that the extract reduced Ki-67 andα-SMA expression and Masson’s trichrome staining revealed decreased liver collagen in rats treated with Levisticum officinale extract.Moreover,Levisticum officinale extract markedly decreased the gene expressions of TNF-α,IL-6,TGF-β1,MCP-1,and COX-2.Conclusions:Levisticum officinale extract exerts hepatoprotective effects on CCl4-induced hepatotoxicity through antioxidant,anti-inflammatory,and anti-fibrotic activities. 展开更多
关键词 Levisticum officinale CCL4 Inflammation Liver toxicity ANTIOXIDANT
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Spatial analysis of animal bites in Iran(2015-2020):A cross-sectional study
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作者 Hoda Amiri Khadijeh Yazdanparast +1 位作者 Mohsen Pourkhosravani Maryam Rastegar 《Journal of Acute Disease》 2024年第2期67-73,共7页
Objective:To investigate the distribution pattern of animal bites in Mirjaveh,Iran from 2015 to 2020.Methods:The data on animal bites were collected from the Department of Infectious Diseases,the provincial health cen... Objective:To investigate the distribution pattern of animal bites in Mirjaveh,Iran from 2015 to 2020.Methods:The data on animal bites were collected from the Department of Infectious Diseases,the provincial health center.Monthly climatic data on precipitation and temperature during the study period were also collected.The correlation between incidence and temperature,precipitation rate,land type,and altitude was also analyzed.Results:The results showed that men were more affected by animal bites than women(76.4%,P<0.001),and the highest incidence rate occurred in the age group of 5-19 years.The incidence rate of animal bites was found to be correlated with temperature and altitude.An increase in temperature was associated with a rise in the incidence rate of animal bites.The number of animal bites increased until 2019,possibly due to an increase in the number of dogs in the area.Conclusions:Targeted interventions should be implemented to reduce the incidence of animal bites,particularly among children,housewives,and students.Improving access to appropriate treatments,increasing public awareness of the hazards of animal bites,and increasing the number of vaccinated dogs in the area are essential strategies to be considered. 展开更多
关键词 Animal bites EPIDEMIOLOGY Zoonotic disease Iran
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BSN:Photometric Light Curve Analysis of Two Contact Binary Systems LS Del and V997 Cyg
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作者 Atila Poro Mehmet Tanriver +9 位作者 Elham Sarvari Shayan Zavvarei Hossein Azarara Laurent Corp Sabrina Baudart Asma Ababafi Nazanin Kahali Poor Fariba Zare Ahmet Bulut Ahmet Keskin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期192-213,共22页
The light curve analyses and orbital period variations for two contact binary stars,LS Del and V997 Cyg,are presented in this work which was conducted in the frame of the Binary Systems of South and North project Grou... The light curve analyses and orbital period variations for two contact binary stars,LS Del and V997 Cyg,are presented in this work which was conducted in the frame of the Binary Systems of South and North project Ground-based photometric observations were performed at two observatories in France.We used the Transiting Exoplanet Survey Satellite(TESS)data for extracting times of minima and light curve analysis of the targe systems.The O-C diagram for both systems displays a parabolic trend.LS Del and V997 Cyg’s orbital periods are increasing at rates of dP/dt=7.20×10^(-08)days yr^(-1)and dP/dt=2.54×10^(-08)days yr^(-1),respectively Therefore,it can be concluded that mass is being transferred from the less massive star to the more massive component with a rate of dM/dt=-1.96×10^(-7)M_(⊙)yr^(-1)for the LS Del system,and dM/dt=-3.83×10^(-7)M_(⊙)yr-1for V997 Cyg.The parameters of a third possible object in the system are also considered.The PHysics Of Eclipsing BinariEs Python code was used to analyze the light curves.The light curve solutions needed a cold starspot due to the asymmetry in the LS Del system’s light curve maxima.The mass ratio fill-out factor,and star temperature all indicate that both systems are contact binary types in this investigation.Two methods were applied to estimate the absolute parameters of the systems:one method relied on the parallax of Gaia DR3,and the other used a P-M relationship.The positions of the systems are also depicted on the M-L,M-R q-L_(ratio),and logM_(tot)-logJ_(0)diagrams.We recommend that further observations and investigations be done on the existence of a fourth body in this system. 展开更多
关键词 (stars:)binaries:eclipsing methods:observational stars:individual(LS Del and V997 Cyg)
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Mechanical properties and microstructural evolution of rheocast A356 semi-solid slurry prepared by annular electromagnetic stirring 被引量:1
