Aqueous Solutions Of Copper Sulfate Research Articles

Green Synthesis of Copper Nanoparticles Using Leaf Extract of Phyllanthus niruri Lin. and Study of Its Antimicrobial Activity

Abstract: Nanoscience and Nanotechnology are the study and application of extremely small things and can be used across all the other science fields such as chemistry, biology, physics and engineering. Green synthesis of nanoparticles using plant extract is a promising and ecofriendly approach, often yielding particles with unique properties. The present study deals with biosynthesis, characterization and antimicrobial activity. Of copper sulphate nanoparticles using the leaf extract of Phyllanthus niruri. In this report, aqueous phase green synthesis of specifically copper sulphate nanoparticles using leaf extract (both fresh and dry leaf) aqueous leaf extract of leaf was used for the synthesis of nanoparticles. The synthesised nanoparticles of copper sulphate were confirmed by color change when 25ml of 1% aqueous copper sulphate solution was added to 5ml og plant extract. The synthesised nanoparticles were charecterised by UV-Visible spectroscopy, SEM (Scanning Electron Microscopy), and XRD (X-Ray Diffraction). The UV-VIS spectroscopy showed the absorption peak at 378nm for fresh leaf and 376nm for dry leaf. SEM was used to study the morphological features that was predominately spherical and aggregated into large structure with not welldefined morphology and the size347nm,358nm,400nm,457nm, for fresh leaf 1.13µm,1.14µm,771nm,935nm for dry leaf. XRD using this the particle size and nature of nanoparticle was found the average diameter of copper nanoparticles is 12.8nm for dry leaf and 6.10nm for fresh leaf. antimicrobial activity was done using different bacterial and fungal species, in antibacterial activity St. aureus show maximum inhibition that is 75% in fresh leaf and 63%in dry leaf while compare to others, S. typhi showed 0% inhibition it was not resistant towards P.niruri. In antifungal activity F.oxysporum has shown maximum inhibition that is 77% for both fresh and dry leaf, penicillium atramentosum showed 0% inhibition it was not resistant towards P.niruri

New Polynuclear Coordination Compounds Based on 2–(Carboxyphenyl)iminodiacetate Anion: Synthesis and X-rays Crystal Structures

In the present work, novel polymeric copper(II) coordination compounds, namely [Cu2(cpida)(H2O)4][Cu(cpida)]·3H2O (1) (cpida3− = 2-(carboxyphenyl)iminodiacetate anion) and Na[Cu(cpida)] (3), were synthesized and characterized using infrared spectroscopy, thermogravimetric analysis, elemental analysis, and single-crystal X-ray diffraction. Compound 1 was obtained by slowly evaporating an aqueous solution of H3cpida, copper(II) sulfate, and NaOH at room temperature. The structural characterization revealed that 1 is an ionic entity formed by the [Cu(cpida)]− anion and the [Cu2(cpida)(H2O)4]+ cation, both of polymeric 1D structure. Compound 3 was prepared under similar conditions from copper perchlorate and crystallized via acetone diffusion. It is a coordination polymer formed by the [Cu(cpida)]− units, and the sodium cation is present in the structure, counterbalancing the anion charge. Depending on the crystallization conditions, it was possible to obtain other solvation forms of these structures. Starting from the conditions of compound 1, via the diffusion of ethanol, [Cu2(cpida)(H2O)4][Cu(cpida)]·H2O·1/2EtOH (2) was precipitated, while a hydrate form of compound 3 with the formula Na[Cu(cpida)]·2H2O (4) was obtained via methanol diffusion.

Kinetic and in Situ Analysis for Ion Transport Process in Copper Electrodeposition Using Polyelectrolyte Membranes

