Ultrasound Capsule Endoscopy With a Mechanically Scanning Micro-ultrasound:A Porcine Study

Wireless capsule endoscopy has been used for the clinical examination of the gastrointestinal (GI) tract for two decades. However, most commercially available devices only utilise optical imaging to examine the GI wall surface. Using this sensing modality, pathology within the GI wall cannot be detected. Micro-ultrasound (μUS) using high-frequency (>20 MHz) ultrasound can provide a means of transmural or cross-sectional image of the GI tract. Depth of imaging is approximately 10 mm with a resolution of between 40–120 μm that is sufficient to differentiate between subsurface histologic layers of the various regions of the GI tract. Ultrasound capsule endoscopy (USCE) uses a capsule equipped with μUS transducers that are capable of imaging below the GI wall surface, offering thereby a complementary sensing technique to optical imaging capsule endoscopy. In this work, a USCE device integrated with a ∼30 MHz ultrasonic transducer was developed to capture a full 360° image of the lumen. The performance of the device was initially evaluated using a wire phantom, indicating an axial resolution of 69.0 μm and lateral resolution of 262.5 μm. Later, in vivo imaging performance was characterised in the oesophagus and small intestine of anaesthetized pigs. The reconstructed images demonstrate clear layer differentiation of the lumen wall. The tissue thicknesses measured from the B-scan images show good agreement with ex vivo images from the literature. The high-resolution ultrasound images in the in vivo porcine model achieved with this device is an encouraging preliminary step in the translation of these devices toward future clinical use

Improvement of the Accuracy of InSAR Image Co-Registration Based On Tie Points – A Review

Interferometric Synthetic Aperture Radar (InSAR) is a new measurement technology, making use of the phase information contained in the Synthetic Aperture Radar (SAR) images. InSAR has been recognized as a potential tool for the generation of digital elevation models (DEMs) and the measurement of ground surface deformations. However, many critical factors affect the quality of InSAR data and limit its applications. One of the factors is InSAR data processing, which consists of image co-registration, interferogram generation, phase unwrapping and geocoding. The co-registration of InSAR images is the first step and dramatically influences the accuracy of InSAR products. In this paper, the principle and processing procedures of InSAR techniques are reviewed. One of important factors, tie points, to be considered in the improvement of the accuracy of InSAR image co-registration are emphatically reviewed, such as interval of tie points, extraction of feature points, window size for tie point matching and the measurement for the quality of an interferogram

Effect of Different Water-retention Agents and Marination Methods on the Water-holding Capacity of Microwave Spicy Chicken Wings

The effects of water retaining agents and marination methods on the water-holding capacity (WHC) of microwave spicy chicken wings were explored in this study, and it provided a full theoretical framework for the study of WHC in microwave-type seasoned meat products. The optimal formulation of water retention agent was investigated in this research with the addition of complex phosphate, k-carrageenan, and maltodextrin as influencing factors and pH, myogenic fibrin hydration characteristics, shear force, centrifugal loss rate and microwave loss rate as indexes. After optimization, the optimal water retention agent formulation was 0.33% of compound phosphate, 0.21% of k-carrageenan, and 0.24% of maltodextrin, with pH, solubility, hydrophobicity, shear force, centrifugal loss rate and microwave loss rate of chicken wings being 6.34, 57.29%, 25.76 μg, 25.76 N, 19.06%, and 24.57%, respectively, and the normalized composite scores reached a maximum value of 0.9846. A static marination group was used as a blank control, and indicators such as marinade absorption rate, yield, sensory scores and moisture distribution were used to study the effect of marination methods on the water retention of chicken wings. When the marination time was increased to 2 h, the absorption rate of marinade, yield, sensory scores, P21, and P in the tumbling marination group increased by 56.44%, 7.56%, 10.73%, 10.18%, and 14.95%, respectively, when compared to the static marination group, and the relaxation time T21 was 25.708 and 21.465 ms in the static and tumbling marination groups, respectively, indicating that the water retention of the tumbled-cured chicken wings was greatly improved. The microwave spicy chicken wings produced under these conditions were moderately firm, elastic, and tender

