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Application of graphite screen printed electrode modified with dysprosium tungstate nanoparticles in voltammetric determination of epinephrine in the presence of acetylcholine

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Journal of Rare Earths 2018年第7期36卷 750-757页

作者： Hadi Beitollahi Zahra Dourandish Somayeh Tajik Mohammad Reza Ganjali parviz norouzi Farnoush Faridbod Environment Department Irtstitute of Science and High Technology and Environmental SciencesGraduate University of Advanced Technology Department of Chemistry Graduate University of Advanced Technology NanoBioElectrochemistry Research Center Bam University of Medical Scicnce Center of Excellence in Electrochemistry Faculty of ChemistryUniversity of Tehran Biosensor Research Center Endocrinology & Metabolism Molecular-Cellular Sciences InstituteTehran University of Medical Sciences

The current work focuses on the development of a sensitive and selective electrochemical device based on a graphite screen printed electrode modified with Dy2（WO4）3 nanoparticles（DWO/SPE） for the analysis of epinephrine in samples also containing acetylcholine. The study proves that the sensor has excellent electron-mediating behavior in the oxidation of epinephrine in a 0.1 mol/L phosphate buffer solution（PBS）（pH 7.0）. The application of the DWO/SPE in differential pulse voltammetry（DPV） is found to lead to distinct response for the oxidation of epinephrine and acetylcholine, with the potentials of the epinephrine and acetylcholine peaks（△Ep） to be 550 mV apart. The detection limits of the method for epinephrine and acetylcholine are 0.5 and 0.7 μmol/L（S/N = 3） and the responses are found to be linear in the concentration ranges of 1.0-900.0 μmol/L and 1.0-1200.0 μmol/L in a PBS buffer（pH = 7.0）respectively. The modified electrode was used for the detection of epinephrine and acetylcholine in real samples and found to produce satisfactory results. These results can be a proof that Dy2（WO4）3 nanoparticles can find promising applications in electrochemical sensors to be used for the analysis of（bio）chemical species.

关键词： Epinephrine Acetylcholine Dy2(WO4)3 nanoparticles Graphite screen printed electrode Rare earths

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Performance characteristics of the airlift pump under vertical solid-water-gas flow conditions for conveying centimetric-sized coal particles

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International Journal of Coal Science & Technology 2024年第2期11卷 53-66页

作者： parviz Enany Carsten Drebenshtedt Faculty of Mining and Special Civil Engineering Technische Universitat BergakademieGustav-Zeuner StraBe 1A09599FreibergGermany

In this study,the installation of an airlift pump with inner diameter of 102 mm and length of 5.64 m was utilized to consider the conveying process of non-spherical coal particles with density of 1340 kg/m3 and graining 25-44.5 *** test results revealed that the magnitude of increase in the solid transport rate due to the changes in the three tested parameters between compressed air velocity,submergence ratio,and feeding coal possibility was not the same,which are stand in range of 20%,75%,and 40%,***,creating the optimal airlift pump performance is highly dependent on submergence *** importantly,we measured the solid volume fraction using the method of one-way valves in order to minimize the disadvantages of conventional devices,such as fast speed camera and conductivity ring *** results confirmed that the volume fraction of the solid phase in the transfer process was always less than 12%.To validate present experimental data,the existing empirical correlations together with the theoretical equations related to the multiphase flow was *** overall agreement between the theory and experimental solid delivery results was particularly good instead of the first stage of conveying *** drawback can be corrected by omitting the role of friction and shear stress at low air income *** was also found that the model developed by Kalenik failed to predict the performance of our airlift operation in terms of the mass flow rate of the coal particles.

