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Casing shear deformation has become a prominent problem in the process of completion in shale gas wells. It was believed that the slide of strike‐slip fault induced by multistage fracturing was the main reason. This paper presented a new numerical investigation for evaluating the casing inner diameter after strike‐slip fault sliding based on the microseismic data. A 3D finite element model, considering the mechanical anisotropy of shale and heat‐fluid‐solid coupling effect during multistage fracturing, was developed to calculate the variation of casing inner diameter after fault sliding under different engineering and geological conditions. The calculation result was verified by comparison with the measurement result of the multi‐finger caliper survey. Sensitivity analysis was carried out and the results showed that decreasing the sliding distance, maintaining high pressure, increasing the casing thickness, and increasing the elasticity modulus and decreasing the Poisson ratio of cement sheath were beneficial to protect the casing integrity. Finally, the engineering verification demonstrated that the numerical method has an accuracy up to 85.9%. Numerical model in this study was expected to provide a better understanding of casing shear deformation and an evaluation method of casing inner diameter after fault sliding during multistage fracturing in shale gas wells.

Detonation performances of methane/hydrogen/oxygen (CH4/H2/O2) mixtures were investigated experimentally in a 3000 mm long tube with an inner diameter of 30 mm at different initial pressures p 0 (ranging from 10 kPa to 50.5 kPa). Mixtures with different proportions of H2 in the total fuel α (0%, 14.29% and 25%) and different equivalence ratios Φ (0.8, 1.0 and 1.2) were tested. Signals of flame front and pressure were obtained by ion probes and high frequency pressure transducers, respectively. Results showed that with the increase of p 0 , α and Φ , the average velocity of steady detonation V a v e increased. For mixtures with the given α , when Φ increased by 0.2, V a v e increased by 100 m/s. In the present study, velocity deficits were found to be within 5%, and when p 0 was higher than 20 kPa, the velocity deficits were within 2%. The average peak pressure of steady detonation p a v e was close to the von Neumann pressure p v N . Both the increase of p 0 and Φ led to the increase of the p a v e . But the addition of H2 led to the decrease of p a v e , and p a v e decreased with the increased of α .

In this study the electrostatic charging behaviour of single particles of different sizes and materials were investigated during pneumatic conveying. The particles used included 3.18 and 0.79 mm PTFE as well as 3.18 mm Nylon particles. Particles were pneumatically conveyed in stainless steel (316 Grade) tubes with 4.57 mm inner diameter. Effects of conveying tube length, conveying gas velocity and pathway of particles (i.e. addition of 90° elbows and smooth bends) on particles charge-to-mass ratio were studied. Results showed that the smaller PTFE particles reached the saturation charge in the longest straight tube at all conveying gas velocities tested. Whereas the other two larger particles reached saturation charge only in the longest straight tube and at the lowest gas velocity. For large particles moving in straight tubes, in general, the lowest gas velocity resulted in a higher charge-to-mass ratio. The particles pathway had a large impact on their charging behaviour at high gas velocities, whereas at the lowest gas velocity, the total tube length was more influential on particles charging. Finally, the charge of the particles determined by measuring the current from the conveying line was found to be in good agreement with that measured directly by a Faraday cage.

Pulmonary hypertension is characterized by elevation of pulmonary artery (PA) pressure (p) and structural remodeling of the PA wall, leading to reduction in arterial compliance (c). As a step towards improving diagnosis of pulmonary disease, we use the PA branch geometry (main pulmonary artery (MPA) branching into left (LPA) and right (RPA) pulmonary arteries) obtained from MRI in conjunction with an inverse algorithm to obtain the pre-stress level in the artery walls. Next, a coupled blood–wall interaction (BWI) calculation provides hemodynamic information as well as compliance of the PA walls. We show that the computed load-free geometry from the inverse algorithm exhibits a 27.8% lower inner diameter (d) and 18.5% lower outer d compared to the in vivo geometry from MRI. Further, the mean p computed from the BWI computation in the main PA ( p M P A − n ) is within 4% of the mean p M P A − e (n-numerical; e-experimental). Also, the mean Q computed in the left PA ( Q L P A − n ) is within 10% of the mean Q L P A − e . Finally, the compliance c M P A − n is computed to be 27% lower than c M P A − e , while the c L P A − n is computed to be 20.4% lower than c L P A − e . Importantly, the PA shows significant intra-vascular variation in compliance, with the MPA showing higher overall compliance compared to the LPA (3.5–4 times).

The flow characteristics of CO2 hydrate in the presence of Tween 80 in a scaled-up test facility were investigated in order to further elucidate the potential of CO2 hydrate slurry transportation in carbon capture and storage technology. Two formation processes were used to generate sufficient hydrate slurry for flow in a circulation loop of a 108 mm inner diameter pipe. The effects of Tween 80 concentrations on the four hydrate slurry parameters of pressure, temperature, density, and flow rate were studied and discussed. The results of the CO2 hydrate slurry transportation experiments indicated that 0.7 wt.% of Tween 80 showed the optimal results for slurry stability, slurry temperature, and slurry density, but had no significant effect on slurry temperature during flowing in the loop. In all experiments, hydrate circulation was performed for an average duration of 80 min under stable conditions. The results suggest the possibility of transporting hydrate slurry over long distances under stable conditions with the addition of chemical additives.

Thermal barrier coatings (TBCs) with high thermal strain tolerance and erosion resistance are commonly applied onto the inner and outer diameters of hot sections of gas-turbine engine components. In this work, strain-tolerant, segmented TBCs were developed using the SinplexPro-cascaded torch. Design of experiments were carried out to study the effect of process variables such as plasma power, powder feeding rate, spraying distance and surface speed on the coating microstructure and properties. Optimized process parameters for the segmented coating microstructures at shorter spray distance ( 114mm) are achieved, which are targeted for spraying inner diameter (ID) and outer diameter (OD) engine components, respectively. The plasma torch hardware life was evaluated by torch cycle duration runs. Examples of highly strain-tolerant TBCs onto the ID and OD engine components were demonstrated, highlighting the wide versatility and process range of the SinplexPro.

This study is aimed to investigate the effect of SiO2/distilled (DI) water nanofluids on the heat transfer enhancement inside a circular mini-tube tube with an inner diameter (Di) = 0.8 mm. The flo...

