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Gardaneh Salavat porphyry copper system: Is it about metal endowment or fertility of the porphyritic intrusion?

Acta Geochimica 2022年第3期41卷 496-514页

作者： Seyyed reza Mashhadi Department of Geoscience Aarhus UniversityHøeghGuldbergs Gade 28000 Aarhus CDenmark

Gardaneh Salavat porphyry copper system is located in the northwest of Iran. It comprises a quartz diorite to diorite porphyritic intrusion that created extensive alteration haloes in the host rocks. Despite all technical considerations, the exploration activities did not yield to ore discovery. As the matter of fact, all of the geological,geophysical, and geochemical characteristics of a porphyry Cu-Au deposit exist but there is no economic mineralization. Detailed examinations suggest that the only reasonable explanation can be related to the infertility or low metal endowment of the porphyritic intrusion. The reasons include(1) anomalous ranges of Cu, Au, and Mo rather than economic ore grades,(2) weakly development of potassic alteration,(3) probably sulfur saturation of magma that occurred before intrusion emplacement in the host rocks, and(4) probably low metal endowment in the regional scale and the lack of known porphyry copper deposits in close neighborhoods. It is tried to test the proposed hypothesis with the introduced fertility indicators based on major and trace element geochemistry. However,current fertility indicators could not prove or reject the proposed hypothesis for Gardaneh Salavat porphyritic intrusion because of the high-K calc-alkaline to shoshonitic nature of the intrusive rocks together with the unavailability of relatively fresh/unaltered samples. This case study is notable to examine because(1) it shows that characterization of fertile from barren intrusions seems to be as important as vectoring towards concealed porphyry copper deposits, especially while dealing with deep exploration targets that are associated with high financial risks, and(2) it highlights the inefficiencies and uncertainties in introduced magma fertility indicators for porphyry copper intrusions. As a result, it is of high importance to conduct an overarching investigation on other possible fertility indicators as a fundamental need for the future of the exploration

关键词： Porphyry Copper Fertility Metal endowment Barren intrusion

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Experimental and numerical analyses of pure copper during ECFE process as a novel severe plastic deformation method

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Progress in Natural Science:Materials International 2014年第1期24卷 68-74页

作者： M.ebrahimi F.Djavanroodi Department of Mechanical Engineering Iran University of Science and Technology Department of Mechanical Engineering Imperial College

In this paper,a new severe plastic deformation method called equal channel forward extrusion(ECFE) process has been proposed and investigated by experimental and numerical approaches on the commercial pure copper billets. The experimental results indicated that the magnitudes of yield strength,ultimate tensile strength and Vickers micro-hardness have been markedly improved from 114 MPa,204 MPa and68 HV as the annealed condition to 269 MPa,285 MPa and 126 HV after the fourth pass of ECFE process,respectively. In addition,scanning electron microscopy observation of the samples showed that the average grain size of the as-received state which is about 22 μm has been reduced to 1.4 μm after the final pass. The numerical investigation suggested that although one pass ECFE process fabricates material with the mean effective strain magnitude of about 1,the level of imposed effective plastic strain gradually diminishes from the circumference to the center of the deformed billet.

关键词： SPD ECFE Tensile test HV SEM Effective strain

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Investigation of a mutual interaction force at different pressure amplitudes in sulfuric acid

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Chinese Physics B 2011年第8期20卷 454-459页

作者： Nastaran rezaee Rasoul Sadighi-Bonabi Mona Mirheydari Homa ebrahimi Department of Physics Sharif University of Technology11365-91TehranIran Department of Physics Islamic Azad University Central Tehran BranchTehranIran

This paper investiages the secondary Bjerknes force for two oscillating bubbles in various pressure amplitudes in a concentration of 95% sulfuric acid. The equilibrium radii of the bubbles are assumed to be smaller than 10 μm at a frequency of 37 kHz in various strong driving acoustical fields around 2.0 bars （1 bar=10^5 Pa）. The secondary Bjerknes force is investigated in uncoupled and coupled states between the bubbles, with regard to the quasi-adiabatic model for the bubble interior. It finds that the value of the secondary Bjerknes force depends on the driven pressure of sulfuric acid and its amount would be increased by liquid pressure amplitude enhancement. The results show that the repulsion area of the interaction force would be increased by increasing the driven pressure because of nonlinear oscillation of bubbles.

关键词： multi-bubble sonoluminescence secondary Bjerknes force coupled and uncoupled state,nonlinear oscillation

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The reliability of the Australasian Triage Scale:a meta-analysis

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World Journal of Emergency Medicine 2015年第2期6卷 94-99页

作者： Mohsen ebrahimi Abbas Heydari reza Mazlom Amir Mirhaghi Department of Emergency Medicine Imam Reza HospitalMashhad University of Medical Sciences Evidence-Based Caring Research Center Department of Medical-Surgical NursingSchool of Nursing and MidwiferyMashhad University of Medical Sciences Department of Nursing Faculty of NursingNeyshabur University of Medical SciencesNeyshaburand Evidence-Based Caring Research Center Department of Medical-Surgical Nursing School of Nursing & MidwiferyMashhad University of Medical Sciences