关键词： Vertical velocity Non-spherical particle Submergence ratio Three-phase flow Churn flow Superficial velocity

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Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

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Frontiers of Structural and Civil Engineering 2020年第6期14卷 1359-1371页

作者： Mahdi FAKOOR Hadi parviz Faculty of New Sciences and Technologies University o f TehranTehran 14395-1561Iran

In this study,the influences of spatially varying stochastic properties on free vibration analysis of composite plates were investigated via development of a new approach named the deterministic-stochastic Galerkin-based semi-analytical *** material properties including tensile modulus,shear modulus,and density of the plate were assumed to be spatially varying and *** fields with first-order Markov kernels were utilized to define the aforementioned material *** stochastic fields were decomposed via application of the K arhunen-Loeve theorem.A first-order shear deformation theory was assumed,following which the displacement field was defined using admissible trigonometric modes to derive the potential and kinetic *** stochastic equations of motion of the plate were obtained using the variational *** deterministic-stochastic Galerkin-based method was utilized to find the probability space of natural frequencies,and the corresponding mode shapes of the plate were determined using a polynomial chaos *** proposed method significantly reduced the size of the mathematical models of the structure,which is very useful for enhancing the computational efficiency of stochastic *** methodology was verifed using a stochastic finite element method and the available results in *** sensitivity of natural frequencies and corresponding mode shapes due to the uncertainty of material properties was investigated,and the results indicated that the higher-order modes are more sensitive to uncertainty propagation in spatially varying properties.

关键词： composite plate spatially varying stochastic properties Galerkin method polynomial chaos approach semi-analytical approach

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Conceptual study of X-braced frames with different steel grades using cyclic half-scale tests

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 313-329页

作者： parviz Ebadi Saeid Sabouri-Ghomi Structural Engineering Khaje Nasir Toosi University of Technology

In this paper, an experimental and analytical study of two half-scale steel X-braced flames with equal nominal shear strength under cyclic loading is described. In these tests, all members except the braces are similar. The braces are made of various steel grades to monitor the effects of seismic excitation. Internal stiffeners are employed to limit the local buckling and increase the fracture life of the steel bracing. A heavy central core is introduced at the intersection of the braces to decrease their effective length. Recent seismic specifications are considered in the design of the X-braced frame members to verify their efficiency. The failure modes of the X-braced frames are also illustrated. It is observed that the energy dissipation capacity, ultimate load capacity and ductility of the system increase considerably by using lower grade steel and proposed detailing. Analytical modeling of the specimens using nonlinear finite element software supports the experimental findings.

关键词： bracing low grade steel experimentation cyclic test seismic behavior analytical modeling ductility

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Evaluation of ecological capability and land use planning for different uses of land with a new model of EMOLUP in Jahrom County,Iran

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Frontiers of Earth Science 2023年第2期17卷 561-575页

作者： parviz JOKAR Masoud MASOUDI Department of Natural Resources and Environmental Engineering School of AgricultureShiraz UniversityShiraz ***Iran

Land use planning is one of the basic principles of sustainable development in a region and in a *** main objective of this paper is to test a new model of land use planning in order to evaluate ecological suitability and prioritize different land uses in Jahrom County placed in Fars Province,*** two main steps were prepared for the new model of Eco-Socioeconomic Model of Land Use Planning(EMOLUP).Step 1 includes ecological capability evaluation of different land uses including forest,rangeland,agriculture,conservation,and *** step is composed of the geometric mean method instead of the Boolean method;and step 2 includes land use planning and prioritizing for the various uses mentioned *** step is composed of intersecting ecological capability maps and land use planning,based on two scenarios(economic and social).It was compared with qualitative and current quantitative ***,current land use is employed for calibrating and modifying the *** results of ecological suitability evaluation showed that the EMOLUP model has more accuracy in the process of comparison than other current ***,revised method using the geometric mean(with overall accuracy>72 and kappa index>0.55 for all land uses and rangeland with overall accuracy=32 and kappa index=0.02)is better than Boolean models,and the method of the calibrated geometric mean(with overall accuracy>87 and kappa index>0.73 for all land uses)is the best among different used *** should be noted that the arithmetic mean has the lowest accuracy(with overall accuracy<45 and kappa index<0.24 for all land uses).Also,the results of prioritizing and land use planning showed that the quantitative method with two socio-economic scenarios(result based on average of EPM erosion model=0.3 that means 30%of modification in whole study area land uses)is the best method for land use planning in the study area.

