Leak Test Research Articles

PROSES PEMBUATAN TABUNG GAS 12 KG MENGGUNAKAN MATERIAL JIS-SG 255

A gas cylinder is a container in the shape of a tube and is used to store gas produced from oil refineries. The manufacturing process goes through various processes and the selection of strong materials to withstand the gas pressure in the cylinder. The main materials used in making the 12 kg gas cylinder are JIS SG 255 and SPHC. The 12 kg tube was designed with a tube height of 750 mm and a diameter of 280 mm. The SMAW welding process was carried out for the circumference and GMAW welding for the handguard and footring. To determine the area and volume of the weld on the 12 kg gas cylinder, area and volume calculations were carried out, so that it can be seen that the surface area of the 12 kg gas cylinder is 30.772 mm2, while the weld volume of the tube is known to be 115.395 cm3. Then, after welding the gas cylinder, proceed with annealing to restore the condition of the tube after welding with gradual heat temperatures, namely 200°C, 600°C and 200°C with a time of ± 14 minutes. Leak testing on tubes is carried out with two types of tests, namely hydrostatic tests and leak tests, hydrostatic tests on tubes use 31 bar water pressure with a quality of 50%, while for this leak test the tube is given air to find out whether the gas cylinder has a leak or not with a quality of 100 %.

Saline volume required to achieve peristaltic intraluminal pressure during leak testing of canine colotomies, using two methods of luminal occlusion

Background: No studies have appeared in the literature evaluating the intraluminal volume of injected saline in the canine colon for performing leak tests in colotomy incisions. Aim: To determine the volume of the injected intraluminal saline necessary to achieve an intraluminal pressure of 17.3 cm H2O in 10 cm colonic segments containing a closed colotomy occluded with intestinal forceps or by digital pressure. Methods: Fresh colon was obtained from 8 canine cadavers and divided into 10cm segments. A 3cm antimesenteric colonic incision was performed at each intestinal segment which was closed using a 3-0 polydioxanone suture in a simple continuous pattern. Each colonic construct was occluded with Doyen intestinal forceps or by digital pressure and a leak test was performed by saline infusion. The saline volume needed to achieve a predetermined intraluminal pressure of 17.3 cm H2O, following occlusion was recorded. Results: The mean volume of injected saline with the Doyen intestinal forceps occlusion (20.4 ± 8.2 ml) was significantly larger than that of the digital occlusion technique (17.5 ± 6.8 ml) [ P=0.021]. Conclusion: For 10 cm canine colonic constructs containing a closed colotomy, saline volumes of 20.4 ml with Doyen occlusion and 17.5 ml with digital occlusion can be utilized to achieve intraluminal pressures of 17.3 cm H2O.

In vitro study on the sealing effect of different shapes of cuff tracheal tubes under the lowest safe pressure

