Concentration Of Agent Research Articles

Dissolution Mechanism of Physical Blowing Agent into the Polymer in Low-pressure Physical Foam Injection Molding Process (Part 1) Effect of Molding Conditions on Physical Blowing Agent Concentration

Dissolution Mechanism of Physical Blowing Agent into the Polymer in Low-pressure Physical Foam Injection Molding Process (Part 1) Effect of Molding Conditions on Physical Blowing Agent Concentration

Study on the scale inhibition performance of organic chelating agent aided by surfactants on CaCO3 at high salinity condition

Abstract The salt blockage layer formed in the wellbore during the development of high salinity oil and gas fields has a serious impact on the safety of oil and gas production of the oil and gas fields. CaCO3 is the main component of scale in high salinity oil and gas fields. Herein, focusing on CaCO3 as an example, the precipitation and scaling process as well as the change of crystalline form of CaCO3 under different temperature and salinity conditions were studied. The effects of two addition methods of organic chelating agent on the solubilization and dislodgement of CaCO3 under high salinity conditions were also explored. The optimal concentration of organic chelating agent is determined to be 1 % and 5 % for solubilization and dislodgement, respectively. It was found that the solubilization is achieved by inhibiting the stable and difficult to treat calcite crystal phase to generate more irregular and more dispersed aragonite CaCO3. Organic chelating agent contains a large number of carboxyl groups in its molecules, which can be adsorbed onto the surface of CaCO3 crystals through electrostatic adsorption. By chelating Ca2+ in stable and difficult to treat calcite CaCO3, the further ordered growth of the crystals is prevented, causing lattice distortion or large crystal rupture, thereby achieving dislodgement. This study will provide theoretical and technical support for the solubilization and dislodgement of salt blockage layer in wellbore at high salinity conditions.

A Novel In-Line Measurement and Analysis Method of Bubble Growth-Dependent Strain and Deformation Rates during Foaming.

Bubble growth processes are highly influenced by the elongational viscosity of the blowing agent-loaded polymer melt. Therefore, the elongational viscosity is an important parameter for the development of new polymers for foaming applications, as well as for the prediction of bubble growth processes. Thus, knowledge of the initial expansion and deformation behavior in dependency on the polymer, the blowing agent concentration, and the process conditions is necessary. This study presents a novel method for the in-line observation and analysis of the initial expansion and deformation behavior within the bead foam extrusion process. For this purpose, nitrogen as the blowing agent was injected into the polymer melt (PS and PLA) during the extrusion process. The in-line observation system consists of a borescope equipped with a camera, which was integrated into the water box of an underwater pelletizer. The camera is controlled by a developed trigger by means of angular step signal analysis of a rotary encoder on the cutter shaft of the underwater pelletizer. Thus, images can be taken at any time during the foaming process depending on the cutter position to the die outlet. It is shown that the developed method provides reliable results and that the differences of the initial expansion and deformation behavior during bubble growth can be analyzed in-line in dependency on real foaming process conditions and the type of polymer used.