Electrodeposition of metals has been one of the most important techniques for fabrication of microelectronics and semiconductor elements in printed circuit boards and electronics device manufacturing. From the industrial perspective, the management of electrodeposition bath is crucial to maintain product quality, productivity and long-term stability of the bath, the subject of which includes bath temperature, concentration of metal salts, supporting electrolytes, and various additives. Although these parameters have been optimized to achieve desirable deposition rate, depending on the product type and morphology, some environmental issues regarding with generating mist, sludges, and waste effluent during electrodeposition process are becoming apparent. Additionally, current electrodeposition process has been developed for substrates with large surface area and for large scale production of electronic components and could not be suitable for recent demand of small-lot, site-selective and multiproduct device microfabrication. Therefore, high-performance deposition system, allowing site-selective electrodeposition of metals without generation of large amount of effluents, needs to be developed to impact above environmental and cost perspectives. Recently, we reported a novel method for electrodeposition of metals using polyelectrolyte films attached on cathode substrate (solid electrodeposition: SED) [1]. The SED process enables one to deposit metals directly on the cathode surface from metal ions inside solid polyelectrolyte membranes and has desirable advantages including higher deposition rate, site-selectivity, and deposition using lower concentration electrolyte solution without additives. In this SED process, thin polyelectrolyte membrane sandwiched between electrodes effectively concentrates metal ions through interfacial penetration, which increases the conductance between the electrodes and realizes solid-state electrodeposition that produces no mist, sludge, or even waste effluent.In this study, we present mechanistic analysis of the SED process, including transport kinetics and equilibrium reaction of copper ions at solution/membrane interface (Figure A). We show that both detailed experimental results and theoretical calculations reveal that ion transfer in the present electrodeposition system is a penetration-controlled process at the solution/polyelectrolyte interface, providing an inherently different ion-transport mechanism compared to that of conventional diffusion-controlled electrodeposition. Several parameters including penetration rate constant, electrode geometry, and distance between polyelectrolyte and anode are varied to investigate the ion-transport process in the SED system. When the anode is slightly apart from polyelectrolyte film to introduce electrolyte layer but is closer as far as possible to it, greater current density for copper electrodeposition is achieved at steady state than that for the systemwhere the membrane is sandwiched by electrodes (Figure B). This can be due to maximum ion penetration rate and minimum resistivity of electrolyte layer, providing better deposition setup for high performance electrodeposition. Additionally, we also performed in situ analysis of concentration of copper ions inside polyelectrolyte film via visible absorption spectroscopy using a miscofiber during electrodeposition. As a result, concentration of copper in the polyelectrolyte film decreased initially and then became constant (steady state) as the deposition proceeded, a fashion of which was quite similar with that of current-time curves simultaneously acquired during constant-voltage electrodeposition.The developed deposition setup demonstrates stable electrodeposition of copper using aqueous copper sulfate solution with no supporting electrolytes and/or additives at deposition rate of few micrometers per minute. As a site-selective deposition tool, the SED process can be used to fabricate microelectronic and even semiconductor circuit elements in a manner that resembles stamping deposition, and is suitable for small-lot, on-demand, and multi-product microfabrication.Reference:[1] K. Akamatsu, S. Nakano, K. Kimura, Y. Takashima, T. Tsuruoka, H. Nawafune, Y. Sato, J. Murai, H. Yanagimoto, ACS Appl. Mater. Interfaces, 13 (2021) 13896-13906. Figure 1

Green Synthesis and Characterization of Copper Oxide Nanoparticles Using Tecoma Stans

Aims: An eco-friendly approach utilizing biologically-mediated processes has been developed for the fabrication of CuO nanoparticles using Tecoma stans leaves.
 Methodology: The synthesis of CuO nanoparticles was carried out using an environmentally friendly method, which involved the use of an aqueous solution of copper (II) sulfate and a leaf extract derived from Tecoma stans. The synthesized CuO nanoparticles were characterized using various instruments, including a UV-visible spectrophotometer, scanning electron microscopy, X-ray Diffraction Spectrometer, and Fourier-transform infrared spectroscopy.
 Results: The UV-Vis spectrum showed a characteristic absorption peak of CuO nanoparticles at 296 nm. The green-synthesized CuO nanoparticles were characterized using SEM, which revealed their morphological and structural characteristics and showed a mean particle size ranging from 20 nm to 200 nm. The FTIR spectrum, ranging from 584.63 cm-1 to 3430.41 cm-1, indicated the presence of various functional groups. X-ray powder diffraction (XRD) analysis confirmed the formation of monoclinic CuO with a crystalline nature, and an average particle size of 27.67 Å.
 Conclusion: The present study reports the development of a simple, low-cost, and biologically-mediated method for synthesizing CuO nanoparticles using an extract obtained from Tecoma stans leaves. The effectiveness of these nanoparticles can be evaluated through various biological activities, including antibacterial, antifungal, and cytotoxic assays.