To compare the effectiveness of cylindrical-shaped and conical-shaped cuff catheters for airway closure using different pressure measurement methods at the lowest safe pressure and to guide the clinical application. Twenty-four patients with endotracheal intubation admitted to the intensive care unit (ICU) of Guangxi Medical University Cancer Hospital from December 2021 to January 2022 were enrolled. Leakage test in vitro was performed on the secretion on the patients' cuff. The needle and plunger from 20 mL syringe was separated, the syringe was sealed with adhesive, and the syringe nozzle was filled thoroughly to create a tracheal model. Consecutively, both cylindrical-shaped and conical-shaped cuff catheters were inserted into the simulated trachea, and the cuff pressure was calibrated to 20 cmH2O (1 cmH2O ≈ 0.098 kPa) before commencing the experiment. The viscosity of the secretion on the patients' cuff was classified (grade I was watery subglottic secretion, grade II was thick subglottic secretion, grade III was gel-like subglottic secretion), and the same viscosity secretion was injected into the catheter cuff. Utilizing a self-control approach, intermittent pressure measurement was initially conducted on both the cylindrical-shaped and conical-shaped cuff by improved pressure measurement method (intermittent pressure measurement group), followed by continuous pressure measurement experiment (continuous pressure measurement group). The leakage volume of the three viscosity subglottic secretions and the values of cuff pressure measurement of different shaped cuff catheters at 4, 6, 8 hours of inflation were recorded. A total of 180 retention samples were extracted from 24 patients with tracheal intubation during ventilation, with 90 samples in each of the two groups using different pressure measurement methods, and 30 samples of retention materials with different viscosities in each group. In the intermittent pressure measurement group, at 4 hours of inflation, all samples of secretion with grade I and grade II on cylindrical-shaped cuff leaked, while 3 samples of secretion with grade III also leaked. For conical-shaped cuff, 28 samples of secretion with grade I leaked, only 2 samples of secretion with grade II leaked, and there was no leak for secretion with grade III. At 6 hours of inflation, all samples of the three viscosity secretions on different shaped cuffs leaked. The leakage was gradually increased with the prolongation of inflation time. In the continuous pressure measurement group, at 4 hours of inflation, all samples of secretion with grade I on cylindrical-shaped cuff leaked, while 29 samples of secretion with grade II leaked, and there was no leak for secretion with grade III. For the conical-shaped cuff, 26 samples of secretion with grade I leaked, and there was no leak for secretion with grade II and grade III. At 6 hours of inflation, the conical-shaped cuff still had no leak for secretion with grade III. As the inflation time prolonged, the leakage of subglottic secretion on different shaped cuffs in both groups was gradually increased. At 8 hours of inflation, all samples experienced leakage, but the leakage of subglottic secretion on different shaped cuffs in the continuous pressure measurement group was significantly reduced as compared with the intermittent pressure measurement group [leakage for secretion with grade III (mL): 1.00 (0.00, 1.25) vs. 2.00 (1.00, 2.00) on the cylindrical-shaped cuff, 1.00 (0.00, 1.00) vs. 2.00 (2.00, 2.00) on the conical-shaped cuff, both P < 0.01]. The values of pressure measurement of cuffs with different shapes at different time points of inflation in the continuous pressure measurement group were within the set range (20-21 cmH2O). The cuff pressure at 4 hours of inflation in the intermittent pressure measurement group was significantly lower than the initial value (cmH2O: 18.3±0.6 vs. 20.0±0.0 in the cylindrical-shaped cuff, 18.4±0.6 vs. 20.0±0.0 in the conical-shaped cuff, both P < 0.01), and the cuff pressure in both shaped cuffs showed a significant decrease tendency as inflation time prolonged. However, there was no statistically significant difference in values of pressure measurement between the different shaped cuff catheters. Continuous pressure monitoring devices can maintain the effective sealing of conical-shaped cuff catheters at the lowest safe pressure. When using an improved pressure measurement method for intermittent pressure measurement and/or using a cylindrical cuff catheter, the target pressure should be set at 25-30 cmH2O, and the cuff pressure should be adjusted regularly.

A Double Remote Magnetic Field Synthesis Method for Reducing High-Speed MFL Signal Distortion Caused by Velocity Effect

Magnetic flux leakage (MFL) testing is coming into prominence as an inspection tool applied to pipeline evaluation. The MFL detectors are challenging to accurately evaluate pipe defects at high-speed due to velocity effects. Current methods typically require detectors to operate at low speeds or compensate for detection data offline, but they reduce detection efficiency or require sophisticated algorithms. In this article, a novel double remote magnetic field synthesis (DRMFS) method is proposed to address the issue. First, we give a thorough analysis of the influence of velocity effects on high-speed MFL signals, reinterpreting its action mechanism. Secondly, the critical parameters are optimized to improve pipe magnetization. The relationships between the sensor layout and normalized signal similarity are studied at different speeds to reduce signal distortion. Finally, the usability of the DRMFS method in reducing signal distortion and its capability in detecting deep defects are validated by measuring defect depths. Results showed synthesis signals are highly similar to static MFL signals and approximately linear with the defect depth, which could improve the detection accuracy. Our results can enable the exploration of information utilization in limited space and the establishment of a balance between detection efficiency and signal accuracy.

Roll-to-roll manufacturing of large surface area PDMS devices, and application to a microfluidic artificial lung.