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作者 Mohammad Taghi Asadi Khanouki 《China Foundry》 SCIE CAS CSCD 2023年第4期315-328,共14页
Nowadays,having an effective technique in preparing semi-solid slurries for rheocasting process seems to be an essential requirement.In this study,semi-solid slurry of A356 aluminum alloy was prepared by three-phase a... Nowadays,having an effective technique in preparing semi-solid slurries for rheocasting process seems to be an essential requirement.In this study,semi-solid slurry of A356 aluminum alloy was prepared by three-phase annular electromagnetic stirring(A-EMS)technique under different conditions.The effects of stirring current,pouring temperature and stirring time on microstructural evolution,mean particle size,shape factor and solid fraction were investigated.The rheocasting process was carried out by using a drop weight setup and to inject the prepared semi-solid slurry in optimal conditions into the step-die cavity.The filling behavior and mechanical properties of parts were studied.Microstructural evolution showed that the best semi-solid slurry which had fine spherical particles with the average size of~27μm and a shape factor of~0.8 was achieved at the stirring current of 70 A,melt pouring temperature of 670℃,and stirring time of 30 s.Under these conditions,the step-die cavity was completely filled at die preheating temperature of 470℃.The hardness increases by decreasing step thickness as well as die preheating temperature.Moreover,the tensile properties are improved at lower die preheating temperatures.The fracture surface,which consists of a complex topography,indicates a typical ductile fracture. 展开更多
关键词 semi-solid slurry annular electromagnetic stirring rheocast A356 aluminum alloy microstructural evolution mechanical properties magnetic flux density
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Prevalence of intestinal helminthes in owned dogs in Kerman city,Iran
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作者 Mohammad Mirzaei Majid Fooladi 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第9期735-737,共3页
ObjectiveTo survey the prevalence of canine gastrointestinal helminthes in dogs presented to the Veterinary faculty of the University of Kerman between May and November 2011.MethodsA total of 70 fecal samples were eva... ObjectiveTo survey the prevalence of canine gastrointestinal helminthes in dogs presented to the Veterinary faculty of the University of Kerman between May and November 2011.MethodsA total of 70 fecal samples were evaluated by the fecal sedimentation method.ResultsThe prevalence of gastrointestinal helminthes was 7.14%. The parasites most frequently detected were Toxocara canis (T. canis) (4.3%); Toxascaris leonina (T. leonina) (1.4%) and Teania spp. (1.4%). The age distribution of intestinal parasites in dogs showed that the dog less than 1 year old had a higher overall prevalence than those dogs over 12 months of age but there was not significant (P>0.05). Also there was no significant difference in the prevalence between male (7.7%) and female (6.5%) dogs (P>0.05).ConclusionsIt is thought that the reduction in the frequency of the dogs with those helminthes may be mainly a result of the improvement in breeding environment and the routine use of antihelmintics. The significance of zoonotic diseases caused by intestinal helminthes makes it necessary for us to know the infection status of domestic dogs and to take measures for further control. It is concluded that veterinarians have an important role in educating dog owners of these potential risks and means for preventing or minimizing zoonotic transmission. 展开更多
关键词 Gastrointestinal helminthes DOG KERMAN Iran
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Tectonic paleostress field and its impact on the geodynamic evolution of Central Iran, case study: the Shotori Mountain
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作者 Razieh ABBASPOUR Seyed Morteza MOUSAVI +2 位作者 Ahmad RASHIDI Mohammad Mahdi KHATIB Shahram SHAFIEIBAFTI 《Journal of Mountain Science》 SCIE CSCD 2023年第10期3018-3034,共17页
The Shotori mountain range is located along the northern terminus of the Nayband fault on the eastern and western domains of the Tabas and Lut blocks,respectively.This range with NNW-SSE trending and approximately 120... The Shotori mountain range is located along the northern terminus of the Nayband fault on the eastern and western domains of the Tabas and Lut blocks,respectively.This range with NNW-SSE trending and approximately 120 km long includes a series of thrust faults approaching the right-lateral strike-slip Nayband fault.Since the Shotori range has experienced various geological events since the Triassic,our investigations suggest that the basement of the Central Iranian subcontinent of the Shotori range contains the early Triassic deep sedimentary with normal faults which confirms Triassic tensional tectonic stress regime in the region.After the middle Triassic,the mountain