Research on hot water chemical flooding technology in Bohai heavy oil field

Introduction: The hot water chemical flooding technology effectively improves the fluidity ratio and enhances the horizontal and vertical oil displacement efficiency of the reservoir through the synergistic effect of thermal energy and chemicals, which can further enhance the recovery rate on the basis of throughput thermal recovery.Methods: Based on the geological reservoir parameters of Bohai B oilfield, an oil recovery system evaluation experiment and scheme design study were carried out. Injection parameters such as hot water temperature, chemical agent concentration, and chemical agent dosage that affect the oil recovery effect of hot water chemical flooding were optimized and designed. The development characteristics and effects of two thermal recovery technologies, namely multi thermal fluid throughput and hot water chemical flooding, were compared and analyzed.Results: The results show that with the increase of temperature, the effect of chemical agents on improving the water-oil mobility ratio and reducing the viscosity of crude oil is weakened, and the thermal energy plays a leading role in enhancing oil recovery, but when the temperature is higher than 115°C, the improvement of oil recovery is slowed down, and the comprehensive economic indicators decline rapidly. As the concentration of chemical agent increases, the enhanced oil recovery increases monotonously. When the concentration is 1500 mg/L, the comprehensive economic indicators reach the peak and then decline, indicating that the efficiency of chemical agent decreases. The total amount of chemical agent shall be controlled within 0.25 ~ 0.30 PV. The case calculation shows that hot water chemical flooding can expand the effective radius from 80 m to 400 m, more effectively use the reserves between injection and production wells, increase the oil recovery by 4.8 percentage points, and increase the oil yield by 31.7 m3/t per ton of agent.Discussion: It is suggested that Bohai B Oilfield can adopt hot water chemical flooding after the multiple thermal fluid huff and puff to continuously guarantee the oilfield production.

Improving tumor treatment through intratumoral injection of drug-loaded magnetic nanoparticles and low-intensity ultrasound

The intratumoral injection of therapeutic agents responsive to external stimuli has gained considerable interest in treating accessible tumors due to its biocompatibility and capacity to reduce side effects. For the first time, a novel approach is explored to investigate the feasibility of utilizing low-intensity ultrasound in combination with intratumoral injection of drug-loaded magnetic nanoparticles (MNPs) to thermal necrosis and chemotherapy with the objective of maximizing tumor damage while avoiding harm to surrounding healthy tissue. In this study, a mathematical framework is proposed based on a multi-compartment model to evaluate the effects of ultrasound transducer’s specifications, MNPs size and distribution, and drug release in response to the tumor microenvironment characteristics. The results indicate that while a higher injection rate may increase interstitial fluid pressure, it also simultaneously enhances the concentration of the therapeutic agent. Moreover, by increasing the power and frequency of the transducer, the acoustic pressure and intensity can be enhanced. This, in turn, increases the impact on accumulated MNPs, resulting in a rise in temperature and localized heat generation. Results have demonstrated that smaller MNPs have a lower capacity to generate heat compared to larger MNPs, primarily due to the impact of sound waves on them. It is worth noting that smaller MNPs have been observed to have enhanced diffusion, allowing them to effectively spread within the tumor. However, their smaller size also leads to rapid elimination from the extracellular space into the bloodstream. To summarize, this study demonstrated that the local injection of MNPs carrying drugs not only enables localized chemotherapy but also enhances the effectiveness of low-intensity ultrasound in inducing tissue thermal necrosis. The findings of this study can serve as a valuable and reliable resource for future research in this field and contribute to the development of personalized medicine.

Predicting muscarinic receptor occupancy in human bladder mucosa from urinary concentrations of antimuscarinic agents for overactive bladder

To assess the pharmacologically relevant and selective muscarinic receptor occupancy in the bladder mucosa, we considered not only plasma drug concentrations but also urinary drug concentrations. The purpose of this study was to predict muscarinic receptor occupancy in the human bladder mucosa based on urinary concentrations in response to clinical dosages of antimuscarinic agents used to treat overactive bladder. The calculated mean plasma or serum unbound steady state concentrations were 0.06–11 nM in clinical dosages of five antimuscarinic agents. Urinary concentrations calculated from the mean plasma or serum and renal clearance ranged between 19 nM and 2 μM, which were >10-fold higher than the Ki values for bladder muscarinic receptors excluding propiverine. Bladder mucosal muscarinic receptor occupancy estimated from the urinary concentrations and the Ki values was >90 % at a steady state in clinical dosages of five antimuscarinic agents. The bladder muscarinic receptor occupancy was higher than that in the parotid gland calculated based on the mean plasma or serum unbound concentrations and Ki values for muscarinic receptors in the parotid gland. These results suggest that sufficient and selective muscarinic receptor occupancy by antimuscarinic agents, to exert pharmacological effects, in the bladder mucosa can be predicted using urinary concentrations.