In this work, a copper bromide laser with an active medium length of 58 cm and an inner diameter of 20 mm was designed and constructed. He and Ne were used as buffer gases. The effect of reservoir temperature, He and Ne buffer gas pressure, frequency and electrical input power on the output power were investigated. The result of experiments shows that an optimum laser efficiency was obtained at the electrical input power of 2.1kW and corresponding operational temperature of 510 oC. The maximum output powers, 4 and 6 W, with use of He and Ne buffer gases, were determined at pressures 11 and 24 torr, respectively.

In this study, quaternary ammonium functionalized-silica gel was synthesized for nitrate removal using dimethyl dodecyl[3-(trimethoxysilyl)propyl] ammonium chloride (DMDAC) as a quaternary ammonium silane coupling agent, which was grafted to silica gel to obtain the DMDAC-silica gel. Batch experiments showed that the DMDAC-silica gel could effectively remove nitrate in the pH range of 4 to 10. Kinetic and equilibrium experiments showed that nitrate removal by the DMDAC-silica gel reached equilibrium in 60 min with a maximum nitrate removal capacity of 56.4 mg/g. Fixed-bed column experiments (bed depth = 10–30 cm; inner diameter of column = 2.5 cm; flow rate = 0.06–0.18 L/h) in nitrate solution demonstrated the dynamic behaviors of nitrate removal by the DMDAC-silica gel under various experimental conditions of flow rate, bed depth, and influent nitrate concentration. The DMDAC-silica gels could be successfully used for nitrate removal and regenerated and reused with 10% NaCl solution in the column. In groundwater (nitrate = 140 mg/L, chloride = 63 mg/L, sulfate = 440 mg/L, and bicarbonate = 20–300 mg/L), the nitrate BTCs appeared behind the sulfate BTCs with α S N values of 5.7–11.3, indicating that the DMDAC-silica gel could selectively remove nitrate over sulfate in dynamic flow conditions.

Sample delivery using injectors is widely used in serial crystallography (SX) and has significantly contributed to the determination of crystal structures at room temperature. However, sophisticated injector nozzle fabrication methods and sample delivery operations have made it difficult for ordinary users to access the SX research. Herein, a simple and easily accessible sample delivery method for SX experiments is introduced, that uses a viscous medium, commercially available syringe and syringe pump. The syringe containing the lysozyme crystals embedded in lipidic cubic phase (LCP) or polyacrylamide (PAM) delivery media was connected to a needle having an inner diameter of 168 µm, after which it was installed on a syringe pump. By driving the syringe pump, the syringe plunger was pushed and the crystal sample was delivered to the X-ray beam position in a stable manner. Using this system, the room-temperature crystal structures of lysozyme embedded in LCP and PAM at 1.56 Å and 1.75 Å, respectively, were determined. This straightforward syringe pump-based sample delivery system can be utilized in SX.

The flow boiling heat transfer in a vertical pipe of inner diameter 7.5 mm was investigated with pure water and Al2O3/water nanofluid as working fluids. The main heater section was made up of borosilicate glass for better visualization of flow regime. For this study, particle concentrations of 0.001%, 0.005% and 0.01% were considered. The influence of mass flux and heat flux, on flow boiling heat transfer was analysed. From the results, it is observed that boiling heat transfer coefficient is increasing with mass flux for both water and nanofluids. Use of nanofluid decreases wall superheat. The average reduction of wall superheat, as compared to water, at mass flux of 905.42 kg/s-m2 for 0.001%, 0.005% and 0.01% nanofluids is 10.8%, 21.34% and 26.79% respectively. It is also observed that heat transfer coefficient increases with particle concentration due to the changed heater surface characteristics and amendment in bubble formation mechanism. The average enhancement in heat transfer coefficient, as compared to water, for the particle concentrations of 0.001%, 0.005% and 0.01% at a mass flux of 905.42 kg/s-m2 is found to be 12.11%, 21.75% and 27.97%, respectively. Flow visualization study was also done to differentiate flow patterns of water and nanofluids. Churn flow regime was observed for water at moderate heat fluxes. However, in case of nanofluids, churn flow was not observed. The flow boiling heat transfer coefficient is observed to be high for the nanofluids compared to water. An effort has been made to explain the heat transfer mechanism, based on the existing flow boiling regime under the given conditions.

The precise forming of inner hole has been a major technical difficulty in the cross wedge rolling (CWR) of hollow shaft. This paper proposes a new process to form hollow shafts with variable inner diameters by using the CWR with mandrel control. The forming characteristics and dimension precision of this process are analyzed by combining finite element modelling (FEM) and forming trials. The hole step of hollow shaft with variable inner diameter is formed in a spiral pattern. The helixes result in many micro-steps in hole step when forming the right-angle inner step. The metal flow lines demonstrated that mandrel step hindered the axial metal flow of inner hole and the metals were accumulated in hole step. The rolling load increases in the process of forming hole step. The mandrel is subjected to axial load when hole contacts the mandrel step. The roundness can be improved by reducing the mandrel diameter in knifing position. The axial accuracy of inner diameter can be classed as three parts: hole expansion, stable rolling, hole shrinkage. The compensated mandrel was designed to improve axial precision of inner diameter. The results showed that the inner hole dimension can be effectively controlled.

We have been developing a liquid-helium-free magnet using High-Temperature Superconducting (HTS) wire for MRI. The aim of this research and development is to commercialize a 3-T HTS magnet for whole body MRI which has the characteristics of being liquid-helium-free, small, and light-weight. HTS coil requires tolerance of a high magnetic field, 7 T, and it must have high current density, 200 A/mm 2 , for developing a small and light weight magnet used for 3-T MRI. A half-size 5-T HTS magnet will be manufactured in order to demonstrate the tolerance of high magnetic field and high current density of the coil, which are equivalent to a whole-body 3-T MRI magnet in a half-size HTS magnet. In this paper, we have investigated the arrangement of coils of a half-size 5-T coil. The designed coil consists of 124 double-pancake coils, whose inner diameter is 560 mm, outer diameter is 1200 mm, and axial length is 1100 mm. The uniformity of designed magnetic field is under 2.0 ppm (250 mmDSV).