range has experienced thrust and strike-slip regimes.Therefore,in this study,we reconstruct the stress regimes for different geological periods using fault-slip data.The inversion of faultslip data reveals drastic temporal changes in the maximum stress regime(σ1)over the Triassic,Jurassic,Cretaceous,Paleogene,Neogen,and Quaternary.The reconstruction of the stress field based on the age and direction of fault movement reveals that the direction of the maximum horizontal stress axis(σ1)under a tensional stress regime was approximately N129°in the Early Triassic.This stress regime is the cause of thinning and subsidence of the Shotori sedimentary basin.During the middle Triassic,theσ1 direction was about N81°and the upper Triassic,theσ1 direction was almost N115°.The middle Triassic and upper Triassic stress states exhibited two distinct strike-slip and compressive stress regimes.This stress regime led to the uplift of the Shotori sedimentary basin.During the Jurassic,the direction of the maximum horizontal stress axis(σ1)was~NW-SE under a compressive stress regime.During the Triassic,theσ1 direction was~N-S.This stress regime led to the formation of the high topography of the Shotori Mountain Range.In the Late Cretaceous,the direction of the maximum horizontal stress axis(σ1)under the extensional stress regime was~NE-SW.This stress regime led to the uplift of the Paleogen Dacite in eastern Iran.During the Neogene,theσ1 direction was~N60°.The Quaternary tectonic regime is strike-slip and theσ1 direction is~N50°,consistent with the current convergence direction of the Arabia–Eurasia plates.Our paleostress analysis reveals four recognized stress in this area,which includes compressional,transtensional,transpressional,and strike-slip regimes.Our findings indicated that the crustal diversity of the tectonic regimes was responsible for the formation of various geological structures,such as folds,faults by different mechanisms,and the present-day configuration of the Shotori sedimentary basin. 展开更多
关键词 PALEOSTRESS Fault-slip data GEODYNAMICS Shotori mountain range Tabas Central Iran
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Light Curve Analysis of the AP Dor Binary System using Ground-based and TESS Observations
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作者 A.Poro E.Fernández-Lajús +3 位作者 M.Madani G.Sabbaghian F.Nasrollahzadeh F.Jahediparizi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第9期114-128,共15页
The short-period eclipsing binary AP Dor’s first in-depth and multiband photometric solutions are presented.We made use of our eight nights of ground-based opportunity at a southern hemisphere observatory,and twelve ... The short-period eclipsing binary AP Dor’s first in-depth and multiband photometric solutions are presented.We made use of our eight nights of ground-based opportunity at a southern hemisphere observatory,and twelve sectors of TESS observations.We extracted eight and 1322 minima from our observations and TESS,respectively.We suggest a new linear ephemeris based on the trend of orbital period variations using the Markov chain Monte Carlo(MCMC)approach.The PHysics Of Eclipsing BinariEs(PHOEBE)Python code and the MCMC approach were utilized for the light curve analysis.This system did not require a starspot for the light curve solutions.We calculated the absolute parameters of the system by applying the Gaia DR3 parallax method.The orbital angular momentum(J_(0))of AP Dor indicates that this system is located in a region corresponding to contact binaries.According to our results,this system is an overcontact binary system with a mass ratio of 0.584,a fillout factor of 48%,and an inclination of 53°.The positions of component stars in the AP Dor system on the Hertzsprung–Russell diagram are found. 展开更多
关键词 (stars )binaries eclipsing-methods observational-stars individual(AP Dor)
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Assessment of pH-responsive nanoparticles performance on laboratory column flotation cell applying a real ore feed 被引量:23
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作者 Samiramis Nasirimoghaddam Ali Mohebbi +1 位作者 Mohsen Karimi M.Reza Yarahmadi 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第2期197-205,共9页
Nanoparticles(NPs)can promote the column flotation process in mining industry.Nanoparticles'effects on column flotation process(copper recovery,grade and flotation rate constant)are assessed in Sarcheshmeh Copper ... Nanoparticles(NPs)can promote the column flotation process in mining industry.Nanoparticles'effects on column flotation process(copper recovery,grade and flotation rate constant)are assessed in Sarcheshmeh Copper Complex,Iran,through response surface methodology(RSM)optimization technique.The c-Al2O3,a-Fe2O3,SiO2,and TiO2 nanoparticles are selected for these experiments.A flotation rate constant is chosen as a response to assess the effect of nanoparticles on flotation in its kinetic sense.The process p H and nanoparticle dosage are selected as the influential parameters.Results obtained from RSM indicated that the maximum percentage of Cu recovery and grade is obtained at p H of 12 and nanoparticle dosage of 6 kg/t,through a-Fe2O3 and c-Al2O3 nanoparticles,respectively.Applying nanoparticles in particular c-Al2O3 and a-Fe2O3 increases the Cu recovery by 8–10%together with the grade by 3–6%in a significant manner.It is revealed that nanoparticles could effectively be applied in enhancing the flotation performance. 展开更多