BACKGROUND: Although the Australasian Triage Scale(ATS) has been developed two decades ago, its reliability has not been def ined; therefore, we present a meta-analyis of the reliability of the ATS in order to reveal to what extent the ATS is *** SOURCES: Electronic databases were searched to March 2014. The included studies were those that reported samples size, reliability coefficients, and adequate description of the ATS reliability assessment. The guidelines for reporting reliability and agreement studies(GRRAS) were used. Two reviewers independently examined abstracts and extracted data. The effect size was obtained by the z-transformation of reliability coefficients. Data were pooled with random-effects models, and meta-regression was done based on the method of moment's ***: Six studies were included in this study at last. Pooled coefficient for the ATS was substantial 0.428(95%CI 0.340–0.509). The rate of mis-triage was less than fifty percent. The agreement upon the adult version is higher than the pediatric ***: The ATS has shown an acceptable level of overall reliability in the emergency department, but it needs more development to reach an almost perfect agreement.

关键词： Triage Emergency treatment Algorithm Reliability and validity Meta-analysis

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TCF7L2-rs7903146 polymorphism modulates the effect of artichoke leaf extract supplementation on insulin resistance in metabolic syndrome:a randomized,double-blind,placebo-controlled trial

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Journal of Integrative Medicine 2018年第5期16卷 329-334页

作者： Mehranghiz ebrahimi-Mameghani Mohammad Asghari-Jafarabadi Khatereh rezazadeh Nutrition Research Center School of Nutrition & Food Sciences Tabriz University of Medical Sciences Tabriz *** lran Road Traffic Injury Research Center Tabriz University of Medical Sciences Tabriz *** Iran Department of Statistics and Epidemiology School of Health Tabriz University of Medical Sciences Tabriz *** Iron Student Research Committee School of Nutrition & Food Sciences Tabriz University of Medical Sciences Tabriz Iran

Background： Transcription factor 7-like 2 （TCF7L2）-rs7903146 polymorphism is associated with increased risk of type 2 diabetes. The response of insulin and insulin resistance to artichoke leaf extract （ALE） may be affected by TCF7L2-rs7903146 polymorphism. Objective： This study examined the effects of ALE supplementation on metabolic parameters of the TCF7L2-rs7903146 polymorphism in patients with metabolic syndrome （MetS）. Design, setting, participants and interventions： This double-blind clinical trial was conducted on 80 patients with MetS in Sina Clinic, Khoy, Iran. The patients were randomized into ALE or placebo groups to receive either ALE （1800 mg/d as four tablets） or matching placebo for 12 weeks. Main outcome rneasures： Anthropometric indices, blood pressure, glucose and lipid profile levels were measured before and after the study. Moreover, patients were genotyped for TCF7L2 polymorphism. Results： ALE supplementation decreased insulin level and the homeostasis model assessment of insulin resistance （HOMA-IR） in patients with the ＂IT genotype of TCF7L2-rs7903146 polymorphism （P 〈 0.05）. There was no significant interaction between blood pressure, glucose and lipid profile response to ALE supplementation. Conclusion： The responses of insulin and HOMA-lR to ALE supplementation have shown an interaction with single-nucleotide polymorphism rs7903146 in TCF7L2. Trial registration： Iranian Registry of Clinical Trial IRCT201409033320N9.

关键词： Metabolic syndrome Artichoke leaf extract Transcription factor 7-like 2 Insulin Insulin resistance Alternative and complementary medicine Diabetes

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Evaluation of attraction terms in equations of state on the prediction of solubility of some biomolecules in supercritical carbon dioxide

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Chinese Chemical Letters 2009年第4期20卷 501-505页

作者： Mohammad reza Bozorgmehr Mohammad reza Housaindokht Department of Chemistry Faculty of Science.Islamic Azad UniversityMashad BranchMashhadIran Department of Chemistry Faculty of ScienceFerdowsi University of MashhadMashadIran

In the present work, effect of the attraction terms of four recently modified Peng-Robinson （MPR） equations of state on the prediction of solubility of caffeine, cholesterol, uracil and erythromycin was studied. The attraction terms of two of these equations are linear relative to the acentric factor and for the other two are exponential. It is found that the later show less deviation. Also interaction parameters for the studied systems are obtained and the percentage of average absolute relative deviation （%AARD） in each calculation is displayed.

关键词： Equation of state Solubility Supercritical carbon dioxide Biomolecules

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Microstructure and impact behavior of Mg-4Al-5RE-xGd cast magnesium alloys

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Journal of Magnesium and Alloys 2024年第5期12卷 1799-1814页