The ability to cost-effectively produce large surface area microfluidic devices would bring many small-scale technologies such as microfluidic artificial lungs (μALs) from the realm of research to clinical and commercial applications. However, efforts to scale up these devices, such as by stacking multiple flat μALs have been labor intensive and resulted in bulky devices. Here, we report an automated manufacturing system, and a series of cylindrical multi-layer lungs manufactured with the system and tested for fluidic fidelity and function. A roll-to-roll (R2R) system to engrave multiple-layer devices was assembled. Unlike typical applications of R2R, the rolling process is synchronized to achieve consistent radial positioning. This allows the fluidics in the final device to be accessed without being unwrapped. To demonstrate the capabilities of the R2R manufacturing system, this method was used to manufacture multi-layer μALs. Gas and blood are engraved in alternating layers and routed orthogonally to each other. The proximity of gas and blood separated by gas permeable PDMS permits CO2 and O2 exchange via diffusion. After manufacturing, they were evaluated using water for pressure drop and CO2 gas exchange. The best performing device was tested with fresh whole bovine blood for O2 exchange. Three μALs were successfully manufactured and passed leak testing. The top performing device had 15 alternating blood and gas layers. It oxygenated blood from 70% saturation to 95% saturation at a blood flow of 3 mL min-1 and blood side pressure drop of 234 mmHg. This new roll-to-roll manufacturing system is suitable for the automated construction of multi-layer microfluidic devices that are difficult to manufacture by conventional means. With some upgrades and improvements, this technology should allow for the automatic creation of large surface area microfluidic devices that can be employed for various applications including large-scale membrane gas exchange such as clinical-scale microfluidic artificial lungs.

LOW TEMPERATURE SEALING BEHAVIOR EVALUATION OF ELASTOMERS IN AIRCRAFT HYDRAULIC SYSTEMS

ABSTRACT The low temperature sealing behaviors of five elastomer components used in aircraft hydraulic sealing systems were evaluated through a series of tests subsequent to exposure at 135 °C for a maximum of 28 days in air or hydraulic oil. These assessments encompassed standard material tests such as glass transition temperature (Tg), temperature retraction at 10% shrinkage, mechanical test, and compression set and a customized test to measure sealing force of a certain temperature. In addition, a low temperature gas leakage test was conducted. NBR stiffened upon aging with degradation of properties in an elongation loss, and Tg increased because chain mobility decreased due to increased crosslink density, and restoring force sharply decreased in cooling and in extracting plasticizer. In contrast, in the gas leakage test for both fluorocarbon rubber (FKM) and blends of epichlorohydrin with NBR (ECO), the Tg values showed good accordance, with minimal sealing temperature (Tseal), whether FKM or ECO were aged or not. However, the value of Tseal is significantly higher than that of Tg after NBR aging, indicating a complicated sealing mechanism. Thus, relying solely on standard material tests may not suffice for accurately forecasting the low temperature sealing performance in aircraft hydraulic sealing systems.

Injection mold improvement for a jar for cosmetic use through CNC machining

This project shows the improvement of a three-gram capacity jar for cosmetic use, manufactured by the company Ingeniería, Pailería Industrial y Mantenimiento S.A. de C.V. (IPIMSA). The jar for cosmetic use showed a leak between the jar and the lid, by means of the leak test, in a vacuum machine. To determine the root cause, an Ishikawa diagram is used, later, it was analyzed that the 110 T horizontal injection machine (Van Dorn) is in perfect condition, the problem was identified when disassembling the plastic injection mold, since the plate for the string of the jar was machined with the concentricity offset by one millimeter, causing the walls of the string of the jar to be uneven and thin, which is why the objective of this project is to improve the machining of the string generating plate of the jar. Jar for cosmetic use, to meet the leak test by the customer. For the machining, the Haas VF2 CNC machining center with a resolution of 0.001 mm, from the Universidad Tecnológica del Valle de Toluca, was used.