OBTAINING OF A COMPOSITE COATING OF COPPER-MOLYBDENUM (VI) OXIDE WITH CATHODIC POLARIZATION

In this paper, considered the ways of obtaining a composite electrochemical coating by entering molybdenum (VI) oxide into the copper matrix in order to improve the physicochemical properties of the copper coating. The influence of electrochemical parameters (solution concentration, current density, concentration of molybdenum (VI) oxide) is investigated with cathodic polarization of a titanium electrode in aqueous solutions of copper sulfate. In the course of studies of the influence of the concentration of a dispersed particle that is part of a copper-molybdenum oxide (VI) composite, it was found that at high concentrations of dispersed particles in solution, the cathode surface is passivated and the optimal concentration of the dispersed component is determined. It was noted that with increasing current density, the amount of molybdenum (VI) oxide penetrating into the copper matrix increases slightly, these data were explained by the charge difference of the particles, as well as adsorption properties. As a result of the study, a compact composite coating on the cathode in a dispersed suspension of the composite in a solution of copper (II) sulfate was obtained. The results of the physico-chemical analysis of the resulting composite coating showed that 1.2% dispersed molybdenum (VI) oxide entered the copper matrix. As a result of tests of a composite coating made of copper-molybdenum oxide for chemical corrosion, it was found that this coating has high corrosion resistance from a copper coating obtained without molybdenum (VI) oxide. The surface roughness of the coating obtained on the cathode surface was observed in microphotographs. This was explained by the fact that molybdenum (VI) oxide penetrates into the copper matrix in the form of dispersed granules and forms a composite electrochemical shell with a copper coating.

Obtaining Films by Irradiation of an Aqueous Solution of Copper Sulfate by Infrared Laser Radiation

Obtaining Films by Irradiation of an Aqueous Solution of Copper Sulfate by Infrared Laser Radiation

Influence of cellulose-containing sorbent preparation method based on linen fiber on its functional properties

The creation of biosorbents based on modified flax fiber is aimed at solving the problem of water pollution from heavy metal ions. A method for obtaining a sorbent on the basis of linen fiber including sequential treatment of polysaccharide material with sodium metaperiodate and sodium bisulfite has been developed. Modification conditions for obtaining an effective sorbent have been selected. Equilibrium and kinetics of copper ions sorption with the use of native and modified linen fiber in comparison with Lewatit S100 cationic exchange resin have been studied. It is established that the time of achieving sorption equilibrium in the heterophase system 'aqueous solution of copper sulfate - a modified sorbent' is reduced by 1.5-2 times while the degree of extraction of copper ions is increased by about 1.5 times as compared to the initial fiber. The influence of solution pH on the sorption of copper ions by native flax fiber has been studied. It has been found that in the pH range of the medium 1-7, along with the sorption of Cu ions, the sorption of H ions is observed, which indicates a competitive mechanism of sorption of heavy metal cations and protons with the participation of the cellulose-containing sorbent. Experimental isotherms of copper ions sorption have been processed in linear coordinates of Langmuir's equation that made it possible to determine the values of maximum sorption capacity of sorbents under study which increase in a series: native flax fiber (0.86 mol/kg) < flax fiber, oxidized and treated with sodium bisulfite (1.69 mol/kg) < Lewatit S100 cationite (1.89 mol/kg). Data from infrared spectroscopy and elemental analysis indicate the appearance of new sorption-active groups in the sorbent structure. The sorbent has been tested for purification of aqueous solutions and beverages from heavy metal ions under laboratory conditions. Peculiarities of the sorption of copper (II) ions from juice and white wine have been revealed. It has been found that the obtained modified sorbent on the basis of flax fiber in the purification of beverages is not inferior to the industrial cationic exchange resins in its sorption properties.