Catalytic Degradation of Organic Contaminants by Microwave-Assisted Persulfate Activation System: Performance and Mechanism

In this study, a nickel ferrite (NiFe2O4) system was constructed to purify a phenol solution in water. During the process, the influences of several critical operating parameters including the NiFe2O4 amount, PS dosage, MW power, initial pH value, and different natural water anions were systematically studied. The results indicated that the constructed system performed excellently regarding the removal efficiency (97.74%) of phenol within 30 min. Meanwhile, the influence of co-existing anions such as Cl−, NO3−, H2PO4−, and HCO3− was also studied, which displayed an inhibiting action on phenol degradation, while HA facilitated it. To explore the reaction mechanism of this system, major free radical quenching experiments were conducted, and it was confirmed that both SO4•− and HO• were primary radicals. Moreover, stability experiments confirmed the apt stability of the NiFe2O4 system. Besides, the mineralization and toxicity analysis performed during phenol degradation also confirmed the superiority of the as-constructed system. Furthermore, the possible degradation mechanism of phenol was proposed. Hence, this system could be applied in advanced wastewater treatment

Selective Water Plugging Technology for Horizontal Well with Screen Completion

The SD107 gel system developed has good oil–water phase selective gelation and oil–water phase selective blocking properties. The static gel-forming experiment results showed that the gel water shutoff system formulated with oilfield reinjection water (oil content Q) of the oil well to be blocked, the maximum production pressure difference (∆P) was predicted, and on the basis of economic output, the resistance of the oil section, the resistance of the high water cut section, and the resistance of the water outlet section after plugging was used to calculate the plugging depth (re1, the limit water plugging radius), which offers a basis for the design of water plugging process parameters for horizontal wells. The field water plugging test results showed that after using this water plugging technology, the daily oil production increased from about 4 t/d to 20 t/d, the daily oil increase was 16 t/d, and the water cut decreased from 75% to about 25%. The water-blocking construction was a success

Experimental study on the phenomenon of gas–liquid flow in divertor and diffuser under blowout condition

In the Experimental Advanced Superconducting Tokamak (EAST), the water in the cooling channel of the divertor needs to be pushed out by the blowout system to avoid water leakage, otherwise it will further endanger the safe operation. However, diffusers often used to change the pipe size have an adverse effect on the water discharge in divertors. Therefore, research on the blowout process in the divertor and diffuser is essential to improving the dryness of the blowout system. In this paper, the mutual restriction between divertor and diffuser is proposed by the experiment research, such restriction is an important factor in reducing the dryness of the divertor. According to the experimental results, the larger the resistance loss is in the divertor, the smaller the effective pressure difference will be in the diffuser. Meanwhile, liquid phase water flows rotationally in the diffuser under a small pressure difference, thus reducing the dryness of the divertor. Moreover, the diffuser increases the pressure difference required for complete blowout in the divertor. These results will provide a reference for the design and optimization of the EAST blowout system in the future

Effect of the Internal Humidity of Concrete on Frost Resistance and Air Void Structure under Different Low Temperature Conditions

From the perspective of combining macroscopic and microscopic properties, this paper simulates the freeze–thaw cycle process at different freezing low temperatures based on the climate simulation equipment and by setting the curing conditions with different temperatures and relative humidity to produce different moisture conditions in concrete. The frost resistance properties and microscopic air void performance of concrete with different internal water content under different freezing low temperatures in freeze–thaw cycles were systematically studied. The results show that the higher the internal water content of concrete, the more obvious the mass loss rate and dynamic elastic modulus loss of concrete in the freeze–thaw process, and the more serious the deterioration of the air void parameter performance of the air-entraining agent introduced into concrete, which is manifested as the average bubble diameter and bubble spacing factor become larger and the bubble specific surface area decreases. In addition, in the case of the same internal moisture content of concrete, the freezing temperature used in the freeze–thaw cycle also has an important impact on the frost resistance of concrete and air void parameters; the lower the freezing temperature used, the more significant the decline in the frost resistance of concrete, the more obvious the deterioration of air void parameters