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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.

Inner-diameter slicing based on a thin inner-diameter saw blade is one of the main hard and brittle material slicing methods. The inner-diameter saw blade needs to be tensioned for increasing its slicing stiffness and stability before working, and the tensioning quality affects the performance of subsequent material slicing directly and severely. In this paper, through finite element theoretical simulation and specialized experimental testing, the tensioning operation schemes are investigated systematically in the view of tensioning state and quality of the inner-diameter saw blade. By including mechanical equipment and electrical instruments, a specialized automatic experiment system is designed and manufactured with control and measurement function. Effects of bolts pre-tightening force, tightening sequence and rounds, and tensioning amount on the inner-diameter saw blade cutting-edge unevenness, lateral thrust stiffness, and transversal vibration response are investigated by theoretical simulation and experimental observation. A guideline on the optimization and improvement of initial tensioning is proposed for the inner-diameter saw blade practical engineering production.

Determination of liquefaction potential of sands in laboratory; dynamic three axial, hollow cylindrical torsional shear, resonance column, bender elements and cyclic simple shear tests are used. In this study, the effect of sample size on the determination of liquefaction energy of sandy soils in cyclic simple shear test apparatus was investigated. Uniform clean sea sand was used in the study. The cell inner diameter in which the samples to be tested is placed is 50 mm. Samples were prepared three different sizes with a length/diameter (H/D) ratio of 1, 0.5 and 0.25 and four varied relative densities (Dr: 40%, 50%, 60% and 70%). The samples were subjected to 1D cyclic loading at a frequency of 0.1 Hz under 100 kPa vertical stress and 50 kPa pore pressure. Each experiment was repeated 3 times, with equivalent or closer results considered significant. According to the test results, the liquefaction energy values per volume (J/m3) of the samples of different sizes are different from each other.

Aim This study was designed to evaluate a new technique for a completely diverting tube ileostomy achieved through temporary occlusion of the distal ileum using a flexible rubber strip. Methods This prospective interventional study was conducted in one centre. Patients who underwent colorectal resections with a primary anastomosis and who were deemed as requiring a defunctioning stoma were included in the study. After completion of resection and anastomosis, the tube ileostomy was fashioned by inserting a reinforced (spiral) endotracheal tube with an inner diameter of 7.5 mm into the ileum. To provide complete faecal diversion, temporary occlusion of the distal ileum was performed using a flexible rubber strip. The primary outcome of this study was the incidence of complete diversion achieved using this method. Results Fifty consecutive patients underwent a diverted tube ileostomy using the technique described above. Defaecation before removal of the strip did not occur in any of the patients inferring that complete diversion was observed in all patients (100%). The tube was removed at postoperative week 3. After tube removal, the resulting enterocutaneous fistulas closed spontaneously in a median of 6 (2-30) days. Conclusion The diverting tube ileostomy technique using an easily removable rubber strip to defunction the colorectal anastomosis is a safe and effective method that precludes the need to fashion a stoma.

This paper presents a novel study on the performance of closed-loop oscillating heat pipe (CLOHP) using iron oxide (Fe3O4) as the working fluid for three types of condensers. The tested CLOHP consists of six turns made of copper tubes, 4.5 mm outer diameter and 3 mm inner diameter with heating power input in a range of 0–200 W. The experimental results showed that the thermal performance of the CLOHPs has been improved when the corrugated horizontal condenser was used compare to straight and corrugated vertical condensers. Based on 800 sets of available experimental data, the results show that the CLOHPs with corrugated horizontal condenser had better thermal performance when charged with Fe3O4/water at 2% mass concentration.

Experimental research on a swirl-vane gas–liquid separator has been conducted with the aim to explore its application in downhole gas–water separation systems. With the help of a high-speed camera, the effect of gas content, Reynolds number and flow conditioning elements on the separation performance were investigated. The change of flow pattern will lead to the oscillation of air core inside the separator, which has significant influence on the separation performance. Experimental results show that both the increase of Reynolds number and the arranging of flow conditioning elements can only restrain the oscillation of air core to a certain degree. In addition, according to the evolution of air core, the flow pattern can be divided into: rod air core flow, tadpole-shaped air core flow, oscillating air core flow and swirling annular flow. Compared with the gas–liquid flow pattern map in vertical tube with the same inner diameter, it can be found that the flow pattern of gas–liquid mixture before entering the separator has significant influence on the state of the air core. In the end, the operational envelope limits of the separator were determined experimentally. Due to the effect of flow pattern, the separator is more suitable to be operated at low gas content. This research leads to a better understanding of hydraulic characteristics in this kind of separator.