Preparation of Films by Irradiation of a Copper Sulfate Aqueous Solution by Infrared Laser Radiation

The methodology, technique, and results of studies of the formation of films on the glass surface during laser irradiation of water solutions of copper sulfate with radiation are presented. The nanosecond radiation of an yttrium-aluminum garnet laser with a generation wavelength λ = 1.06 μm was used. Solutions with different concentrations of copper sulfate were applied. The structure of the films obtained in this case was compared with the structure of the films obtained as a result of drying solutions without exposure to laser radiation. The resulting films have both ordered and disordered structures. The characteristic dimensions of the structural elements of the films are 0.5–10 μm. The transmission of films in the visible spectral region (400–800 nm) was studied. In general, the resulting films are transparent in this area. Their transmission practically does not depend on the wavelength, but is different for different concentrations of the used solutions of copper sulfate.

Detailed velocity and heat transfer measurements of an advanced insert for impingement cooling

This work reports the results of paired experiments for the aft section of a complex internal cooling flow within a gas turbine vane using Magnetic Resonance Velocimetry (MRV) and steady-state Infrared (IR) thermography. The aft cooling insert for the vane with two-pass impingement was designed at a scale five times larger than the original and built using stereolithography (SLA) fabrication methods. The MRV technique was used to measure the three-dimensional, three-component velocity field for a test case with a Reynolds number range of 2,600 to 7,600 based on diameter of the impingement holes. Flow distribution, impingement hole performance, and cross flow effects are discussed for the experiment in which a dilute aqueous copper sulfate solution was used as the working fluid. A paired experiment with a geometrically similar design employed electrical heating of a thin stainless steel shim to model a constant heat flux boundary condition of an interior wall of the turbine vane. The modeled vane insert was then operated with air as the working fluid at two test conditions with Reynolds numbers in the range of approximately 1,200 to 7,600 based on the diameter of the impingement holes. An IR camera was used to measure the surface temperature of the shim. Using energy balances and the known heat flux, the temperature data were used to determine heat transfer characteristics of the impinging jets for the pressure and suction side surfaces, including the Nusselt number. The MRV and IR data sets provide detailed insight into the surface effects of the flow distribution and the result on the local and area-averaged heat transfer performance. A strong coupling between the velocity field and temperature data provide insight into design feature performance, and serve as a validation data set for matched computational simulations. Finally, a comparison with internal heat transfer correlations is presented using the data from Florschuetz et al. [1]. The results showed a lack of agreement with Florschuetz, leading to the development of a novel methodology for estimating the heat transfer performance of an impinging hole with crossflow. Measurement uncertainty was estimated to be ±5% for velocity and ±5% for the spatially averaged Nusselt number distributions.

Image analysis based mass transfer measurement in droplet breakage phenomenon

The effect of droplet breakage on mass transfer in copper solvent extraction was studied by measuring concentrations directly inside a droplet. Single organic phase droplet was rising through the aqueous copper sulphate solution. Organic phase consisted of hydroxyoxime type copper extractant dissolved into hydrocarbon diluent. The droplet collided with steel blade and was cut as it elongates and eventually breaks up. Droplet breakage was recorded on the video. Droplet sizes, velocities and concentrations were determined using image analysis of video frames. Results indicate that droplet breakup enhances mass transfer. Breakage and mass transfer times are short and mass transfer due to pure diffusion alone does not explain excess mass transfer. This is proposed to be due to extractant absorption on newly forming interface, which leads to increased extraction. Although measured droplet sizes are much larger than those formed in mixed tanks, the results provide insights for industrial copper extraction intensification.

In-situ investigation of wetting patterns in polymeric multibore membranes via magnetic resonance imaging

Wetting of the membrane to displace air or conditioning liquids is important to exploit the complex porosity of a filtration membrane. This study reveals the details of wetting in multibore membrane-based filtration modules. Using magnetic resonance imaging (MRI), we quantify the fluid distribution patterns during initial membrane wetting in dead-end permeation mode. The spatio-temporal evolution of aqueous copper sulfate solution wetting the membrane fibers was investigated as a function of the applied flux, packing density, and position along the membrane module length.Three initial wetting conditions were examined: delivery-state membranes, ethanol-washed and dried (air-filled) membranes, and ethanol-filled membranes. Significant changes in wetting patterns were observed due to interfacial and polymer swelling effects. This in-situ investigation reveals a slow wetting progression over six hours and more to obtain complete wetting, even at high fluxes of 200 LMH. However, an increased flux leads to faster wetting kinetics as the evolving wetting patterns are flux dependent. The packing density of the multibore fibers additionally impacts the wetting kinetics by shifting the prevalent pressure conditions. Although in dead-end mode, the wetting progression is non-uniform along the membrane module length.In addition to this parameter study, different pre-wetting agents’ effect on the displacement behavior was investigated in depth. This study helps to understand (a) complex wetting phenomena inside multibore membranes in dead-end filtration, (b) the membranes’ interaction with their surroundings due to neighboring membranes, and (c) the effect of the used fluid system for displacement on the resulting wetting patterns.