Determination of the Optimal Concentration of Natural Antimicrobial Agents in Marinade Sauce for Meal Kits

This study aimed to determine the antimicrobial effectiveness of natural antimicrobial agents (NAAs) (yuzu juice, wasabi extract, and rosemary extract) against three target microorganisms (TMs) (Escherichia coli, Staphylococcus aureus, and Salmonella Typhimurium) and to determine the optimal concentration of these agents using response surface methodology (RSM) to ensure the safety of meal kits manufactured using marinade sauce. The three NAAs added to marinade sauce effectively inactivated TMs (P<0.05), in particular, yuzu juice had the greatest antimicrobial effect against TMs, followed by wasabi and rosemary extracts. To determine the optimal concentration of NAAs using RSM, 17 concentrations were tested with three TMs as dependent variables and three NAAs as independent variables. The results showed that E. coli was not present under any of the conditions tested, whereas S. aureus and S. Typhimurium exhibited different characteristics depending on the conditions. Through response surface analysis of the TMs except for E. coli, which was not detected, it was determined that S. aureus had a coefficient of determination (R2) of 0.928 and a lack of fit of 0.074, and the linear regression of [yuzu juice] (X1) and quadratic regression of [yuzu juice]2 (X12) were both significant (P<0.05). S. Typhimurium had an R2 of 0.8955 and a lack of fit of 0.051, and only the quadratic regression of [yuzu juice]2 (X12) was significant (P<0.05). Based on RSM and ridge analysis, the optimal mixed conditions were determined to be 3.92% (v/w) yuzu juice, 23.41% (v/w) wasabi extract, and 3.93% (v/w) rosemary extract. After investigating the antimicrobial effect under the optimal conditions, E. coli and S. Typhimurium were absent, and S. aureus was reduced to 2.50 ± 0.09 log colony-forming units/g after 24 h. The results indicated that mixed treatment with the three NAAs had a more significant antimicrobial effect due to their synergistic properties compared to when used in isolation.

The Effect of Foaming Agent and Whipping Time on Albedo Characteristics of Watermelon Flour

The fruit's rind is one of the natural waste products that can support nutrients like carbohydrates, proteins, and lipids. Reused rind contributes significantly to the effective handling of this fruit's byproduct. Processing watermelon rind into powder by lowering water content and activity is an alternative to extending its shelf life. The flour form is easier and more suitable for application in multiple processing food products such as snacks, beverages, bread, and pasta. The focus of this study was to verify the optimal state for foam mat drying using concentrations of foaming agent in the form of egg albumin (10, 15, 20), foam stabilizer in the form of CMC with concentrations of 1 %, and whipping time (5, 7, and 9 minutes) on for bulk density, WSI, hygroscopicity, L* value, a* value, b* value of total phenol and antioxidants activity, and the maximum antioxidant content of watermelon albedo flour using Completely Randomized design with 2 factorial resulting in nine treatments with three replications. Based on the outcome, the bulk density of the resulting watermelon albedo flour ranges from 0.25-0.50 gr/cm-3 and 0.11-0.26%. of WSI; 22.63-28.18g/100g-1 of hygroscopicity; 1.92-4.67% of total phenol; 47.48-66.59% of L*value; 3.74-6.11% of a*value; 5.47-16.08% of b*values and 6.80- 25.26% RSa of antioxidants activity. The best treatment for antioxidant activity was 25.26% RSA using 10% of the foaming agent and whipping time in 9 minutes. These findings have implications for the food industry because they suggest that treatments can influence the properties of watermelon albedo flour.