关键词 COLUMN FLOTATION NANOPARTICLES Cu recovery Response surface methodology
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Prediction of face advance rate and determination of the operation efficiency in retreat longwall mining panel using rock engineering system 被引量:6
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作者 Sajjad Aghababaei Hossein Jalalifar Gholamreza Saeedi 《International Journal of Coal Science & Technology》 EI 2019年第3期419-429,共11页
A new approach for prediction of face advance rete (FAR) prior to mining operation and determination of the operation efficiency after mining operation in retreat longwall mining panel is presented based upon the conc... A new approach for prediction of face advance rete (FAR) prior to mining operation and determination of the operation efficiency after mining operation in retreat longwall mining panel is presented based upon the concepts of rock engineering system (RES). For this purpose, six longwall panels considered in Parvadeh-I coal mine. Seven major effective parameters on FAR was selected including coal mine roof rating, gas propagation, safety factor of longwall face, ratio of joint spacing to cutting depth at longwall face, longwall face inclination, panel width, floor rock mass rating. To performance evaluation of the presented model, the relationship between the average vulnerability indexes of advance operation with FAR was determined in considered panels with coefficient of determination (R2) equal to 0.884 that indicate relatively acceptable correlation and compatibility. Investigations of the research indicated that it is possible to determine the actual operation efficiency under fair conditions by a RES-based model. The inevitable reduction of FAR for each longwall panel was determined by presented model that the difference amount between the maximum possible practical face advance rate (FARmpp) and recorded actual face advance rate (FARa) indicate the operation efficiency. Applied approach in this paper can be used to prediction of FAR in retreat longwall mining panel for same conditions that can have many benefits, including better and more accurate planning for the sales market and mine operation. Also, presented method in this paper can be applied as a useful tool to determination of actual operation efficiency for other sections and extraction methods in coal mines. 展开更多
关键词 FACE ADVANCE rate Rock engineering systems Operation efficiency LONGWALL mining Parvadeh-I coal mine
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Classification and assessment of rock mass parameters in Choghart iron mine using P-wave velocity 被引量:9
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作者 Mohammadreza Hemmati Nourani Mohsen Taheri Moghadder Mohsen Safari 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第2期318-328,共11页
Engineering rock mass classification,based on empirical relations between rock mass parameters and engineering applications,is commonly used in rock engineering and forms the basis for designing rock structures.The ba... Engineering rock mass classification,based on empirical relations between rock mass parameters and engineering applications,is commonly used in rock engineering and forms the basis for designing rock structures.The basic data required may be obtained from visual observation and laboratory or field tests.However,owing to the discontinuous and variable nature of rock masses,it is difficult for rock engineers to directly obtain the specific design parameters needed.As an alternative,the use of geophysical methods in geomechanics such as seismography may largely address this problem.In this study,25 seismic profiles with the total length of 543 m have been scanned to determine the geomechanical properties of the rock mass in blocks Ⅰ,Ⅲ and Ⅳ-2 of the Choghart iron mine.Moreover,rock joint measurements and sampling for laboratory tests were conducted.The results show that the rock mass rating(RMR) and Q values have a close relation with P-wave velocity parameters,including P-wave velocity in field(V;).P-wave velocity in the laboratory(V;) and the ratio of V;V;(i.e.K;= V;/V;.However,Q value,totally,has greater correlation coefficient and less error than the RMR,In addition,rock mass parameters including rock quality designation(RQD),uniaxial compressive strength(UCS),joint roughness coefficient(JRC) and Schmidt number(RN) show close relationship with P-wave velocity.An equation based on these parameters was obtained to estimate the P-wave velocity in the rock mass with a correlation coefficient of 91%.The velocities in two orthogonal directions and the results of joint study show that the wave velocity anisotropy in rock mass may be used as an efficient tool to assess the strong and weak directions in rock mass. 展开更多