Fabrication of highly (1 1 1)-oriented Cu2O films on glass substrates by repeated chemical bath deposition

In this study, we fabricated Cu2O films on bare glass substrates by a chemical bath deposition technique, which consists of a seeding process and a subsequent film-growth process. Dense (111)-oriented Cu2O films were formed in an aqueous solution of copper (II) sulfate containing L-ascorbate and citrate ions at a low temperature of 80 °C. The film thickness and (111)-orientation degree (Lotgering factor) were both monotonically increased by simply repeating the film-growth process. As a result, a Cu2O film with a high (111)-orientation degree of 0.83 and a large thickness 1440 nm was obtained. Detailed chemical and structural characterizations suggested that as-deposited Cu2O films contained citrate ions and metallic Cu as impurities. We also found that a heat treatment at 500 °C under nitrogen flow was effective to remove these impurities.

Ammoniacal Solvoleaching of Copper from High-Grade Chrysocolla

The copper silicate ore chrysocolla forms a large potential copper resource, which has not yet been fully exploited, due to difficulties associated with its beneficiation by flotation and metallurgical processing. Direct acid leaching of chrysocolla causes silica gel formation. Therefore, in this work, the feasibility of solvometallurgical methods to leach copper from high-grade chrysocolla while avoiding issues with silica gel formation was assessed. Ammoniacal solvoleaching was performed with a solvent comprising the chelating extractant LIX 984 N or the acidic extractant Versatic acid 10 in an aliphatic diluent (ShellSol D70 or GTL Fluid G70), combined with a small volume of aqueous ammonia. In the three-phase system, aqueous ammonia dissolves copper from milled and sieved chrysocolla, while copper is simultaneously extracted to the organic phase, releasing ammonia that can be reused for further extraction. The best results were obtained with LIX 984 N as extractant: using a 50 vol% LIX 984 N solution, about 75% of copper could be extracted after 60 min of leaching at 25 °C. The stripping of copper from the pregnant leach solution was optimized. Quantitative stripping of copper was achieved with 1.89 M sulfuric acid and the final aqueous solution of copper sulfate had a concentration of 33 g L−1. Experiments in a leaching reactor (1 L) and small battery of mixer-settlers (3 stages, 35 and 143 mL effective volume in the mixer and the settler, respectively, per stage) were successfully conducted and allowed to recover copper with a purity of 99.9%. A conceptual flow sheet has been developed.Graphical

Gas discharge between two liquid electrolyte electrodes

A gas discharge between two liquid electrolyte electrodes was studied experimentally in the current range of 0.5-3.5 A. As liquid electrolytes, aqueous solutions of sodium chloride, sodium carbonate, potassium hydroxide and copper sulfate, as well as tap water, were used. The effect of composition of electrolytes on characteristics of discharge was studied at different polarities of connection to the power source.

“Tuttak Drava” an effective treatment in Ahiputana – A case study.

Tuttha also known as “Copper Sulphate” is a crystalline aqueous mineral which has been in use in Ayurveda since ancient time. “Tutthak Drava” which is one of the ayurvedic kalpa mentioned by Rasatarangini is a kalpa of Copper Sulphate. Tuttha is widely used in skin conditions as per ayurvedic texts and the kalpas varies from aqueous solution, creams, ointments, suppositories to upto oral preparation. The respective contain mainly focus on use of “Tutthak Drava” (Aqueous solution of copper sulphate i.e. 500mg CuSO4 in 50ml Water) in skin condition primarily seen in child group i.e. Ahiputana (Napkin Rash). In 21st era the use of diapers is profoundly increased and due to lack of hygiene the cases of Ahiputana has been increased. Ahiputana which is Kapha-Pitta Pradhan avastha is subsided by Kapha-Pittaghna guna of Tuttha along with Vranaghna, Lekhana, Kushtaghna and Garavishaghna guna of Tuttha . A 6 months old female child suffering from Ahiputana with complains of erythema, discharge, skin excoriation, burning sensation and tenderness at legion was treated with local application of “Tuttha Drava” by cotton pad on legion every 6hrly for 5days. The subject got significant relief within the 5days.