REBCO coated conductor has been regarded as one of the most viable high-temperature superconductor (HTS) options for next-generation high field magnets, mainly owing to its large in-field current carrying capacity and higher mechanical strength. To explore REBCO coil technology, a small-scale REBCO coil was designed, fabricated and tested. The REBCO coil has a winding inner diameter of 15 mm, outer diameter of 29 mm and length of 38 mm using layer-wound and no-insulation technology. The REBCO coil was tested in a 31.5 T background field, leading to a high field of 32.5 T. The no-insulation behaviors of the REBCO coil, including the charging delay and magnet constant, were investigated at 77 K and 4.2 K respectively. With the magnetic load from the high fields, we found the REBCO coil was mechanically damaged after the experiments, being two major patterns: peeling and bucking.

As one speciality of the Swiss hydraulic engineering tradition, several torrent diversion schemes were undertaken dating from the 18th century, with the aim of using the natural lake as a retention basin. The recent project of flood protection of the lower Sihl valley and the City of Zurich features a gallery of 2.1km length with a 6.6m inner diameter designed for a 330m3/s free flow, discharging into Lake Zurich in an HQ500 event. After a short presentation of the main features of the project, the paper concentrates on the target construction pit of the TBM drive close to a major railway line at the built-up lakeside.

The hidden presence of fentanyl and new psychoactive substances in established illicit drugs has led to a great number of unintentional fatal overdoses, justifying the urgent need for portable tools for the rapid screening of various drugs. Ion mobility spectrometry, as a rapid detection technique, has been widely used in detecting illicit drugs, whereas it is insufficiently sensitive for bigger ions due to the mobility discrimination of an ion shutter. In this work, a miniaturized ion mobility spectrometer with an inner diameter of 14 mm and a drift length of 38.9 mm and equipped with a novel dual-compression tristate ion shutter has been developed, which could greatly reduce the mobility discrimination by compressing the ion packet twice during the injection process. The best gating performance of the dual-compression tristate ion shutter was about three times as high as that of the tristate ion shutter and twice as high as that of the Tyndall-Powell shutter. For example, the peak height was increased by 150 or 40% when the resolving power was the same, whereas the resolution of two neighboring peaks was improved by 46 or 19% when the peak heights were the same. In screening of fentanyl drug mixtures, the new shutter enhanced the identification accuracy of constituents by making peaks of slow dimer ions and complex ions observable. Besides, the new shutter helped to achieve high sensitivity for drug ions spreading a wide ion mobility range from 0.644 to 2.032 cm2 s-1 V-1, demonstrating its potential use in the analysis of other mixtures and the detection of large ions.

To be able to acquire the mixture velocity of water continuous oil-gas-water three-phase flow in 20-mm inner diameter small pipe based on the cross-correlation method (CCM), accurate measurement of the cross-correlation velocity, and establishing valid relationship between cross-correlation velocity and mixture velocity is of importance. Due to the severe slippage effect and the non-uniform distribution of phases in three-phase flow, the correlation between the upstream and downstream signals is seriously affected, and the relationship between the cross-correlation velocity and the mixture velocity is extremely complicated. Moreover, the low-sampling frequency and noise also reduce the accuracy of cross-correlation velocity measurement. In this paper, a cross-correlation flowmeter (CCFM) with two ring-shape conductance sensors embedded on the center body is proposed. Based on the finite element method (FEM), the geometry of the CCFM is designed and optimized. A novel fast Fourier transform (FFT) interpolation algorithm is investigated to increase the sampling frequency while eliminating the noise. Afterward, the performances of the CCFM and the FFT interpolation algorithm combined with the CCM are experimentally evaluated. The results show that the CCFM can enhance the correlation of upstream and downstream signals while FFT interpolation algorithm can effectively increase the sampling frequency and eliminate the noise, which can improve the accuracy of cross-correlation velocity measurement. The CCFM also can simplify the relationship between the cross-correlation velocity and mixture velocity, and thus the mixture velocity can be satisfactorily predicted.

Polymer grouting technology is a cost-effective and trenchless method for repairing leakage and subsidence of drainage pipelines. This paper reports the results of a full-scale experimental approach in the field, where we tested the structural dynamic responses, before and after polymer grouting trenchless repairing, of a reinforced concrete drainage pipeline of 700 mm inner diameter buried in dense soil and subjected to both surface impact loads and driving loads. The dynamic changes of three types of pipeline—the normal pipeline, disengaged pipeline, and polymer-repaired pipeline—is reported in detail in this paper for different soil cover depths, types and magnitudes of loads, and locations. The results show that under the surface load of the soil, the pipe experiences compression at its crown and bottom and tension at its springlines on both sides; moreover, the circumferential stress is greater than its longitudinal stress. An additional impact load or driving load has its greatest influence within 3 m on both sides of its point of action. The bell and spigot joints are the most vulnerable places in the pipeline. There the vertical displacement is discontinuous and relatively large when extra loads are applied. The dynamic response of the pipeline is greater to impact loads than to actual driving loads of comparable magnitude. Uneven pavement also enhances the response of a buried pipeline to the surface traffic load. Pipeline disengagement has a substantial negative effect on the overall mechanical resilience of the pipeline. However, polymer grouting can repair a disengaged pipeline effectively, even restoring its mechanical behavior to that of a normal pipeline.

Peristalsis is widely seen in nature, as this pumping action is important in digestive systems for conveying sustenance to every corner of the body. In this paper, we propose a muscle-powered tubular micro pump that provides peristaltic transport. We utilized Drosophila melanogaster larvae that express channelrhodopsin-2 (ChR2) on the cell membrane of skeletal muscles to obtain light-responsive muscle tissues. The larvae were forced to contract with blue light stimulation. While changing the speed of the propagating light stimulation, we observed displacement on the surface of the contractile muscle tissues. We obtained peristaltic pumps from the larvae by dissecting them into tubular structures. The average inner diameter of the tubular structures was about 400 μm and the average outer diameter was about 750 μm. Contractions of this tubular structure could be controlled with the same blue light stimulation. To make the inner flow visible, we placed microbeads into the peristaltic pump, and thus determined that the pump could transport microbeads at a speed of 120 μm·s−1. Keywords: Tubular structure, Bioactuator, Peristaltic pump, Optogenetics, Biomaterial, Muscle actuator, Tissue engineered, Soft robot

A new belt conveyor design providing the possibility of changing the conveyor belt cross section depending on the flow of transported bulk material has been proposed. A procedure for determining the load on the hold-down lever rotation mechanism is presented. A calculation of the value of equivalent load applied to the coupler (considering crimping) is provided, which allows selecting the inner diameter and trapezoidal thread parameters of the coupler, calculating the screw pair moments of resistance, and choose the appropriate size of the gear motor.

