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Chemical Research in Chinese Universities 2010年第6期26卷 893-898页

作者： WASEEM Amir yaqoob mohammad NABI Abdul Department of Chemistry COMSATS Institute of Information Technology Department of Chemistry University of Balochistan

A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe（Ⅲ）/ferricyanide,the in situ reduced ions are reacted with unreduced portion of ferricyanide/Fe（Ⅲ） to form soluble Prussian blue,which is monitored at 735 *** calibration graphs are linear in the concentration ranges of（1―100）×10-6 mol/L for cysteine and N-acetyl cysteine,and（1―50）×10-6 mol/L for *** relative standard deviations of 1.8%,2.5% and 1.9% were found for eleven replicate analyses of 5×10-6 mol/L cysteine,N-acetyl cysteine and *** limits of detection（3σ blank） at 5×10-7 mol/L for cysteine,and 3×10-7 mol/L for N-acetyl cysteine and glutathione were *** proposed method allowed 60 injections/*** effects of common substances present in pharmaceuticals and human physiological fluids were *** method was applied to determining cysteine in pharmaceutical formulations with the recoveries in a range of 97% to 106% and the results obtained are agreed well with labeled values.

关键词： Flow injection Spectrophotometry Cysteine Prussian blue Fe(Ⅲ) Ferricyanide Pharmaceutical

Chemiluminescent Determination of Cyromazine in Milk Samples Using Copper（III） Chelate-Triton X-100 by Flow Injection Analysis

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Chemical Research in Chinese Universities 2017年第3期33卷 354-359页

作者： Muhammad ASGHAR mohammad yaqoob Abdul NABI Department of Chemistry University of Baloehistan Quetta 87300 Pakistan

Cyromazine（CYR） was determined in milk samples using copper（HI） chelate-Triton X-100 chemiluminescence（CL） system associated with flow-injection（FI） in KOH medium. The relative CL intensity for CYR concentration was linear over the range of 5×10^-4-10μg/mL（R2=0.9990, n=11） with injection rate of 160 h-1 and the relative standard deviation（RSD, n=4） of 1.2%-2.6%. The limit of detection（LOD） for signal-to-noise ratio of 3 was 1.5×10^4μg/mL. The influences of key chemical and physical parameters, some major fresh water ions at their maximum admissible concentrations and a number of pesticides were examined as potential interferences. The concentrations of CYR in spiked milk samples were successfully determined by the proposed method and the results were in good agreement with that of the previously reported HPLC method, having recovery range of （92% a=4%）-（106% a：2%）. The possible CL reaction mechanism for copper（m） chelate-Triton X-100-CYR was also briefly discussed.

关键词： Chemiluminescence Flow injection analysis Cyromazine Milk sample

Flow injection spectrophotometric determination of vitamin E in pharmaceuticals,milk powder and blood serum using potassium ferricyanide-Fe(Ⅲ) detection system

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Chinese Chemical Letters 2010年第6期21卷 712-715页

作者： Saima Jadoon Amir Waseem mohammad yaqoob Abdul Nabi Department of Chemistry University of BalochistanQuettaPakistan

A simple and sensitive flow injection spectrophotometric method is reported for the determination of vitamin E using potassium ferricyanide-Fe(Ⅲ) detection *** the presence of vitamin E,Fe(Ⅲ)/ferricyanide *** in situ reduced ions are then reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to make soluble Prussian blue,which is monitored at absorption wavelength of 735 *** calibration graph was obtained in the concentration range of 0.1-40μg mL^(-1).The relative standard deviations (n=4) were in the range of 1.1-3.6%,with limits of detection(3 s blank) of 0.04μg mL^(-1).The proposed method allowed 12 injections h^(-1).The method is applied to determine vitamin E in pharmaceuticals,infant milk and blood serum samples using hexane extraction with the recoveries in the range of 93±3 to 97.5±4%.The method is validated using certified reference materials SRM 968c for blood serum samples.

关键词： Flow injection Spectrophotometry Vitamin E Prussian blue Fe(III) Ferricyanide Pharmaceuticals Blood serum

Flow-injection Spectrophotometric Determination of Uric Acid in Urine via Prussian Blue Reaction

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Chemical Research in Chinese Universities 2011年第6期27卷 929-933页

作者： WASEEM Amir yaqoob mohammad NABI Abdul MURTAZA Ghulam HUSSAIN Izhar Department of Chemistry COMSATS Institute of Information Technology Department of Chemistry University of Balochistan Department of Pharmacy COMSATS Institute of Information Technology

A simple and sensitive flow injection（FI） spectrophotometric method was reported for the determination of uric acid based on the reduction of Fe（III）/ferricyanide in the presence of uric acid. The in situ reduced ions reacted with unreduced portion of ferricyanide/Fe（III） to form soluble Prussian blue, which was monitored at an absorption wavelength of 735 nm. The optimized conditions allow a linear calibration graph in a concentration range of 1―100 μmol/L. The relative standard deviation was in a range of 0.5%―2.5%, with a detection limit（3σ blank） of 0.3 μmol/L and a sampling frequency of 60 injection/h was obtained. The effect of common substances present in human physiological fluids on the determination of uric acid was examined. The method was applied to determining uric acid in human urine samples with the recoveries in a range of 96%―105%. The results agree well with those by spectrophotometric reference method at a confidence level of 95%. Spectrophotometric procedures for uric acid determination in clinical samples were reviewed briefly.