Small-bore needles reduce the complications associated with soft tissue filler injection. Gel particles must be sized appropriately to pass through fine-bore needles with an acceptable extrusion force. However, most soft tissue filler particles are larger than the inner diameter of the needle. The authors hypothesized that the physical properties of these particles change as the gel passes through the needle.The authors aimed to investigate whether the predesigned physical and rheological properties of the filler change after passage through the small-bore needle.Particle sizes of 4 hyaluronic acid (HA) fillers were analyzed using a particle size analyzer. Five soft tissue fillers with different particle sizes were subjected to rheological characterization. All tests were performed using fillers with and without a 30-G needle.Monophasic HA fillers with smaller particle sizes exhibited small changes between particle sizes but no differences in rheological properties. Biphasic HA fillers with larger particle sizes exhibited remarkable changes in particle size and rheological properties. Calcium fillers exhibited changes in rheological properties.Injection through small-bore needles can alter the physical properties and rheological equilibrium of soft tissue fillers. The authors suggest avoiding small-bore needles as they may affect the rheological equilibrium and clinical performance of fillers.

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.

The Orbitrap is now a core component of several different instruments. However, evaluating the capabilities of each system is lacking in the field. Here, we compared the performance of multidimensional protein identification (MudPIT) on Velos Pro Orbitrap and Velos Orbitrap Elite mass spectrometers to reversed phase liquid chromatography (RPLC) on a Q-Exactive Plus and an Orbitrap Fusion Lumos. Using HeLa cell protein digests, we carried out triplicate analyses of 16 different chromatography conditions on four different instrumentation platforms. We first optimized RPLC conditions by varying column lengths, inner diameters, and particle sizes. We found that smaller particle sizes improve results but only with smaller inner diameter microcapillary columns. We then selected one chromatography condition on each system and varied gradients lengths. We used distributed normalized spectral abundance factor (dNSAF) values to determine quantitative reproducibility. With Pearson Product-Moment Correlation Coefficients r values routinely above 0.96, single RPLC on both the QE+ and Orbitrap Lumos outperformed MudPIT on the Orbitrap Elite mass spectrometer. In addition, when comparing dNSAF values measured for the same proteins across the different platforms, RPLC on the Orbitrap Lumos had greater sensitivity than MudPIT, as demonstrated by the detection and quantification of histone deacetylase complex components. Data are available via ProteomeXchange with identifier 10.6019/PXD009875.

We propose a method for eddy-current testing of the inner diameter of electroconductive pipes. The design of an eddy current transducer is described, as well as an algorithm for converting measurement information signals and the block diagram of a system for testing the inner diameter of pipes that allows testing under conditions of significant radial displacements of the eddy current probe inside the pipe. The effectiveness of the proposed engineering solutions is evaluated.

Annular combustors are traditional, while hollow combustors without centerbodies are becoming popular for rotating detonation engines. Both schemes are studied experimentally in this paper to determine which combustor demonstrates a better detonation performance and pressure gain performance. The hydrogen and air sources are at room temperatures of 280–285 K. The annular and hollow combustors have the same scheme, although the centerbody is removed from the hollow combustor. The combustors are made optically accessible by embedding a piece of quartz glass in the outerbody. The hollow combustor channel has an outer diameter of 100 mm, and the detonation channel of the annular combustor has an inner diameter of 60 mm. Fuel and air are injected into the combustor from 150 cylindrical orifices with a diameter of 0.8 mm and a circular channel with a throat width of 1 mm, respectively. The results show that the hollow combustor demonstrates a better detonation performance and a higher pressure gain than the annular combustor. High-speed images show the rotating detonation is propagating with a lap time which is in good agreement with that obtained from pressure traces.

The wax deposition of crude oil during transportation reduces the inner diameter, blocks the pipeline, and eventually increases the cost of petroleum production. This study reports a paraffin-degra...

Cerebral or intracranial aneurysm is a leading cause of subarachnoid hemorrhage. It was initially treated with open surgical clipping but as rapid development of technology a less invasive endovascular coiling technique of aneurysm revolutionized the treatment. Due to tortuous anatomy of parent artery and complicated morphology and location of aneurysm there is ongoing challenge in the complete obliteration of aneurysms. To aid in the advances of treating aneurysm stent assisted endovascular coiling was introduced to give more scaffold support to parent artery and decrease events of coil protrusion from aneurysms. Many types and generation of stents were developed. One of the most recently introduced stent is low profile visualized intraluminal support (LVIS) stent. Due to its low profile nature it can be used in 0.017-inch inner diameter microcatheter and reach small and complex vessels providing high aneurysmal neck coverage which was not possible through other traditional stent. In addition, its braided design with tantalum strands and radiopaque markers make it more visible during stent placement and post procedure stent evaluation. Despite of many advantages of LVIS stent it is related to high rate of thromboembolic complications and technical complications. Aim of this review paper was to evaluate therapeutic safety, effectiveness and feasibility of LVIS stent in endovascular coil embolization of intracranial aneurysms.