关键词： EMOLUP Model geomean Boolean prioritizing land use capability

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An efficient aerodynamic shape optimization of blended wing body UAV using multi-fidelity models

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Chinese Journal of Aeronautics 2018年第6期31卷 1165-1180页

作者： parviz MOHAMMAD ZADEH Mohsen SAYADI Faculty of New Sciences and Technologies University of Tehran

This paper presents a novel optimization technique for an efficient multi-fidelity model building approach to reduce computational costs for handling aerodynamic shape optimization based on high-fidelity simulation models. The wing aerodynamic shape optimization problem is solved by dividing optimization into three steps—modeling 3D（high-fidelity） and 2D（lowfidelity） models, building global meta-models from prominent instead of all variables, and determining robust optimizing shape associated with tuning local meta-models. The adaptive robust design optimization aims to modify the shape optimization process. The sufficient infilling strategy—known as adaptive uniform infilling strategy—determines search space dimensions based on the last optimization results or initial point. Following this, 3D model simulations are used to tune local meta-models. Finally, the global optimization gradient-based method—Adaptive Filter Sequential Quadratic Programing（AFSQP） is utilized to search the neighborhood for a probable optimum point. The effectiveness of the proposed method is investigated by applying it, along with conventional optimization approach-based meta-models, to a Blended Wing Body（BWB） Unmanned Aerial Vehicle（UAV）. The drag coefficient is defined as the objective function, which is subjected to minimum lift coefficient bounds and stability constraints. The simulation results indicate improvement in meta-model accuracy and reduction in computational time of the method introduced in this paper.

关键词： Adaptive filter sequential quadratic programing(AFSQP) Adaptive robust meta-model Aerodynamic shape optimization Blended wing body(BWB) Move limit strategy Unmanned aerial vehicle(UAV)

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Validation of targeted microsurgical spermatic cord denervation: comparison of outcomes to traditional complete microsurgical spermatic cord denervation

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Asian Journal of Andrology 2019年第4期21卷 319-323页

作者： parviz K Kavoussi Austin Fertility and Reproductive Medicine Austin TX 78746 USA

The aim of this study was to validate the effectiveness of targeted microsurgical spermatic cord denervation (MSCD) of the trifecta nerve complex in comparison to traditional full MSCD with complete skeletonization of the spermatic cord in men with chronic orchialgia. Retrospective chart review was performed by a single fellowship-trained microsurge on between 2011 and 2016. Patie nts had follow-ups at 6 weeks, 6 mon ths, and 1 year postoperatively. Thirty-nine men with chronic orchialgia un derwe nt full MSCD between 2011 and 2013. In July 2013, after the publication of an anatomic study with identification of Wallerian degeneration of the trifecta nerve complex in men with chronic orchialgia, the technique was changed to targeted MSCD. From July 2013 to March 2016, 43 men underwent targeted MSCD. When comparing the full MSCD group to the targeted MSCD group, there was no significant difference in resolution of pain (66.7% vs 69.8%, P = 0.88), no difference in partial relief of pain (17.9% vs 23.3%, P =0.55), and no difference in failure to respond rates (15.4% vs 7.0%, P= 0.22) between the two groups. There was no differenee in mean change of visual analog pain scale scores between the two groups (P= 0.27). Targeted MSCD had a shorter operative time (53 min vs 21 min, P = 0.0001). Targeted MSCD offers patients comparable outcomes to traditional full MSCD, with a shorter operative time, a less technically challenging surgery, and potentially less risk to cord structures which should be preserved.