N-oktadekan / biyokömür kompoziti: hazırlanması, karakterizasyonu ve enerji depolama özellikleri

Biochar (BC) is a carbonized material rich in functional groups that has many different uses such as soil reclamation, energy storage, anodic material in batteries and electromagnetic emission capture in buildings. The n-octadecane (OD) is a favourable organic phase change material (PCM) for thermal energy storage which can be applied in building energy storage materials due to its proper phase change temperature. In this study, BC was impregnated with the OD in the vacuum oven at 0.08 Mbar at 70 °C for 3h. The weight percentage gain was found to be 50% after impregnation. Leakage of OD from BC after impregnation was detected by leakage test. The physico-chemically characterize of thermally treated wood samples were examined by Fourier Transform Infrared Spectroscopy (FT-IR). Thermal degradation stability of the samples were analyzed by thermogravimetric analyses (TGA) and diffential scanning calorimetry (DSC) analysis. According to results, no leakage was observed after the leakage test in BC samples impregnated with OD. A significant amount of residue was evident in the BC after it was infused with OD indicating that its decomposition commenced only at markedly high temperatures according to TGA results. The FTIR spectrum doesn't show any extra absorbance peaks. According to obtained results, BC/OD exhibits favourable characteristics suitable for energy storage in buildings or similar applications.

Characterization of 1-tetradecanol’s performance as a phase change material in thermally modified ash wood

The use of phase change materials in thermally modified wood presents an innovative way to enhance the thermal properties of wood, contributing to energy efficiency and thermal comfort in various applications. However, careful consideration of the materials and methods used is essential to ensure the effectiveness and practicality of this technology. Phase change materials (PCM) can be integrated into thermally modified wood through various methods. One common method is impregnation, where the PCM is infused into the wood structure. Another method could be the application of PCM in coatings or finishes applied to the wood surface. In this study, 1-tetradecanol (TD) was used as a PCM and its effectiveness on thermally modified ash wood (TMA) was investigated. TMA has better thermal insulation properties, which are essential in energy storage applications to minimize heat loss. For this purpose, the leaching of TD from TMA was examined. Differential scanning calorimetry (DSC), thermogravimetric analyses (TGA), fourier transform infrared spectroscopy (FTIR) were examined. According to the results, there was a small amount of leakage in the leakage test. TGA analysis showed that TD/TMA left a lower residue of 16.30% at 800°C compared to the residue of 18.20% left by untreated thermally modified wood (TMA).

Biological Synthesis and Characterization of Silver-Doped Nanocomposites: Antibacterial and Mechanistic Studies

The development of antimicrobial resistance has increased the prevalence of infectious diseases, causing a global health problem that accounts for over 4.95 million deaths worldwide annually. The side effects associated with current antibiotics prompt a crucial need to search for effective and safe antimicrobial agents. In this study, silver nanoparticles (AgNPs) were prepared by chemical reduction method using silver nitrates as a metallic precursor and Croton macrostachyus bark aqueous extract as a reducing and capping agent. The nanoparticles were further functionalized using C. macrostachyus-based activated carbon (CAC) to generate nanocomposites (CAC-AgNPs). The nanomaterials were characterized by ultraviolet-visible (UV–vis) absorption spectra and Fourier transform infrared (FTIR) spectra. The antibacterial activity of the as-prepared nanomaterials was evaluated against an array of bacterial strains by microdilution method, whereas their cytotoxicity profile was evaluated using Vero cells (human mammalian cells). Antibacterial mechanistic studies of active nanomaterials were carried out through bacterial growth kinetics, nucleic acid leakage tests, and catalase inhibition assays. As a result, the as-prepared nanomaterials exhibited antibacterial activity against an array of bacterial strains (minimum inhibitory concentration (MIC) range: 62.5 to 500 µg/mL), the most susceptible being Escherichia coli and Staphylococcus aureus. Cytotoxicity studies of the nanomaterials on Vero cells revealed that the nanocomposite (median cytotoxic concentration (CC50): 213.6 µg/mL) was less toxic than its nanoparticle (CC50 value: 164.75 µg/mL) counterpart. Antibacterial mechanistic studies revealed that the nanomaterials induced (i) bacteriostatic activity vis à vis E. coli and S. aureus and (ii) inhibition of catalase in these bacteria. This novel contribution regarding the antibacterial mechanisms of action of silver nanocomposites from C. macrostachyus-based activated carbon may contribute to our understanding of the antibacterial action of these biomaterials. Nevertheless, more chemistry and in vivo experiments as well as in depth antibacterial mechanistic studies are warranted for the successful utilization of these antibacterial biomaterials.