Radiation source personalization for nanoparticle-enhanced radiotherapy using dynamic contrast-enhanced MRI in the treatment planning process

Nanoparticle-enhanced radiotherapy offers the potential to selectively increase the radiation dose imparted to the tumor while at the same time sparing the healthy structures around it. Among the recommendations of an interdisciplinary group for the clinical translation of this treatment modality, is the developing of methods to quantify the effects that the nanoparticle concentration has on the radiation dosimetry and incorporate these effects into the treatment planning process. In this work, using Monte Carlo simulations and dynamic contrast-enhanced MRI images, treatment plans for nanoparticle-enhanced radiotherapy are calculated in order to evaluate the effects that realistic distributions of the nanoparticles have on the resultant plans and to devise treatment strategies to account for these effects, including the selection of the proper x-ray source configuration in terms of energy and collimation. Dynamic contrast-enhanced MRI studies were obtained for two treatment sites, namely brain and breast. A model to convert the MRI signal to contrast agent concentration was applied to each set of images. Two treatment modalities, 3D conformal radiotherapy and Stereotactic Body Radiation Therapy, were evaluated at three different x-ray spectra, namely 6 MV from a linear accelerator, 110 kVp and 220 kVp from a tungsten target. For the breast patient, as the nanoparticle distribution varies markedly with time, the treatment plans were obtained at two different times after administration. It was determined that maximum doses to the healthy structures around the tumor are mostly determined by the minimum nanoparticle concentration in the tumor. The presence of highly hypoxic or necrotic tissue, which fails to accumulate the nanoparticles, or leakage of the contrast agent into the surrounding healthy tissue, make irradiation with conventional conformal radiotherapy unfeasible for kilovoltage beam energies, as the uniform beam apertures lack the ability to compensate for the non-uniform distribution of the nanoparticles. Therefore, proper quantification of the nanoparticle distribution not only in the target volume but also in the surrounding tissues and structures is crucial for the proper planning of nanoparticle-enhanced radiotherapy and a treatment delivery with a high-degree of freedom, such as small-field stereotactic body radiotherapy, should be the method of choice for this treatment modality.

Strategy For Controlling Bacterial Leaf Blight (Xanthomonas sp.) on Eucalyptus Pellita Plants by Administering P. aeruginosa RE081

The demand for Eucalyptus Pellita seeds as a high-throughput inoculum (HTI) crop commodity in the field is extremely high. However, Xanthomonas sp., a bacteria that causes bacterial leaf blight, poses a significant challenge in ensuring a steady supply of healthy seedlings in nurseries. Researchers have explored using the rhizobacteria P. aeruginosa RE081 as an environmentally friendly biocontrol agent to address this issue. This study aims to determine the optimal concentration of P. aeruginosa RE081 that can effectively reduce the incidence and severity of bacterial leaf blight caused by Xanthomonas sp. The research was conducted using a completely randomized design, with different concentrations of P. aeruginosa RE081 (105, 106, 107, 108 CFU/mL) being tested. The findings indicate that the biological agent's concentration significantly impacts plant disease occurrence and severity. In vivo testing revealed that P. aeruginosa RE081 reduced disease severity by only 2.13% at a 108 CFU/mL concentration. Interestingly, concentrations lower than 108 CFU/mL increased disease severity compared to the control group.

Effective Utilization of Sulfur Wastewater by Photocatalytic System Using B/CuO/ZnO

B-doped zinc oxide/copper oxide composites prepared using a simple method showed high photocatalytic hydrogen production activity in the presence of aqueous sulfide solutions. Co-modification of the CuO composite with B-doping caused an increase in the charge separation efficiency and light absorption capacity. The sacrificial effect was thermodynamically enhanced by manipulating the composition of the sulfide solution. A maximum hydrogen production activity of 224 μmol g−1 h−1 was achieved under 450 nm light irradiation in a photocatalytic system with optimized B doping, a CuO composite, and a sulfide sacrificial agent concentration.

On recycling earth pressure balance shield muck with residual foaming agent: defoaming and antifoaming investigations.