Wax deposits in oil pipelines can reduce the effective inner diameter of such pipelines, which may lead to pipeline blockage accidents. In this study, a cold finger experimental device was construc...

The flow condensation heat transfer performances of R1234ze(E) and R32 in a horizontal single circular minitube with the inner diameter of 2 mm are investigated experimentally. Tests are carried ou...

Positive flow characteristic is favorable in design of vertical water wall of large-scale once-through boilers, since it is beneficial for reducing potential temperature differences and thermal imbalance distribution across the water wall. The identification of the critical mass flux (G0) at which the flow characteristic transits from positive to negative is important for design of supercritical boilers with vertical water wall. In this paper, theoretical analysis was performed to investigate G0 under both supercritical and subcritical pressures. A theoretical solution of G0 was derived through thermal-hydraulic models. The impacts of operation parameters and tube structure parameters on G0 were quantified through numerical analysis. The results show that fluid outlet temperature, fluid pressure, tube inner diameter and tube friction factor have significant impacts on G0. G0 decreases as the increase of the fluid outlet temperature and the decrease of the fluid pressure. Under the condition of identical fluid inlet and outlet temperatures, operating pressure and tube length, G0 is proportional to D / λ . With the proposed model, G0 of a 600 MWe supercritical CFB boiler under different loads were calculated and validated.

We explore the temperature dependence of pressure-driven water permeation through membranes consisting of a vertically aligned double-walled carbon nanotube (VA DWCNT) array. The prepared membrane with CNT inner diameter of 3.9 nm exhibits no water permeation below the critical temperature of 26 °C, after which water permeability is first observed and increases with temperatures >26 °C. Further, the critical temperature decreases to 18 °C when the CNT inner diameter increases to 6.0 nm. The water permeation in the CNT-confined space exhibits activation energy transitions around room temperature, thereby suggesting that the confined water molecules in CNTs exhibit plural ordered structures.

Kaolinite nanotubes (KNTs) were synthesized successfully from raw well crystalline kaolinite and characterized using different analytical techniques. The synthetic tubes appear as multi-walled scrolls with length ranges from 50 nm to 600 nm with an average pore diameter of 12 nm and specific surface area of 105m2/g. The outer diameter range of kaolinite tubes from 10 nm to 50 nm, and the inner diameter range from about 2 to about 20 nm. The synthetic kaolinite nanotubes were used as Nano-carriers for 5-fluorouracil (5FU) with encapsulation capacity reach about 103 mg/g which was confirmed by HRTEM, FT-IR and XRD analysis for the samples after the loading process. The synthetic KNTs loaded by 5FU (KNTs/5FU) is of controlled release properties that continued to about 60 h at releasing percentage of about 74.3% and 91% using intestinal fluid and colonic fluid, respectively. The cell viability studies utilizing L929 cells line resulted in very high cell viability percentage and non-cytotoxicity induced the application of KNTs as a promising carrier for 5FU of effective anticancer properties.

A liquid membrane in Taylor flow regime is a novel alternative kind of contact in three-phase flow for liquid membranes that preserves the advantages of conventional emulsion liquid membranes while overcomes the stability problems of emulsion systems. As a proof of concept, this work presents experimental results of a liquid membrane in Taylor flow for lactic acid removal. Several operating conditions, such as injection times, delay times and flow of the membrane phase were tested for a channel length and inner diameter of 348.8 cm and 2.5 mm, respectively. The lactic acid removal is mainly affected by the driving force of lactic acid concentrations between donor droplets and the membrane interface, and the space-time. Thus, the lactic acid removal process through the liquid membrane in Taylor flow is enhanced at low injection times and high droplet velocity considering that enough space-time is provided. This technology results promising as an alternative to conventional liquid membranes and the intensification of chemical and fermentative processes.

In this study, the explosion behaviors of methane-air mixtures were investigated experimentally in a cylinder vessel (210 mm inner diameter and 210 mm height) filled with a single orifice plate at atmospheric pressure (1 atm) and room temperature (298 K). The equivalence ratios of the test mixtures ranged from 0.7 to 1.3. The blockage ratios of the orifice plates were from 0.49 to 0.94, and the distance between the orifice plates and the ignition point ( S ) were 25 mm, 50 mm and 75 mm. The results show that the maximum explosion pressure in the presence of an orifice plate. However, the effects of the orifice plate on the maximum rate of pressure rise are various. At the fuel-lean side, the maximum pressure rise rate is increased significantly (larger than that of the stoichiometric condition). As the distance between the orifice plate and ignitor increases, the maximum pressure rise rate increases. In the case of the fuel-rich conditions, the maximum pressure rise rate is the smallest for S = 25 mm, followed by the no plate condition, S = 50 mm and S = 75 mm. The mechanisms are left for further study.

The metal content of tube bundles of rigid-type shell-and-tube heat exchangers is analyzed in terms of their design options and used materials. Outer tube diameters, tube material, wall thickness, pressure in the tubes, and inner diameter of the exchanger are considered as the influencing factors. Use of tube bundles consisting of strong tubes is proposed for reducing metal content of tube bundles. High-strength low-alloy steel tubes are recommended for medium and high pressures in the tubes. In the case of low pressure in the tubes, the difference in metal content of carbon steel and high-strength low-alloy steel tube bundles is negligible.

This paper studies the effect of various arrangements of circular rings on thermal performance in a circular tube. A wall attached circular rings were configured with the different inner diameter t...

Background The ACURATE neo prosthesis is commonly implanted using introducer sheaths with inner diameters of up to 20 French. The use of only the expandable mesh component of the transGlide introducer system (Meshonly) would substantially decrease the inner diameter to 13 French. We sought to assess the feasibility and safety of using Meshonly for femoral access of the ACURATE neo device and to compare outcomes with patients in whom standard sheaths were used. Methods and results We retrospectively analyzed a total of 551 patients with severe aortic stenosis from 4 high volume centers in Germany and Switzerland undergoing transfemoral TAVI between February 2016 and February 2018 with implantation of the ACURATE neo device. The median age was 81.7 [78.3–85.2], 67.0% were female, the STS score was 4.2% [2.8–6.5]. The use of the Meshonly was feasible in all attempted cases (n = 272); in all other patients, a standard sheath was used. Major vascular complications at the main access-site (VARC-2) were less frequent in the Meshonly group than in the standard sheath group (1.5% vs. 7.9%; p Conclusions Transfemoral implantation of the ACURATE neo device using the Meshonly was associated with a lower rate of major access-related complications when compared to the standard of care.