关键词： Flow injection analysis Spectrophotometry Uric acid Prussian blue Urine

Auto-tuning PVT data using multi-objective optimization: Application of NSGA-Ⅱ algorithm

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Petroleum 2024年第1期10卷 135-149页

作者： Abdolhadi Zarifi mohammad Madani mohammad Jafarzadegan Reservoir Engineering Systems Petroleum Engineering Department Main Office Building of National Iranian South Oil Company (NISOC) Combined Planning Management National Iranian Oil Company (NIOC) Reservoir Engineering Division Petroleum Engineering Department Petroleum Engineering and Development Company (PEDEC)

Reservoir simulation is known as perhaps the most widely used, accurate, and reliable method for field development in the petroleum industry. An integral part of a reliable reservoir simulation process is to consider robust and rigorous tuned EOS models. Traditionally, EOS models are tuned iteratively through arduous workflows against experimental PVT data. However, this comes with a number of drawbacks such as forcingly using weight factors, which upon alteration adversely affects the optimization *** objective of the current work is thus to introduce an auto-tune PVT matching tool using NSGA-II multi-objective optimization. In order to illustrate the robustness of the presented technique, three different PVT samples are used, including two black-oil and one gas condensate sample. We utilize PengRobinson EOS during all the manual and auto-tuning processes. Comparison of auto-tuned EOS-generated results with those of experimental and computed statistical error values for these samples clearly show that the proposed method is robust. In addition, the proposed method, contrary to the manual matching process, provides the engineer with several matched solutions, which allows them to select a match based on the engineering background to be best amenable to the problem at hand. In addition, the proposed technique is fast, and can output several solutions within less time compared to the traditional manual matching method.

关键词： Auto-tuning PVT Equation of state NSGA-II Multi-objective optimization

Investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： mohammad Taghipoor Abolfazl Hassani mohammad M.Karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SFP)mixture in accordance with the engineering and mechanical *** study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)*** analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(ITS),and permeability tests were ***,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were *** the final stage,SFP was compared to HMA in terms of engineering characteristics and *** to the results,SFP was more resistant to skid,rutting,fire,and moisture damage,while HMA had a better performance in fracture tests,including SCB *** to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,***,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the ***,SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt

Recent Progress in Bionic Hydrogels for Articular Cartilage:Tribological and Mechanical Characteristics

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Journal of Bionic Engineering 2024年第2期21卷 653-673页

作者： mohammad Javan Almasi Dangsheng Xiong School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China

Cartilage regeneration and repair are considered clinical challenges since cartilage has limited capability for *** tissue-engineered materials have the ability to repair cartilage,they have weak mechanical characteristics and cannot resist long-term *** the other hand,surgery to replace the joint is frequently done to treat significant cartilage deterioration these ***,the materials that are being used for replacement have high friction coefficients,lack shock absorption functions,and lack *** research on natural articular cartilage structure and function may lead to bionic hydrogels,which have suitable physicochemical and biological characteristics(e.g.,tribological and mechanical properties and the ability to support loadbearing capability),but need *** on their tribological and mechanical characteristics,the current review highlights the most recent advancements of bionic hydrogels used for articular cartilage,highlighting both the field's recent progress and its potential for future *** this reason,firstly,some important property improvement methods of bionic hydrogels are discussed and then,the recent findings of various research on the making of those bionic materials are provided and *** seems that by using some modifications such as product design,surface treatments,animal tests,controlling the isoelectric point of hydrogels,and computer simulation,the intended mechanical and tribological characteristics of natural articular cartilage may be attained by the bionic hydrogels.

关键词： Bionic hydrogel Articular cartilage Mechanical property Tribological property Lubrication

Ultrasensitive plasmonic sensor based on MDM waveguide containing Persian Orsi window cavities for refractive index and blood plasma sensing

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Optoelectronics Letters 2024年第7期20卷 406-411页

作者： mohammad Ghanavati mohammad Azim Karami School of Electrical Engineering Iran University of Science and Technology

We developed a plasmonic refractive index（RI） with a metal-dielectric-metal（MDM） structure that utilizes two Persian Orsi windows-like separated cavities with a high figure of merit（FoM） and ultrasensitivity. The simulated and optimized Ag-air-Ag MDM sensor for surface plasmon resonance（SPR） offers high RI sensitivity（SRI） and the ability to detect blood plasma concentration（BPC）. The results verified that structural parameters have an effect on S;RI;, full width at half maximum（FWHM）, FoM, sensitivity of blood plasma（S;p;） for right and left peaks, whose values are 1 345.45 nm·RIU;-1;, 32 nm, 42.04 RIU;-1;, 0.26 and 0.19 nm·L·g;-1;, respectively. The proposed design opens a new horizon in sensor development.

关键词： A

The modeling non-sequential double ionization of helium atom under highintensity femtosecond laser pulses with shielding charge approximation

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Communications in Theoretical Physics 2024年第2期76卷 151-156页

作者： Marjan Zakavi mohammad Sabaeian Department of Physics Faculty of ScienceShahid Chamran University of AhvazIran Center for Research on Laser and Plasma Shahid Chamran University of AhvazIran

In this study,we successfully extracted the‘knee structure’for non-sequential double ionization(NSDI)in the helium *** achieve this,for the first time,we solved the time-dependent Schrödinger equation in three dimensions for the helium atom,utilizing the shielding charge *** findings corroborate prior observations by Wang et al[Wang and Eberly,***.105,083001(2010)],demonstrating that NSDI occurs within a narrower time window in circular polarization compared to linear *** a result,the yield of linear polarization was higher than that of circular polarization,aligning with the previously reported ***,in the case of circular polarization,the time window further narrows with increasing intensity,attributed to a decrease in the time-of-flight.

关键词： NSDI knee structure TDSE shielding charge helium 3D-TDSE

Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： mohammad Saifullah Vinay K.Gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model