A modular artificial intelligence and asset administration shell approach to streamline testing processes in manufacturing services

The increasing demand for personalized products and cost-effectiveness has highlighted the necessity of integrating intelligence into production systems. This integration is crucial for enabling intelligent control that can adapt to variations in features, parts, and conditions, thereby enhancing functionalities while reducing costs. This research emphasizes the incorporation of intelligence in testing processes within production systems. We introduce a novel approach for controlling testing functionality using an asset administration shell enriched with modular artificial intelligence. The proposed architecture is not only effective in controlling the execution behavior through services but also offers the distinct advantage of a modular design. This modularity significantly contributes to the system’s adaptability and scalability, allowing for more efficient and cost-effective solutions as different machine-learning models may be substituted to meet requirements. The effectiveness of this approach is validated through a practical use case of leak testing, demonstrating the benefits of the modular architecture in a real-world application.

Combining with domiphen bromide restores colistin efficacy against colistin-resistant Gram-negative bacteria in vitro and in vivo

Today, colistin is considered a last-resort antibiotic for treating multidrug-resistant (MDR) Gram-negative bacteria (GNB). However, the increased and improper use of colistin has led to the emergence of colistin-resistant (Col-R) GNB. Thus, it is urgent to develop new drugs and therapies in response to the ongoing emergence of colistin resistance. In this study, we investigated the antibacterial and antibiofilm activities of the quaternary ammonium compound domiphen bromide (DB) in combination with colistin against clinical Col-R GNB both in vitro and in vivo. Checkerboard assay and time-kill analysis demonstrated significant synergistic antibacterial effects of the colistin/DB combination. The synergistic antibiofilm activity was confirmed through crystal violet staining and scanning electron microscopy (SEM). Furthermore, the colistin/DB combination exhibited increased survival rates in infected larvae and reduced bacterial loads in a mouse thigh infection model. The cytotoxicity measurement and hemolysis test showed that the combination did not adversely affect cell viability at synergistic concentrations. The alkaline phosphatase (ALP) leak test and propidium iodide (PI) staining analysis further revealed that the colistin/DB combination enhanced the therapeutic effect of colistin by altering bacterial membrane permeability. The ROS assays revealed that the combination induced the accumulation of bacterial ROS, leading to bacterial death. In conclusion, our study is the first to identify DB as a colistin potentiator, effectively restoring the sensitivity of bacteria to colistin. It provides a promising alternative approach for combating Col-R GNB infections.

Comparing equations of state for their prediction of physical properties and pressure rise in confined water–MEG subsea systems

Lean MEG is a commonly used liquid in subsea facilities for hydrate inhibition, hydrostatic and leak testing, or holding in confined systems after subsea installation. However, the high thermal expansivity of MEG may lead to over-pressurisation in confined systems owing to small temperature increases in the surroundings, causing safety concerns. Accurate methods to predict thermally induced pressure rises, therefore, are essential for adequate sizing and operational management. This study assessed the performance of three equations of state (EoS) (Peng–Robinson PR78A, Cubic Plus Association (CPA-PR78A), and the high accuracy EoS CSMA). The physical properties considered in this study included density, isothermal compressibility and thermal expansivity of liquid water–MEG mixtures. The effect of the accuracy of these properties on prediction of thermally induced pressure rises in confined water–MEG subsea systems was then validated with field data. It was found that cubic and the cubic-related EoS significantly underpredict the liquid isothermal compressibility, leading to overprediction of the thermally induced pressure rise of liquid water–MEG mixtures in a confined subsea system. In contrast, the predictions of the liquid compressibility and the pressure rise by the high accuracy EoS CSMA are in good agreement with the measured field data. This confirms that the CSMA EoS is the better thermodynamic model for modelling pressure rise predictions for liquid water–MEG mixtures in confined subsea systems. Since salts are always present in subsea systems, their effect on the physical properties and simulated pressure rises were also investigated. It was found that the effect of salts on liquid density, compressibility and thermal expansivity may be correlated with salt concentration and treated as a perturbation to salt-free water–MEG mixtures. The effect of salts on the predicted pressure rise will provide valuable guidance to the industry.