The inner diameter is an important parameter in the design and fabrication of monocapillary X-ray optics which is widely used in X-ray technology. The confocal X-ray fluorescence (CXRF) based on X-ray capillary optics was proposed to nondestructively measure the inner diameter of the monocapillary. The zinc chlorine solutions were filled into monocapillary in order to measure its inner diameter with the CXRF. With a scan of the edge of zinc solutions in a monocapillary optic through the confocal volume of the CXRF, the inner diameter could be obtained directly and nondestructively. The mean of relative errors of this method for measuring the inner diameter were approximately 4.1%. This proposed method of determining the inner diameter of monocapillary optics plays a significant role in design, fabrication and application of the monocapillary X-ray optics.

Traditional photoacoustic (PA) images are formed from the amplitudes of the envelope-detected PA data. This approach largely ignores encoded spectral information that may provide more insight about tissue function and pathology. Here we introduce a new PA graphic equalization (PAGE) algorithm that divides the PA signal into a collection of frequency bands that are related to different-sized optical absorbers. Radiofrequency (RF) PA data were obtained using a Vevo 3100 with LAZR-X system (Fujifilm VisualSonics Inc). Experiments were performed using phantom materials and narrow translucent silicone tubes with clotting blood (inner diameter of 0.30, 0.51, or 0.64 mm). Phantoms were created by embedding an agar solution with fluorescent microspheres having diameters of 10 to 45 µm or 106 to 125 µm. Overall, preliminary in vitro results demonstrate that PAGE processing can distinguish micrometer-sized optical absorbers of varying size.

With the widespread use of substations around the world, oil jet fire accidents from transformer oil-filled equipment in substations caused by faults have occurred from time to time. In this paper, a series of transformer oil jet fire experiments are carried out by changing the external heat source (30 cm and 40 cm) and the inner diameter of the container (5 cm, 8 cm and 10 cm) to study the axial centerline temperature distribution of the transformer oil jet fire plume of the transformer oil-filled equipment in the substation. The experiment uses K-type thermocouple, electronic balance and CCD to measure and assess the temperature distribution of the axial centerline of the fire plume of the transformer oil jet. The result demonstrates that the axial centerline temperature of the fire plume increases with the external heat release rate and the inner diameter of the container. In addition, a novel axial temperature distribution prediction model of the transformer oil jet fire plume is established. This model can effectively predict the oil jet fire plume temperature of transformer oil- filling equipment in substations, and provide help for substation fire control.

Vertically aligned Fe, S, and Fe-S doped anatase TiO2 nanotube arrays are prepared by electrochemical anodization process using an organic electrolyte in which lactic acid is added as an additive. In the electrolyte, nanotube layers of greater length (12 μm) and high order with inner diameter of approx. 90 nm and outer diameter of approx. 170 nm are achieved. Doping of Fe, S, and Fe-S via simple wet impregnation method substituted Ti and O sites with Fe and S, which leads to enhance the rate performance at high discharge current densities. Discharge capacities of TiO2 tubes increased from 82 mAh g-1 (bare) to 165 mAh g-1 for Fe-S doped TiO2 at high current densities of 0.3 mAcm-2 after 100 cycles with exceptional capacity retention of 85% after 100 cycles. Owing to the enhancement of thermodynamic and kinetic properties by doping of Fe-S, Li-diffusion increas2ed resulting in remarkable discharge capacities of 143 mAh g-1 and 89 mAh g-1 at a current density of 7.4 mA cm-2 and 19 mA cm-2, respectively.

Background Recent introduction of large bore aspiration catheters have contributed to high reperfusion rates. The alteration of these catheters to have angled tips, which increase clot engagement area by approximately 15%, has been suggested to improve rates of complete clot ingestion, resulting in higher quality thrombectomies. We aimed to evaluate the recanalization efficacy of new generation angled tip aspiration catheters in comparison to commonly used straight tip aspiration catheters in real world data set. Methods We performed a multicenter retrospective analysis of consecutive acute ischemic stroke patients with M1 occlusion treated within 24 hours from the time of last known well. Patients were divided into two cohorts: those in whom a 0.071 angled tip catheter was the initial device used to attempt reperfusion and those in whom a 0.064-0.074 inch flat tip (non-angled) catheter was the initial device used to attempt reperfusion. The primary outcome was the rate of excellent reperfusion (TICI 2C). Secondary outcomes included the rate of successful reperfusion (TICI2B), use of stent retrievers, and access to successful reperfusion time. All data was self-adjudicated. No outside funding was provided for this analysis. Results Total of 650 patients with acute M1 occlusion who underwent thrombectomy were identified. Angled tip Zoom 71 catheter was used in 162 patients, while 488 patients were treated with flat tip aspiration catheters (ranging 0.064 to 0.074 inch in inner diameter). The baseline mRS score, admission NIHSS score, the rate of intravenous thrombolytic therapy, symptom onset to hospital arrival, and use of anesthesia were not different between the cohorts. The primary outcome was significantly higher in the angled tip cohort (67% vs 59%, p=0.03). There was no difference in the rate of TICI2B reperfusion (96% vs 94%, p=0.71). There was a lower rate of stent retriever use (25% vs 44%, p Conclusion This multicenter, consecutive real-world experience demonstrates that M1 thrombectomy with an angled tip aspiration catheter is associated with higher rates of TICI 2C or better reperfusion, equal rates of TICI 2B or better reperfusion, and faster time to successful reperfusion. Disclosures J. Vargas: None. S. Majidi: None. H. Hawk: None. S. Nimjee: None. A. Zakeri: None. M. Mokin: None. R. Kellogg: None. G. Cortez: None. A. Aghaebrahim: None. E. Sauvageau: None. R. Hanel: None. R. De Leacy: None. A. Siddiqui: None. A. Turk: None. M. Oselkin: None. E. Marlin: None. R. Turner: None. I. Chaudry: None. J. Milburn: None.