关键词 Rock mass classification P-wave velocity Q system Rock mass rating(RMR) Geophysical methods
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Synthesis of clay-supported nanoscale zero-valent iron using green tea extract for the removal of phosphorus from aqueous solutions 被引量:6
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作者 Akbar Soliemanzadeh Majid Fekri 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第7期924-930,共7页
This study addresses the synthesis of nanoscale zero-valent iron(n ZVI) in the presence of natural bentonite(B-n ZVI) using green tea extract. The natural bentonite and B-n ZVI were then applied for the removal of pho... This study addresses the synthesis of nanoscale zero-valent iron(n ZVI) in the presence of natural bentonite(B-n ZVI) using green tea extract. The natural bentonite and B-n ZVI were then applied for the removal of phosphorus from aqueous solutions at various concentrations, p H levels and contact time. The desorption of phosphorus(P) from adsorbents was done immediately after sorption at the maximum initial concentration using the successive dilution method. The characterization of FTIR, SEM, and XRD indicated that n ZVI was successfully loaded to the surface of natural bentonite. The sorption of phosphorus on B-n ZVI was observed to be p H-dependent, with maximum phosphorus removal occurring at the p H range of 2 to 5. The results demonstrate that the maximum sorption capacities of natural bentonite and B-n ZVI were 4.61 and 27.63 mg·g^(-1), respectively.Langmuir, Freundlich, and Redlich–Peterson models properly described the sorption isotherm data. For either adsorbent, desorption isotherms did not coincide with their corresponding sorption isotherms, suggesting the occurrence of irreversibility and hysteresis. The average percentages of retained phosphorus released from natural bentonite and B-n ZVI were 80% and 9%, respectively. The results indicated that sorption kinetics was best described by the pseudo-second-order model. The present study suggests that B-n ZVI could be used as a suitable adsorbent for the removal of phosphorus from aqueous solutions. 展开更多
关键词 Green tea Nano zero-valent iron Natural bentonite PHOSPHORUS SORPTION
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Electrodeposition and characterization of nanocrystalline Fe-Ni-Cr alloy coatings synthesized via pulse current method 被引量:5
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作者 Ebrahim YOUSEFI Ahmad IRANNEJAD Shahriar SHARAFI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第12期2591-2603,共13页
The nanocrystalline Fe-Ni-Cr coatings were electrodeposited by using the pulse current technique.The SEM results showed that the coatings had a mixed morphology of small nodules and fine cauliflower structures at low ... The nanocrystalline Fe-Ni-Cr coatings were electrodeposited by using the pulse current technique.The SEM results showed that the coatings had a mixed morphology of small nodules and fine cauliflower structures at low current densities.Also,the Cr content was increased at expense of Fe and Ni contents at high current densities.XRD patterns confirmed that the pulse current density had a positive effect on the grain refinement.The results of vibrating sample magnetometer(VSM)measurements demonstrated that by increasing the current density,the saturation magnetization was decreased and the coercivity was increased due to the enhancement of Cr content and the reduction of the grain size.The friction coefficient and wear rate values were decreased by increasing the pulse current density.Also,both the adhesive and abrasive wear mechanisms were observed on the worn surfaces.The abrasive grooves and the amount of wear debris were decreased by increasing the pulse current density. 展开更多
关键词 pulse electrodeposition current density nanocrystalline Fe-Ni-Cr coatings magnetic behavior tribological properties
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An ANN-based approach to predict blast-induced ground vibration of Gol-E-Gohar iron ore mine,Iran 被引量:8
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作者 Mahdi Saadat Manoj Khandelwal M.Monjezi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第1期67-76,共10页