关键词： denervation microsurgical neurolysis spermatic cord

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Validation of robot-assisted vasectomy reversal

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Asian Journal of Andrology 2015年第2期17卷 245-247,I0008页

作者： parviz K Kavoussi Department of Reproductive Urology Austin Fertility and Reproductive Medicine Austin Texas 78745 USA.

Vasectomy reversal （VR） has traditionally been performed with the operative microscope. Recently, robot assistance has been applied to VR. Retrospective chart review from a single VR center included men who underwent either robot-assisted VR （RAVR） or microsurgical VR （MVR） by a single fellowship trained microsurgeon between 2011 and 2013 and had a 6 weeks postoperative semen analysis. Fifty-two men who were interested in VR were counseled and given the option of RAVR versus MVR. Twenty-seven men elected to have MVR while 25 men elected RAVR. These included vasovasostomies and vasoepididymostomies in both groups, as well as redo VRs in men who had failed previous VR attempts by other surgeons. There was no statistically significant difference between the microsurgical group and the robot-assisted group, respectively, in overall patency rates （89% vs 92%）, 6 weeks post-VR mean sperm concentrations （28 million m1-1 vs 26 million m1-1） or total motile counts （29 million vs 30 million）, or mean operative times （141 min vs 150 min）. There was a statistically significant difference in anastomosis time （64 min vs 74 min）, however, clinically this only represented a 10 min longer anastomosis time in the early robotic experience, which was found to be decreasing as the case series continued. Transitioning from MVR to RAVR is feasible with comparable outcomes.

关键词： patency robot-assisted vasectomy reversal vasoepididymostomy vasovasostomy

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A New Self-Loading Locomotion Mechanism for Wall Climbing Robots Employing Biomimetic Adhesives

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Journal of Bionic Engineering 2013年第1期10卷 12-18页

作者： Amirpasha Peyvandi parviz Soroushian Jue Lu Department of Civil and Environmental Engineering Michigan State University 3546 Engineering Building E. Lansing M/48824-1226 USA Senior Scientist Technova Corporation 1926 Turner Street Lansing M148906 USA

A versatile locomotion mechanism is introduced and experimentally verified. This mechanism comprises four rectangular wheels （legs） with rotational phase difference which enables the application of pressure to each contacting surface for securing it to the surface using bio-inspired or pressure-sensitive adhesives. In this mechanism, the adhesives are applied to two rigid plates attached to each wheel via hinges incorporating torsional springs. The springs force the plates back to their original position after the contact with the surface is lost in the course of locomotion. The wheels are made of low-modulus elastomers, and the pressure applied during contact is controlled by the elastic modulus, geometry and phase difference of wheels. This reliable adhesion system does not rely upon gravity for adhering to surfaces, and provides the locomotion mechanism with the ability to climb walls and transition from horizontal to vertical surfaces.

关键词： biomimetics adhesives locomotion climbing robots gecko

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Experimental study of post-peak behavior of bimrocks with high rock block proportions

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Journal of Central South University 2014年第2期21卷 761-767页

作者： Mohammad Afifipour parviz Moarefvand Department of Mining and Metallurgy Engineering Amirkabir University of Technology

Design and construction of engineering structures in geomaterials with block-in-matrix texture(referred as bimrock) such as conglomerates,breccias and agglomerates are challenging tasks for *** dealing with these materials in important structures such as open pits with high walls and pillars of deep underground mines,understanding the complete stress-strain behavior,including post-peak region,is a formidable yet crucial engineering *** study the post-peak behavior of bimrocks,artificial specimens were fabricated with a mixture of rock blocks and a cementing *** the experiments were conducted under uniaxial compression using a servo-control testing *** results show that the specimens with the highest block proportion(around 90% by mass) showed a small decrease in stress with strain increment in the post-peak *** specimens with lower block proportions were characterized by an approximately steep fall in stress and following to residual *** on the study,it is inferred that all the artificial specimens undergo post-failure deformation and the type of post behavior depends on rock block proportions.

关键词： bimrocks uniaxial compression loading servo-control post-peak

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