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

Abstract 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 pH, 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.

Studies and applications of magnetic interactions in the system “iron-copper-water”

The recovery of copper by iron in copper sulfate aqueous solutions was studies as a function of the external magnetic field and morphologies of iron containing steel samples. Essential retardation of the recovery by the magnetic field was found as well as decrease of iron sulfate solubility in water induced by the field. The retardation is explained by the active participation of inter-domain walls in the recovery and decreasing of their length in the magnetic field. When steel filings were used for the recovery instead of the volume samples the magnetic retardation was not notices. Applications of these results are developed for new methods of lithography of microschemes and restoration of electrical contact wires.

Cu NPs@NiF electrode preparation by rapid one-step electrodeposition and its sensing performance for glucose

Copper nanoparticles (Cu NPs) were uniformly deposited on a nickel foam substrate (Cu NPs@NiF electrode) rapidly by one-step electrochemical deposition in the aqueous solution of copper sulfate, which can be successfully applied to catalyze glucose oxidation, and act as a non-enzymatic glucose sensor. The specific structure and morphology of Cu NPs were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electro-oxidation of glucose on Cu NPs@NiF catalytic oxidation of process was proved by cyclic voltammetry (CV). It is found that Cu NPs show remarkable catalytic activity to glucose, involving in multistep catalytic of Cu NPs, in which the transform from Cu (II) into Cu (III) is the key to success. The performances of electrode sensitivity were investigated by CV and chronoamperometry methods in alkaline conditions. It is found that the developed sensor had excellent glucose sensing performances, including two-section broad linear detection ranges (0.002–0.650 mM and 0.65–6.00 mM), high corresponding sensitivity (2679 μA cm−2 mM−1 and 1122 μA cm−2 mM−1), fast response time (<3 s) and a low detection limit (0.5 μM, S/N = 3). In short, the Cu NPs@NiF electrode developed by low-cost, efficient and simple preparation method is expected to be used for the development of non-enzymatic glucose sensors.

Determining the Potential of a Silver/Silver Chloride Electrode at Different Temperatures

A simple and reliable way of determining the potential of a laboratory silver/silver chloride electrode (SSCE) is proposed, based on measuring the emf of a galvanic cell composed of silver/silver chloride and copper/copper sulfate (copper in a saturated aqueous solution of copper sulfate) electrodes. The standard thermodynamic characteristics of the reduction of a hexacyanoferrate(III) ion to hexacyanoferrate(II) in an aqueous solution are determined using the determined values of the SSCE potential.

Three-Dimensional Visualization of Flow Characteristics Using a Magnetic Resonance Imaging in a Lattice Cooling Channel

Flow structures in lattice cooling channels are investigated experimentally by measuring three-dimensional (3D) velocity components over entire duct. The lattice cooling structure is formed by crossing two sets of parallel inclined ribs. Heat transfer is enhanced when coolant flows through the narrow subchannels between the ribs. According to the past literature, longitudinal vortex structures are formed inside the subchannels due to interactions between crossing flows. In this study, 3D velocity field measurement is performed using magnetic resonance imaging (MRI) scanner to clarify the flow mechanism. The rib inclination angle is varied from 30 to 60 deg. Reynolds number is set at approximately 8000 based on the whole duct inlet hydraulic diameter and bulk velocity. Working fluid is 0.015 mol/L copper sulfate aqueous solution. Measured results show that coolants in the upper and lower subchannels interact not only at the both ends of the duct, but also at diamond-shaped openings formed by opposite subchannels. The exchange of momentum between the upper and lower subchannels occurs at the openings, leading to sustained longitudinal vortex in each subchannel as mentioned in the literature. When the ribs are arranged with obtuse angle, a large vortex spreads across the contact surface, while the vortex structure independently stays in each subchannel for acute rib angle. The measured velocity fields are compared with numerically-simulated ones using a Reynolds-averaged Navier-Stokes (RANS) solver. Overall flow pattern is captured, but flow interaction between the upper and lower subchannels is underestimated.