Blast-induced ground vibration is one of the inevitable outcomes of blasting in mining projects and may cause substantial damage to rock mass as well as nearby structures and human beings.In this paper,an attempt has ... Blast-induced ground vibration is one of the inevitable outcomes of blasting in mining projects and may cause substantial damage to rock mass as well as nearby structures and human beings.In this paper,an attempt has been made to present an application of artificial neural network(ANN)to predict the blast-induced ground vibration of the Gol-E-Gohar(GEG)iron mine,Iran.A four-layer feed-forward back propagation multi-layer perceptron(MLP)was used and trained with Levenberg–Marquardt algorithm.To construct ANN models,the maximum charge per delay,distance from blasting face to monitoring point,stemming and hole depth were taken as inputs,whereas peak particle velocity(PPV)was considered as an output parameter.A database consisting of69data sets recorded at strategic and vulnerable locations of GEG iron mine was used to train and test the generalization capability of ANN models.Coefficient of determination(R2)and mean square error(MSE)were chosen as the indicators of the performance of the networks.A network with architecture4-11-5-1and R2of0.957and MSE of0.000722was found to be optimum.To demonstrate the supremacy of ANN approach,the same69data sets were used for the prediction of PPV with four common empirical models as well as multiple linear regression(MLR)analysis.The results revealed that the proposed ANN approach performs better than empirical and MLR models. 展开更多
关键词 Blast-induced ground vibration Empirical predictors Artificial neural network(ANN) Multiple linear regression
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Isothermal kinetics of mechanochemically and thermally synthesized Ag from Ag_2O 被引量:6
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作者 Gholam Reza KHAYATI Kamal JANGHORBAN Mohamad Hosein SHARIAT 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期935-942,共8页
The kinetics of isothermal reduction of Ag2O with graphite under argon atmosphere for a non-activated sample and mechanically activated sample was investigated.It is found that Johnson-Mehl-Avrami model appropriately ... The kinetics of isothermal reduction of Ag2O with graphite under argon atmosphere for a non-activated sample and mechanically activated sample was investigated.It is found that Johnson-Mehl-Avrami model appropriately explained the thermal and mechanochemical synthesis of Ag from Ag2O+ghraphite mixture.The process kinetics was investigated using the same approach for milled and unmilled samples.The results show that the Avrami exponent of mechanochemical reduction is higher than that of high temperature thermal reduction.Also,the mechanisms of nuclei growth in thermal and mechanochemical reduction are diffusion controlled and interface controlled,respectively. 展开更多
关键词 isothermal kinetics mechanochemical activation thermal reduction Johnson-Mehl-Avrami model AG
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Application of numerical modeling and genetic programming to estimate rock mass modulus of deformation 被引量:5
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作者 Ebrahim Ghotbi Ravandi Reza Rahmannejad +1 位作者 Amir Ehsan Feili Monfared Esmaeil Ghotbi Ravandi 《International Journal of Mining Science and Technology》 SCIE EI 2013年第5期733-737,共5页
Estimation of the rock mass modulus of deformation(Em)is one of the most important design parameters in designing many structures in and on rock.This parameter can be obtained by in situ tests,empirical relations betw... Estimation of the rock mass modulus of deformation(Em)is one of the most important design parameters in designing many structures in and on rock.This parameter can be obtained by in situ tests,empirical relations between deformation modulus and rock mass classifcation,and estimating from laboratory tests results.In this paper,a back analysis calculation is performed to present an equation for estimation of the rock mass modulus of deformation using genetic programming(GP)and numerical modeling.A database of 40,960 datasets,including vertical stress(rz),horizontal to vertical stresses ratio(k),Poisson’s ratio(m),radius of circular tunnel(r)and wall displacement of circular tunnel on the horizontal diameter(d)for input parameters and modulus of deformation for output,was established.The selected parameters are easy to determine and rock mass modulus of deformation can be obtained from instrumentation data of any size circular galleries.The resulting RMSE of 0.86 and correlation coeffcient of97%of the proposed equation demonstrated the capability of the computer program(CP)generated by GP. 展开更多
关键词 Modulus of deformation(Em) DISPLACEMENT Numerical modeling Genetic programming(GP) Back analysis
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Correlation of Shear Viscosity of Nanofluids Using the Local Composition Theory 被引量:5
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作者 M.S. Hosseini A. Mohebbi S Ghader 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第1期102-107,共6页