作者： Jie Wei Qudong Wang Huisheng Cai Mahmoud ebrahimi Chuan Lei National Engineering Research Center of Light Alloy Net Forming and Key State Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This work investigated the microstructure and impact behavior of Mg-4Al-5RE-xGd(RE represents La-Ce mischmetal;x=0,0.2,0.7 wt.%)alloys cast by high-pressure die casting(HPDC),permanent mold casting(PMC),and sand casting(SC)*** results indicated that with increasing Gd content,the grain sizes of the HPDC alloy had a slight change,but the grains of the PMC and SC alloys were significantly ***,the acicular Al_(11)RE_(3)phase was modified into the short-rod shape under the three casting *** impact toughness of the studied alloy was mainly dominated by the absorbed energy during the crack *** increasing Gd content,the impact toughness of the studied alloy monotonically increased due to the lower tendency of the modified second phase toward crack *** impact stress was higher than the tensile stress,exhibiting a strain rate sensitivity for the mechanical response;however,the HPDC alloy had an inconsistent strain rate sensitivity during the impact event due to the transformation of the deformation mechanism from twinning to slip with increasing *** dimples covered the fracture surface of the fine-grained HPDC alloys,indicating a typical ductile ***,due to the deficient{1012}twinning activity and the suppressed grain boundary sliding during the impact event,the HPDC alloys showed insufficient plastic deformation capacity.

关键词： Mg-Al-RE alloy Gadolinium Microstructure Impact behavior

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Highly sensitive determination of promazine in pharmaceutical and biological samples using a ZnO nanoparticle-modified ionic liquid carbon paste electrode

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Chinese Chemical Letters 2016年第5期27卷 779-782页

作者： Vahid Arabali Mahmoud ebrahimi Hassan Karimi-Maleh Department of Chemistry Mashhad Branch Islamic Azad University Mashhad Iran Department of Chemistry Graduate University of Advanced Technology Kerman Iran

In this work we describe the first report for the determination of promazine using a nanostructure- modified ionic liquid carbon paste electrode in aqueous solutions. To achieve this goal, a novel modified carbon paste electrode using ZnO nanoparticles and l-methyl-3-butylimidazolium bromide as a binder （ZnO/NPs/ILs/CPE） was fabricated. The oxidation peak potential of promazine at the surface of the ZnO/ NPs/ILs/CPE appeared at 685 mV, which was about 65 mV lower than the oxidation potential at the surface of CPE under similar conditions. Also, the peak current was increased to about 4.0 times higher at the surface of ZnO/NPs/ILs/CPE compared to that of CPE. The linear response range and detection limit were found to be 0.08-450 and 0.04 μmol/L, respectively. The modified electrode was successfully used for the determination of promazine in real samples with satisfactory results.

关键词： Promazine ZnO nanoparticle Ionic liquid Modified electrode

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Reinforcement selection for deep and high-stress tunnels at preliminary design stages using ground demand and support capacity approach

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International Journal of Mining Science and Technology 2018年第4期28卷 571-580页

作者： reza Masoudi Mostafa Sharifzadeh Department of Mining&Metallurgical Engineering Curtin University Western Australian School of Mines(WASM)Perth 6102Australia

Underground mining is going to be deeper gradually because near surface resources are going to be depleted. Therefore, risk of seismic events in underground mines is escalating. Additionally, existence of the large ratio of horizontal to vertical stress, could be a potential reason for high-stress condition and occurrence of dynamic activities. Depending on various parameters such as the level of induced stress, rock properties, etc., ground demand changes and it is difficult to estimate. On the other hand,under seismic condition, energy dissipation and deformation capacity of supports is the most important factors, however, rock support performance factors in dynamic conditions are still under *** the knowledge of reinforcement behaviour and capacity, specifically that of the rockbolt as a primary element in seismic conditions, would help to develop a suitable, safe and economic support design. This paper contains various methods to estimate ground demand including the intact rock properties approach, failure thickness and ejection velocity estimation, and rockburst damage potential method. It also covers measurement methods of rockbolts energy dissipation capacities such as drop test,blasting simulating, back calculation and momentum transfer measurement methods. A large-scale dynamic test rig is also explained. Based on the findings, a table and a graph to show the applicable range of each type of rockbolts were presented. Suitable rockbolt types for various ground energy demand and deformation capacity range were categorised in the table and the graph. The presented support selection method facilitates the selection of a suitable reinforcement system at the preliminary stages of design and guides the designer to adjust the support reinforcement system based on observed ground and support reaction.

关键词： High-stress tunnels Support system Ground demand Reinforcement capacity Rockbolt

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Proportional integral derivative controller design using Legendre orthogonal functions

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Journal of Central South University 2016年第10期23卷 2616-2629页

作者： reza Moradi Mohammad Tabatabaei Department of Electrical Engineering Khomeinishahr Branch Islamic Azad University

The Legendre orthogonal functions are employed to design the family of PID controllers for a variety of plants. In the proposed method, the PID controller and the plant model are represented with their corresponding Legendre series. Matching the first three terms of the Legendre series of the loop gain with the desired one gives the PID controller parameters. The closed loop system stability conditions in terms of the Legendre basis function pole(λ) for a wide range of systems including the first order, second order, double integrator, first order plus dead time, and first order unstable plants are obtained. For first order and double integrator plants, the closed loop system stability is preserved for all values of λ and for the other plants, an appropriate range in terms of λ is obtained. The optimum value of λ to attain a minimum integral square error performance index in the presence of the control signal constraints is achieved. The numerical simulations demonstrate the benefits of the Legendre based PID controller.

关键词： PID controllers orthogonal functions legendre functions moment matching PI controller PD controller

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