Digital PCR is a powerful amplification method for absolute quantification of nucleic acids. The systems that integrated the nucleic acid extraction and amplification can reduce detection time, improve accuracy, and reduce labor costs. However, current nucleic acid extraction systems cannot be integrated well with integrated fluidic circuit (IFC) dPCR or droplet digital PCR chips perfectly and limit the application of digital PCR. In this study, a polytetrafluoroethylene (PTFE)-based nucleic acid extraction (PNE) system, which was able to achieve fully closed extraction for micro samples and was able to be integrated with IFC dPCR or droplet digital dPCR (ddPCR) chips perfectly is proposed. For this system, PTFE tubing with an inner diameter of 1 mm was used to load the reagents and superparamagnetic particles (PMPs) were used to extract nucleic acids. The system can extract nucleic acids from cells and blood in 5 minutes. Meanwhile, when nucleic acid extraction was completed, PNE was able to be directly combined with IFC dPCR or ddPCR chips without any intermediate steps. Therefore, the PNE system can realize sample-in-digital-answer-out. It will be highly useful in point-of-care (POC) and promote the development and application of dPCR.

A miniature three-axis induction magnetometer (IM) for borehole logging was designed, manufactured, and tested. The form of the IM is a cube with 12 coils at edges, which are embedded in a ring cylinder. Thus, the 12 coils are placed along the x , y , and z axes. Each axis consists of four coils that are connected in series. The length, inner diameter, and outer diameter of the ring cylinder are 40, 43, and 64 mm, respectively. The mass of the IM is 450 g. The working frequency bandwidth is set within 1 Hz–10 kHz. The equivalent induction magnetic noise level of the IM is less than 10 pT/√Hz at 100 Hz for three axes. The features and the noise performances of the IM show the potential for its use in borehole logging.

The optical performance of two dimensional (2D) metallic nanoring arrays is inevitably affected by their substrate. This problem can be solved by using three dimensional (3D) nanorings, whose height is larger. However, most reported 3D-metallic nanoring arrays were prepared through focused ion beam lithography, which is high cost and low efficiency. Herein, we provided a new approach to fabricate highly ordered 3D-silver nanoring arrays (3D-AgNRAs) over a large area through multistep colloidal lithography combined with metal deposition. The specific structure of the 3D-AgNRAs could be facilely tuned by modulating the etching conditions. After gradual optimization of the 3D-AgNRAs’ structural parameters with respect to their optical and sensing performance, the optimized 3D-AgNRAs’ structural features were finally settled to be 1 μm period, 200 nm nanoring height, 300 nm silver layer thickness, 830 nm outer diameter, and 428 nm inner diameter. The optimized 3D-AgNRAs achieved high refractometric sensitivity of 1105.8 nm per RIU and relative sensitivity of 50.2% per RIU. Ultimately, the optimized 3D-AgNRAs were employed as an immunoassay substrate to prove their label-free biosensing potential in the future.

The aim was to evaluate the distribution of the diameter of the great saphenous vein (GSV) at mid-thigh level and to investigate its association with clinical class, symptoms, and proximal extent of reflux.Vascular physicians, members of the French Society of Phlebology, were invited to participate in a consecutive observational study in patients presenting with symptoms and/or signs of uni- or bilateral chronic venous disorders (CVDs) in previously untreated limbs (clinical class of the CEAP classification C0s - C6). Patients were included between January and March 2015. They completed a specially designed venous symptoms questionnaire. Duplex ultrasound of the included limbs was performed with the patient standing to detect reflux in the GSV and to measure the GSV inner diameter at mid-thigh.Between January and March 2015, 35 physicians examined 1245 patients (2450 limbs after excluding 40 limbs): 77% were female, mean age 52 ± 14; 69% of the patients had venous symptoms in one or both legs. The most frequent symptoms were feeling of heaviness, feeling of swelling and aching. Predominant CEAP clinical classes were C2 (38% of limbs) and C1 (35%). In case of GSV reflux (40% of limbs), the average diameter was 5.6 ± 2 mm and the distribution was 62% 6 mm, 30% between 6 and 8 mm, and 8% 8 mm. The study showed a clear association between clinical class and GSV diameter (the higher the clinical class, the larger the diameter; p .0001), between venous symptoms and diameter (the larger the diameter, the higher the intensity of symptoms, p .0001 for overall discomfort) and between proximal extent of reflux and diameter (the more proximal the extent of reflux, the larger the diameter, p .0001).The DIAGRAVES study demonstrated that in France for patients consulting with CVDs, more than half of the incompetent GSVs had a diameter 6 mm, while large diameters were relatively infrequent. This should be kept in mind when considering management strategies in patients with CVDs.

Objective. We aimed at assessing feasibility and safety of coronary angiography (CAG) and percutaneous coronary intervention (PCI) performed via distal radial access. Material and methods. Two-stage study was designed. First, radial artery diameter was measured with duplex ultrasound at the conventional (proximal) access and anatomic snuffbox (distal access) in 160 patients, and diameter percentage change was calculated. The given minimal difference in radial artery diameter at two access points CAG or PCI via distal access was performed in 134 patients to address safety outcomes at the study stage 2. Results. Median inner diameter of the radial artery was 2.3 (2.0-2.6) mm at the conventional access point, and 2.05 (1.8-2.5) mm – at the distal one. No access-related adverse events were recorded within intervention or during follow-up. Conclusions. The use of distal radial access to perform CAG and PCI is anatomically feasible and safe.