In this study,a new method is presented to correlate the shear viscosity of nanofluids by local composition theory.The Eyring theory and nonrandom two-liquid(NRTL)equation are used for this purpose.The effects of temp... In this study,a new method is presented to correlate the shear viscosity of nanofluids by local composition theory.The Eyring theory and nonrandom two-liquid(NRTL)equation are used for this purpose.The effects of temperature and particle volume concentration on the viscosity are investigated.The adjustable parameters of NRTL equation are obtained by fitting with experimental data.The calculated shear viscosities for nanofluids of CuO/water with 29 nm particle size,Al2O3/water with two different particle diameters,36 nm and 47 nm,and CuO/(ethylene glycol,water)are compared with experimental data and the average absolute deviation(AAD)is 1.2%,while the results from some conventional models yield an AAD of 190%.The results of this study are in excellent agreement with experimental data. 展开更多
关键词 NANOFLUID VISCOSITY local composition theory nonrandom two-liquid equation Eyring theory
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Adsorption behavior of Sb(Ⅲ) in single and binary Sb(Ⅲ)-Fe(Ⅱ) systems on cationic ion exchange resin: Adsorption equilibrium, kinetic and thermodynamic aspects 被引量:6
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作者 F.MOGHIMI A.H.JAFARI +1 位作者 H.YOOZBASHIZADEH M.ASKARI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第1期236-248,共13页
The present study dealt with the mechanism of competitive adsorption of Sb(Ⅲ)and Fe(Ⅱ)ions from a copper-containing aqueous solution on Purolite S957,a commercially available cationic ion-exchange adsorbent.Experime... The present study dealt with the mechanism of competitive adsorption of Sb(Ⅲ)and Fe(Ⅱ)ions from a copper-containing aqueous solution on Purolite S957,a commercially available cationic ion-exchange adsorbent.Experiments were conducted using aqueous copper sulfate solutions containing either single or conjoint ions,using both sedentary and batch adsorption techniques to ascertain the sensitivity of the adsorption process to variation in p H,mass of resin,contact time,and temperature as well as establishing the optimal range of variables for maximum ion removal.The data from single ion adsorption tests were fitted by non-linear regression techniques to Henry,Langmuir,Freundlich,Temkin,and Dubinin–Radushkevich isotherm models.Freundlich isotherm for Sb(Ⅲ)and Freundlich and Henry models for Fe(Ⅱ)solutions best express the adsorption equilibrium data;while for binary ion electrolytes,the extended Freundlich model fitted the data satisfactorily.The kinetic model adequately describing adsorption was shown to be the pseudo-first-order,underscoring the dominant role of physical adsorption playing in the process.Thermodynamic parameters for the adsorption process reveal differences in the Sb(Ⅲ)adsorption mechanism from single ion and Sb(Ⅲ)-Fe(Ⅱ)containing electrolytes.The adsorption of Sb(Ⅲ)alone is endothermic,whereas the process becomes exothermic in the Sb(Ⅲ)-Fe(Ⅱ)system. 展开更多
关键词 Sb(Ⅲ) ion exchange copper refining THERMODYNAMICS kinetics Purolite adsorbent
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A new analytical solution for calculation the displacement and shear stress of fully grouted rock bolts and numerical verifications 被引量:8
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作者 Ghadimi Mostafa Shariar Koroush Jalalifar Hossein 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1073-1079,共7页
In presence of difficult conditions in coal mining roadways, an adequate stabilization of the excavation boundary is required to ensure a safe progress of the construction. The stabilization of the roadways can be imp... In presence of difficult conditions in coal mining roadways, an adequate stabilization of the excavation boundary is required to ensure a safe progress of the construction. The stabilization of the roadways can be improved by fully grouted rock bolt, offering properties optimal to the purpose and versatility in use. Investigations of load transfer between the bolt and grout indicate that the bolt profile shape and spacing play an important role in improving the shear strength between the bolt and the surrounding strata. This study proposes a new analytical solution for calculation displacement and shear stress in a fully encapsulated rock bolt in jointed rocks. The main characteristics of the analytical solution consider the bolt profile and jump plane under pull test conditions. The performance of the proposed analytical solution, for three types of different bolt profile configurations, is validated by ANSYS software. The results show there is a good agreement between analytical and numerical methods. Studies indicate that the rate of displacement and shear stress from the bolt to the rock exponentially decayed. This exponential reduction in displacement and shear stress are dependent on the bolt characteristics such as: rib height, rib spacing, rib width and grout thickness, material and joint properties. 展开更多
关键词 Fully grouted bolt Jointed rock DISPLACEMENT Shear stress
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