Earth pressure balance (EPB) shield is increasingly employed in metro tunnel construction, and causes a series of environmental, safety, and resource waste problems due to the disposal of a considerable amount of muck. In situ recycling of EPB shield muck is an effective solution, whereas the foam is generated by residual foaming agents used as the muck conditioning material during tunnelling, which often adsorbs clay particles and overflows the flocculation tank. To achieve defoaming and antifoaming during the reuse of muck, this study prepared novel eco-friendly silicone oil-polyether defoamers by condensation, compounding, and shear emulsification. Defoaming and antifoaming performances of different defoamers were tested using a modified Ross-Miles method and a scale model of field flocculation systems. The results indicated that a high efficiency in defoam and antifoam was characterized by chemical grafting of nano-SiO2 from silicone oils, uniform distribution and large size of grains, low viscosity, and surface tension. The defoamer dosage of 0.002-0.004 wt% near critical micelle concentration (CMC) for each defoamer is reasonable. Overall, the prepared hydroxyl silicone oil-glycerol polyoxypropylene ether (H-G) defoamer compared with other silicone oil-polyether defoamers and commercial defoamers presents the highest defoaming and antifoaming efficiency. Considering the effects of EPB shield muck, the H-G defoamer is least affected by the compound materials and increasing concentration of the commercial foaming agent. Nevertheless, the stability of the H-G emulsion system is weaker than that of the dimethyl silicone oil-glycerol polyoxypropylene ether (D-G) emulsion system after 1 month of sealed storage.

In-situ swelling of pH-responsive microgel particles during photopolymerization to mitigate shrinkage stress of UV-cured materials

This paper utilizes a soap-free emulsion polymerization process to prepare microgel particles that can swell in response to in-situ generated acid in photocurable resin. By controlling the type and concentration of end-capping agents and the content of cross-linking agents, pH-responsive microgel particles with significantly increased particle size in acidic environments are synthesized. The strong protonic acid generated by the photoacid upon exposure to ultraviolet light can reduce the pH of the UV-curable resin, leading to an enlargement of the particle size. This can compensate for the volume shrinkage of the resin, ultimately reducing shrinkage stress. The research findings indicate that the addition of 5 wt% of pH-responsive particless and 2 wt% of photoacid to the UV-curable resin results in a reduction of approximately 40% in shrinkage stress and shrinkage rate.

Poly(ethylene glycol) Methyl Ether Acrylate-Grafted Chitosan-Based Micro- and Nanoparticles as a Drug Delivery System for Antibiotics.

Nanotechnology is the science of creating materials at the nanoscale by using various devices, structures, and systems that are often inspired by nature. Micro- and nanoparticles (MPs, NPs) are examples of such materials that have unique properties and can be used as carriers for delivering drugs for different biomedical applications. Chitosan (CS) is a natural polysaccharide that has been widely studied, but it has a problem with low water solubility at neutral or basic pH, which limits its processability. The goal of this work was to use a chemically modified CS with poly(ethylene glycol) methyl ether acrylate (PEGA) to prepare CS micronic and submicronic particles (MPs/NPs) that can deliver different types of antibiotics, respectively, levofloxacin (LEV) and Ciprofloxacin (CIP). The particle preparation procedure employed a double crosslinking method, ionic followed by a covalent, in a water/oil emulsion. The studied process parameters were the precursor concentration, stirring speeds, and amount of ionic crosslinking agent. MPs/NPs were characterized by FT-IR, SEM, light scattering granulometry, and Zeta potential. MPs/NPs were also tested for their water uptake capacity in acidic and neutral pH conditions, and the results showed that they had a pH-dependent behavior. The MPs/NPs were then used to encapsulate two separate drugs, LEV and CIP, and they showed excellent drug loading and release capacity. The MPs/NPs were also found to be safe for cells and blood, which demonstrated their potential as suitable drug delivery systems for biomedical applications.

Effect of N-acetyl cysteine, rifampicin, and ozone on biofilm formation in pan-resistant Klebsiella pneumoniae: an experimental study.