Background Several reports have demonstrated significant clinical benefits with transradial access compared to transfemoral access for endovascular procedures. Despite this, the transradial technique for neurointerventions is underutilized due to the anatomical complexities that may affect a successful procedure using conventional access catheter technology. The purpose of this single-center study was to evaluate the feasibility and safety of next generation large-bore intracranial guide catheters (0.088” inner diameter, 8Fr) using a transradial approach (TRA) in carefully selected patients undergoing neurointerventions. Methods The retrospective review of the institutional, IRB-approved database was undertaken to find cases where the TracStar LDP™ or Zoom™ 88 guide catheters (Imperative Care, Campbell, CA) were used with a TRA for neurointerventions. For this study, gender, age, case type, target anatomy, distal location reached with the guide catheters, time from access to reperfusion, complications, and the Thrombolysis in Cerebral Infarction (TICI) score were collected. Safe placement of the guide catheters to the target anatomy was considered a technical success. Results From August 2020 to March 2021, 13 patients underwent TRA neurointerventions using the TracStar LDP or Zoom 88 guide catheters. The TracStar LDP was used in 77% (10/13) of patients; the Zoom 88 guide catheter was used in 23% (3/13) of patients. The type of intervention was acute ischemic stroke in 69% (9/13) of patients and aneurysm embolization in 31% (4/13) of patients. The TracStar LDP facilitated the implantation of flow diverters in all aneurysm cases with 75% (3/4) using a biaxial system. Overall, there was an even distribution between females (54%, 7/13) and males (46%, 6/13). The median age was 72.5 (range=48-88) years. Most patients with aneurysms were females (75%, 3/4); this population’s median age was 58.5 (range=54-64) years. In patients with acute ischemic stroke, the median age was 76 (range=48-88) years. The target anatomy for all aneurysm patients was the left internal carotid artery. The target anatomy for stroke patients included right internal carotid artery in 77.8% (7/9) of patients, left internal carotid artery in 11.1% (1/9) of patients and left vertebral artery in 11.1% (1/9) of patients. In these patients, the final positions of the guide catheters included Supraclinoid Carotid (n=2), Ophthalmic segment (n=2), Petrous Carotid, Petro-Cavernous junction, Basilar, Cavernous-Carotid, and in one case the Zoom 88 was positioned in the right M1. The median puncture to reperfusion time was 30.5 (range=5-50) minutes. The TICI 2b or greater was achieved in 77.8% (7/9) of patients. There were no complications associated with the guide catheters. In two patients (one stroke, one aneurysm), the TracStar LDP guide catheter was used successfully as the rescue option after the initial approach with the 0.079” radial guide catheter failed. Conclusion Transradial access with the TracStar LDP and Zoom 88 large-bore guide catheters is feasible and safe in achieving intracranial access for neurointerventions in carefully selected patients. Disclosures L. Lyons: None. M. Abouelleil: None. A. Restrepo Orozco: None. L. Verhey: None. J. Tsai: 2; C; Cerenovus, Medtronic. P. Mazaris: 2; C; Stryker. J. Singer: 2; C; Medtronic, Cerenovus, Stryker, Pneumbra, Nico.

Background Increasing the distal ID of aspiration catheters has been associated with higher quality and faster thrombectomies, due to a presumed higher rate of complete clot ingestion. We aimed to evaluate the recanalization efficacy of newer generation, larger bore aspiration catheters versus smaller distal ID aspiration catheters in a real world data set. Methods We performed a multicenter retrospective analysis of consecutive acute ischemic stroke patients with M1 occlusion treated within 24 hours from the time of last known well. Patients were divided into two groups based on the distal inner diameter of the aspiration catheter used for reperfusion: 0.070’ or greater (large) and 0.068’ or smaller sized catheters (small). The primary outcome was the rate of TICI 2C or better reperfusion. Secondary outcomes included the rate of TICI 2B or better reperfusion, rate of recanalization on first pass, and access to successful reperfusion time. All data was self-adjudicated. No outside funding was provided for this analysis. Results Total of 774 patients with acute M1 occlusion who underwent thrombectomy with an aspiration catheter. Larger bore catheters (with a distal ID of 0.070’ to 0.074’) were used in 421 patients, while 353 patients were treated with small aspiration catheters (distal ID of 0.060 to 0.068’). There was no significant difference in the rate of TICI 2B or better (94.5 vs 94.3%, p=0.909), TICI 2C or better (62.1% vs 59.5%, p=0.451), and TICI 3 recanalization (47.6% vs 51.3%, p=0.311) between groups. However, there the larger catheter group had a significantly improved rate of first pass TICI 2C or better (46.8% vs 38.2%, p=0.017), and access time to final recanalization (20.1 minutes vs 23.1 minutes, p Conclusion This multicenter, consecutive real-world experience demonstrates that M1 thrombectomy with a larger distal ID catheter is associated with faster time to recanalization and higher rate of TICI 2C or better recanalization on first pass, but also with a higher rate of hemorrhage on follow up imaging. Disclosures J. Vargas: 2; C; Cerenovus. 4; C; Truvic. S. Majidi: None. G. Cortez: None. A. Aghaebrahmin: None. E. Sauvageau: None. R. Hanel: 1; C; Microvention, Stryker. 2; C; Stryker, Medtronic, Cerenovus, Balt, Q’APel. 4; C; Rist. 6; C; MiVI. H. Hawk: None. S. Nimjee: None. A. Zakeri: None. M. Mokin: 2; C; Medtronic, Cerenovus. C. Chen: None. R. Kellogg: None. A. Turk: 2; C; Stryker, Balt, Cerenovus, Medtronic, Q’APel, Imperitive Care. 4; C; Imperitive Care. R. Deleacy: None. A. Siddiqui: 2; C; Imperitive Care, Stryker, Medtronic, Microvention, Penumbra. 4; C; Imperitive Care, Truvic. M. Oselkin: None. E. Marlin: None. R. TUrner: 2; C; Siemens, Cerenovus, Q’APel. 4; C; Q’APel. I. Chaudry: 2; C; Cerenovus, Medtronic, Q’APel. 4; C; Q’APel. J. Milburn: None.

Wheezing is often occurred in infants and young children with respiratory infections. For children with recurrent wheezing, after controlling their wheezing, they should be alert to rare diseases. Here, We report a case of wheezing following the application of the patent ductus arteriosus occlusion device ADOII (AGA Medical Corporation, Golden Valley,MN) with the occlusion device pressing against the inner diameter of the adjacent left main bronchus. After the pressure end of the occluder was removed, the child’s wheezing was effectively relieved

In this paper, based on the automatic detection of robot, a three-claw positioning structure is designed by using threepoint positioning technology. It can accurately locate the center position of the long and thick wall tubular equipment. According to the principle of three-point positioning technology, a kind of inner diameter measuring structure of long and thick wall tubular equipment is designed, so as to realize the accurate positioning and accurate measurement of long and thick wall tubular equipment.