To the best of our knowledge, this is the first study to evaluate the effectiveness of specific concentrations of antibiofilm agents, such as N-acetyl cysteine (NAC), rifampicin, and ozone, for the treatment of pan-resistant Klebsiella pneumoniae (PRKp). We evaluated the effectiveness of antibiofilm agents, such as NAC, rifampicin, and ozone, on biofilm formation in PRKp at 2, 6, 24, and 72 h. This single-center experimental study was conducted on June 15, 2017, and July 15, 2018, at Istanbul Faculty of Medicine, Istanbul University, Turkey. Biofilm formation and the efficacy of these agents on the biofilm layer were demonstrated using colony counting and laser-screened confocal microscopy. NAC at a final concentration of 2 μg/mL was administered to bacteria that formed biofilms (24 h), and no significant decrease was detected in the bacterial counts of all isolates (all P > 0.05). Rifampicin with a final concentration of 0.1 μg/mL was administered to bacteria that formed biofilm (24 h), and no significant decrease was detected in bacterial count (all P > 0.05). Notably, ozonated water of even 4.78 mg/L concentration for 72 h decreased the bacterial count by ≥ 2 log10. Different approaches are needed for treating PRKp isolates. We demonstrate that PRKp isolates can be successfully treated with higher concentrations of ozone.

Toxicokinetics of a developmental toxicity test in zebrafish embryos and larvae: Relationship with drug exposure in humans and other mammals

To study the effects of drugs on embryo/fetal development (EFD), developmental and reproductive toxicity studies in zebrafish (Danio rerio) embryos is expected to be an accepted alternative method to animal studies using mammals. However, there is a lack of clarity in the relationship between the concentration of developmental toxicity agents in whole embryos or larvae (Ce) and that in aqueous solution (Cw), and also between the amount of drug exposure required to cause developmental toxicity in zebrafish embryos or larvae and that required in mammals. Here, we measured Ce for developmental toxicity agents every 24 h starting at 24 h post fertilization (hpf). We found a high correlation (R2: 0.87–0.96) between log [Ce/Cw] and the n-octanol–water distribution coefficient at pH 7 (logD) of each drug at all time points up to 120 hpf. We used this relationship to estimate the Ce values of the 21 positive-control reference drugs listed in ICH guidelines on reproductive and developmental toxicity studies (ICH S5). We then calculated the area under the Ce–time curve in zebrafish (zAUC) for each drug from the regression equation between log [Ce/Cw] and logD and compared it with the AUC at the no-observed-adverse-effect level in rats and rabbits and at the effective dose in humans described in ICH S5. The log of the calculated zAUC for the 14 drugs identified as positive in the zebrafish developmental toxicity test was relatively highly positively correlated with the log [AUC] for rats, rabbits, and humans. These findings provide important and positive information on the applicability of the zebrafish embryo developmental toxicity test as an alternative method of EFD testing. (267 words)

Rate retardation trends in RAFT – an emerging monomer classification tool?

The RAFT rate retardation effect is used to classify monomers according to their reactivity. The stability of the radical correlates inversely with the extent of retardation allowing a framework for classifying monomer reactivity to be established.

Discrete and analog evaluation of the capillary-pore space of foam concrete in eco-friendly production

Relevance. The aim of the study was to identify and study the analytical dependencies of technological parameters and aspects of the preparation of foam concrete depending on the concentration of foaming agents at various points in the formation of the capillary-porous structure. It is important to evaluate the possibility of using them to obtain environmentally friendly performance properties of “poro-concrete”, as it is often used in the construction of agricultural facilities. In the course of optical studies, the carbon footprint in the components of the composite materials under study was tracked. The distribution of pore sizes across auto-modal clusters is determined. Dispersion analysis of surface sections of foam concrete was carried out. Based on the discrete analysis of the concrete structure, analog analytical dependences were obtained linking the studied properties of foam concrete with the parameters of density, eco-friendly, porosity, and other parameters. In the construction of agricultural facilities these properties are particularly important.