Introduction: Valve-in-valve TAVR (ViV-TAVR) is an established treatment for failing surgical aortic valves in patient at high surgical risk. Elevated transprosthetic gradients are common after ViV-TAVR. Previously, bench tests showed feasibility of bioprosthetic valve fracturing (VF) using high-pressure balloons. Small case series show reduced transprosthetic gradients using VF. We present our clinical experience and outcome of VF.Material and Methods: Consecutive ViV-TAVR patients were identified from our institutional TAVR database and utilization of bioprosthetic valve fracturing or intraprocedural postdilatation was reviewed. Surgical valves were categorized as responsive or not responsive to VF. Transprosthetic gradients were compared in procedures with VF and procedures with or without postdilatation.Results: In 67 consecutive ViV-TAVR procedures between January 2018 and September 2020, VF was attempted in 15 cases with eight being successful. Standard postdilatation was performed in 21 patients and 31 cases were without postdilatation. Mean transprosthetic gradients (MPG) decreased from 34.2 + 12.5 to 12.7 + 7.4 mmHg (p < 0.001) for all patients. MPG was 8.6 + 3.5 mmHg after VF, 12.9 + 8.5 mmHg after standard postdilatation (p = 0.18) and 13.4 + 6.8 mmHg in cases without postdilatation (p = 0.04). In small surgical valves with true inner diameter p = 0.068) and 16.2 + 9.2 mmHg without postdilatation (p = 0.152). Failed attempts with BVF occurred with the Perimount standard valve.Conclusion: Bioprosthetic valve fracturing results in lower mean transprosthetic gradients after ViV-TAVR. Responsiveness of BVF in Perimount surgical valves, long-term hemodynamic outcome, and potential survival benefits need further evaluation.

Purpose. To analyze clinical parameters of two subtypes of lamellar macular hole (LMH): degenerative and tractional. Methods. This retrospective chart review study included patients monitored for more than 6 months after the initial diagnosis of LMH from January 2011 to January 2018. LMH was classified in two subtypes: degenerative and tractional. The following parameters between both subtypes were assessed: central subfield thickness (CST), maximum inner diameter (MID), maximum outer diameter (MOD), MID/MOD ratio, inner and outer segment (IS/OS) junction disruption, residual retinal thickness (RRT), subfoveal choroidal thickness (SFCT), best-corrected visual acuity (BCVA), anatomical progression rate, and percentage of patients undergoing surgery. Results. This study included 51 eyes with a mean follow-up period of 18.94 months: 33 eyes with tractional LMH and 18 eyes with degenerative LMH. MID was not significantly different between both subtypes but MOD was significantly greater in tractional LMH than degenerative types (tractional, 1131.6 μm; degenerative, 708.9 μm; p p p = 0.010). The SFCT was correlated to anatomical progression in the tractional LMH (correlation coefficient = 0.351, p = 0.049) but not in the degenerative LMH. During the follow-up period, 4 eyes (22.2%) of the degenerative LMH and 11 eyes (33.3%) of the tractional LMH underwent surgery. Conclusions. We found that greater SFCT at baseline was correlated to anatomical progression of tractional LMH. Therefore, it is expected that SFCT could be used as a biomarker to predict anatomical progression in tractional LMH.

The precision forming of inner hole is one of technological bottlenecks in Cross-wedge Rolling (CWR) of hollow shaft with mandrel. The inner diameters show signs of characteristic fluctuation despite under the control of mandrel. The uniformity of inner diameter was investigated by finite element simulation and experiments in this study. The inner hole expands at the knifing stage and shrinks at the sizing stage. The dimensional fluctuation of inner diameter is mainly resulting from the improper metal flow. The radial and axial metal flows are insufficient at the knifing stage, which resulting in the hole expansion at knifing zone. The hole shrinkage is caused by the relatively adequate radial metal flow at sizing stage. The experiment results show that the hole expansion increases with the increasing stretching angle and mandrel diameter and decreases with the increasing forming angle and initial wall thickness. The hole expansion first increases and then decreases with the increasing reduction ratio. The hole shrinkage has positive correlations with forming angle, reduction ratio and initial wall thickness, and negatively correlates with stretching angle and relative mandrel diameter. A modified CWR roll with the curved-surface knife is proposed to get rid of the hole expansion. Based on experiments and simulations, the most suitable geometric parameters of the curved-surface knife are determined. Using mandrel diameter compensation can reduce the phenomenon of hole shrinkage. These methods were applied to the trial rolling of a half-shaft sleeve part, and the results show that the methods significantly restrain the inner diameter fluctuation.

Electrodes are basic components of C4D (capacitively coupled contactless conductivity detection) sensors, and different electrode structures (the configuration pattern or the electrode geometry) can lead to different measurement results. In this work, the effects of electrode geometry of radial configuration on the measurement performance of C4D sensors are investigated. Two geometrical parameters, the electrode length and the electrode angle, are considered. A FEM (finite element method) model based on the C4D method is developed. With the FEM model, corresponding simulation results of conductivity measurement with different electrode geometry are obtained. Meanwhile, practical experiments of conductivity measurement are also conducted. According to the simulation results and experimental results, the optimal electrode geometry of the C4D sensor with radial configuration is discussed and proposed. The recommended electrode length is 5–10 times of the pipe inner diameter and the recommended electrode angle is 120–160°.

The slip velocity between phases is an important parameter for evaluating the volumetric flow rate of each phase in vertical pipes. This paper presents an improved empirical correction for calculating the slip velocity of two-phase, oil-water bubble flows in large-diameter vertical pipes, based on a series of experimental tests. Water holdup data were obtained through experiments on an oil-water mixture flowing through a transparent test section in a 16-m-long vertical pipe with an inner diameter of 124 mm. The water holdup ranged from 0.58 to 1, and the observed flow pattern was bubble flow. Based on these experimental data, a modified correction was developed to improve the accuracy of the prediction of slip velocity for oil-water bubble flow systems. In addition, the proposed correction was validated against published experimental data for pipes with diameters of 2–6 in. The performance of the proposed correction against an experimental dataset (from our tests and published data) was also compared with that of six other, widely accepted corrections. The proposed correction predicted the slip velocity of two-phase, oil-water bubble flow in large-diameter vertical pipes more accurately than previous corrections did.

The characteristics of each scoring balloon seem to be different because material or configuration of scoring element in each device is unique. The aim of this study is to clarify the difference of scoring effect among 3 different scoring devices. We prepared 3 different scoring devices [Wolverine™ Cutting Balloon™ (CB), ScoreFlex™ NC (SF), NSE Alpha™ (NSE), n = 5 respectively. Balloon diameter is 3 mm and 2 types of silicone tubes with different elasticity [140 kPa (tube S) and 576 kPa (tube H), respectively. Inner diameter is 3 mm]. We dilated each balloon in each silicone tube with nominal pressure (NP) and 20 atmosphere (HP) and took a picture using a micro CT. We measured penetration depth of all scoring elements into silicone tube wall and calculated their percentage using the following formula; penetration depth/original scoring element height × 100. We also observed the deformation of scoring element during balloon inflation in each device. Scoring element of CB cut deeper into both tubes significantly than SF and NSE at both pressure (40.5% vs 25.1% and 16.8% at NP and 86.1% vs 33.5% and 29.1% at HP in tube S, p

We read with great interest the recent paper by Li et al , which concluded that the tip of an aspiration catheter can expand to 115–125% of its original inner diameter (ID) when corked by a clot analog, creating an ‘aspiration force’ 61–99% higher than the theoretical value based on the labelled ID.1 We want to congratulate the authors on this novel finding, but also want to respectfully present our disagreement on the method to quantify the expansion of catheter tip ID and the interpretation of the measured force. The authors hypothesized that firm clots, when being aspirated into soft aspiration catheters, may actually expand the catheter tips. If correct, this expansion would lead to enhanced aspiration force, which is proportional to tip area, and thus potentially increase efficacy of clot extraction. However, instead of directly measuring catheter tip diameter when aspirating firm clots, the authors applied an indirect measure of tip area using a stiff cone-shaped 3D-printed resin clot analog. First, the authors measured the force required to …

Here, we report two cases involving a neonate and child in which a slip joint section was used to thread a Fogarty catheter into the endotracheal tube for one-lung ventilation (OLV). Both the neonate and infant required OLV, and were placed under general anesthesia. A Fogarty catheter was used for OLV. The Fogarty catheter was passed into the intraluminal side of the endotracheal tube through a slip joint section. OLV was maintained successfully without severe air leakage or Fogarty catheter displacement. The neonate had been intubated pre-operatively with a 3.5-mm inner diameter endotracheal tube, and we used that tube. These cases indicate that the technique can be applied to pre-operatively intubated patients and does not require surgeons to exchange endotracheal tubes. Use of the slip joint section technique facilitates Fogarty catheter fixation without additional dead space. J. Med. Invest. 68 : 209-212, February, 2021.

A seed-loading device was designed and modeled using the Monte Carlo method to verify the biological effect of iodine-125 (125I) particles on blood vessels through animal experiments. The dose distribution characteristics of irradiated vessels were established by adjusting the design variables and geometry. The deviation between the actual value and the theoretical value was verified in vitro by the thermoluminescence dosimetry (TLD) method. After verification, the device was used to examine the biological effect of 125I irradiation of canine carotid arteries in two dogs (and one control dog) for 180 days. The hollow cylinder seed-loading device was constructed with an inner diameter of 0.5 cm and a length of 3.3 cm. When six seeds were loaded into a single layer, the source strength ratio of the intermediate layer to the edge layer was 0.7:1. When six layers of seeds were arranged at 0.45-cm intervals, the deviations between the maximum, minimum and mean energy fluence within 2.25 cm of the vessel wall were 2.19% and -4.12%, respectively, and -9% and 4%, respectively, when verified in vitro using TLD. The carotid arteries showed good tolerance to 0.56 kGy (range of 0.51-0.58 kGy) after 180 days of irradiation. In conclusion, this 125I seed-loading device overcomes the random distribution of seeds and lays an accurate radiophysical foundation for subsequent biological experiments. The preliminary results showed that the carotid artery has good tolerance to 0.56 kGy irradiation.

Background: The aim of this study was to evaluate the quantitative morphological changes in lamellar macular holes (LMHs) based on SD-OCT examinations and to assess the correlations among minimal retinal thickness (MRT), reading vision (RV), and best corrected visual acuity (BCVA) over a 36-month follow-up period. Methods: A group of 40 patients (44 eyes) with LMH was evaluated, with an average age of 69.87 (SD = 10.14). The quantitative parameters monitored in the follow-up period (at 0, 3, 6, 12, 18, 24, 30, and 36 months) were tested for normality of distribution by Shapiro–Wilk and Kolmogorov–Smirnov tests. Results: The RV and BCVA values were stable, and no significant changes were found at any of the check-ups during the 36-month follow-up period (BCVA p = 0.435 and RV p = 0.0999). The analysis of individual quantitative LMH parameters during the 36-month follow-up period did not demonstrate statistically significant differences: MRT (p = 0.461), Max RT temporal (p = 0.051), Max RT nasal (p = 0.364), inner diameter (ID) (p = 0.089), and outer diameter (OD) (p = 0.985). Conclusions: The observations at 0, 6, 12, 18, 24, 30, and 36 months revealed moderate and significant correlations between RV and MRT. No significant correlation between BCVA and MRT was observed.

Difficult airway management (DAM) in neonates and infants requires anesthesiologists and critical care clinicians to respond rapidly with appropriate evaluation of specific situations. Therefore, organizing information regarding DAM devices and device-oriented guidance for neonate and infant DAM treatment will help practitioners select the safest and most effective strategy. Based on DAM device information and reported literature, there are three modern options for DAM in neonates and infants that can be selected according to the anatomical difficulty and device-oriented strategy: (1) video laryngoscope (VLS), (2) supraglottic airway device (SAD), and (3) flexible fiberoptic scope (FOS). Some VLSs are equipped with small blades for infants. Advanced SADs have small sizes for infants, and some effectively function as conduits for endotracheal intubation. The smallest FOS has an outer diameter of 2.2 mm and enables intubation with endotracheal tubes with an inner diameter of 3.0 mm. DAM in neonates and infants can be improved by effectively selecting the appropriate device combination and ensuring that available providers have the necessary skills.