Comparative study on mechanisms of gases release from Ca-alginate beads

Calcium alginate (Ca-alginate) beads have attracted considerable attention as carriers for the controlled release of volatile compounds due to their biocompatibility and tunable properties. This study aimed to compare the release of ethylene and carbon dioxide gas from Ca-alginate beads. Ca-alginate beads were prepared from a sodium alginate solution containing ethephon and calcium carbonate as the gas-forming agent. The resulting solution was then extruded into a calcium chloride solution. The gas release behavior was studied by monitoring the concentration of released gases over time using gas detectors. Extrusion tip diameter, alginate concentration and gas-releasing agent concentration were systematically varied to assess their effect on the gas release rate. The results indicated distinct release patterns for ethylene and carbon dioxide gas. Ethylene gas exhibited a relatively slower and sustained release, while carbon dioxide gas exhibited a more rapid release. Moreover, the bead size influenced the gas release, with larger beads displaying faster release rates for ethylene and carbon dioxide gas. The concentration of alginate also played a role in modulating the release kinetics, with higher alginate concentration resulting in slower gas release. The findings have implications for designing and optimizing Ca-alginate-based systems for agricultural applications, including plant hormone delivery and modified atmosphere packaging.

Experimental study on the effects of different exposure conditions and contrast agent concentrations on spectral computed tomography virtual non-contrast images.

The early diagnosis of thrombosis and fat embolism is important for subsequent treatment regimens. Spectral computed tomography (CT) virtual non-contrast (VNC) scanning can not only accurately diagnose thrombosis and medium fat embolism but can also reduce the radiation dose and scanning time. However, there is a relative paucity of studies on what contrast concentration and exposure conditions are best for the quality of VNC images. To address this issue, this study aimed to investigate the effects of different exposure conditions and contrast concentrations on the quality of VNC images of low-density substances in spectral CT. Four solution groups [i.e., groups A (15 mgI/mL), B (10 mgI/mL), C (5 mgI/mL), and D (the control group)] were matched with normal saline and contrast agent groups. Four groups of solution, duck blood clots, and fat were injected into four sections of the pig large intestine, respectively. CT scans with different exposure amounts were performed under the condition of 120 KV. Comparing the true non-contrast (TNC) image based on solution D group with the VNC images of the other three solution groups. The differences in the CT values, standard deviation (SD) values, and contrast noise ratio (CNR) values of the duck blood and fat under different iodine concentrations and exposures were compared. The image quality was evaluated using a three-point method and the Kappa consistency test was performed. The consistency of the tissue CT values in the TNC and VNC images was analyzed by drawing Bland-Altman scatter plots. The CT values of the duck blood in the VNC20mAs and VNCC groups were lower than those in the TNC groups (P<0.05). Under different exposures and contrast agent concentrations, the CT value of the fat in the VNC group was higher than that in the TNC group (P<0.05). The SD values of the duck blood and fat in three groups (i.e., groups A, B, and C) were lower than those in the TNC group (P<0.05). The CNR value of the duck blood in the VNC20mAs group was lower than that in the TNC group (Z=-2.10, P=0.04), and the CNR values of the duck blood and fat in the VNC group were higher than those in the TNC groups in the remaining different exposure and concentration groups (P<0.05). The CT values of the lesions in the two groups were consistent, and there were no statistically significant differences between the subjective scores of the TNC and VNC images (z=-1.34, P=0.18); the subjective evaluations of the two physicians had good consistency (K=0.80). Under the conditions of higher contrast agent concentrations and proper exposure conditions, the VNC images were better able to restore the CT values of the blood clots, reduce the SD values of the blood clots and fat. In addition, and improve the CNR values of the blood clots and fat. In addition, the quality of the two images was similar.