Comparison between Bio-PET and PET for food container

The environmental issue of single-use plastic is extremely discussed due to waste accumulation and the consumption of non-renewable resources. This study aims to investigate the properties of bioplastic compared to petroleum-based plastic. Two stages of stretch blow molding were used to fabricate polyethylene terephthalate (PET) and bio-polyethylene terephthalate (Bio-PET) bottles. The shelf life extension of chili sauce paste stored in PET and Bio-PET containers with an oxygen scavenger at 45 ℃ in an accelerated condition was investigated. After twelve weeks, the chili sauce paste stored in the container bottle was observed. PET and Bio-PET bottles without oxygen scavengers were also determined as a control for comparison. The result showed that both PET and Bio-PET bottles with oxygen scavengers could prolong the quality of chili sauce paste similarly, meaning that PET could be replaced by Bio-PET as a chili sauce paste container. Other properties, such as thickness gauge, color, leak test, drop test, and close-open force of the container bottle, were also verified to check the product quality standard.

Standardized in vitro bleeding tests in a non-coated novel hybrid prosthesis for frozen elephant trunk demonstrates minimal oozing during full heparinization, supported by clinical data.

Recent reports have questioned the blood impermeability of the novel frozen elephant trunk (FET) device E-vita Open NEO© (EO-NEO). Therefore, standardized in vitro bleeding tests using porcine heparinized blood were performed, as well as stress testing on the blood tightness of the collar suture line, to investigate this observation. EO-NEO prostheses were examined in vitro for blood permeability in three test series. Initially, antegrade perfusion with heparinized porcine blood [activated clotting time (ACT) of 500 s, with a 60 min duration] was performed, followed by ante/retrograde testing via the EO-NEO side port. Testing of the collar suture line under a tension of 10 Newton (N) within a suspension device (blood pressure 120 mmHg, ACT of 560 s, 1 min duration) was carried out with the suture material force fiber white (FFWs) yarn, using standard fixation (5 stitches/cm), FFWh yarn in hemostatic fixation (15 stitches/cm), and flow weave yarn (FWYh). Blood permeability testing of EO-NEO through the prosthetic lumen or via the side port demonstrated minor leakage without statistical difference between the standard and hemostatic suture lines or suture materials used, or positioning on the crimped or tapered portion (p > 0.05). The specific collar anastomosis testing demonstrated leakage volumes of 140 ml/min for FFWs vs. 16 ml/min for FFWh (p = 0.02), vs. 9 ml/min with the FWYh (p = 0.01). Different blood leakage tests showed minimal oozing and no difference in blood loss through the fabric and different collar suture lines, but unphysiological pressurized retrograde perfusion of the collar region showed significantly less leakage using FWYh and FFWh, prompting production modification of EO-NEO. Clinical results confirmed low blood loss using this novel FET device.

Qualification of Compensatory Test Methods Involving Pressure Increase in the VVER Containment System

In general, containment leakage testing of nuclear power plants with VVER reactors by elevated pressures using the compensatory leakage detection method (CLDM) can be performed at pressures and pressure increase rates higher than those stipulated by the regulations using the absolute pressure method (AP method). Elevated pressures and pressure increase rates under certain conditions can violate safety limits of the containment systems and/or decrease the reliability/life of containment structures and equipment. These factors determine the need to qualify the CLDM to promote conditions for reliability and safety. A non-stationary thermodynamic model of the qualification conditions for CLDM testing of the containment was developed. The criteria for CLDM qualification conditions are the maximum allowable pressure and pressure increase rate during testing. The CLDM condition for recording leakage in the containment is pressure stabilization in the containment systems. Based on the developed CLDM thermodynamic model, it was established that the containment leakage rate is determined by the flow rate of air entering the containment systems and by the thermodynamic state of the air inside and outside the containment systems. The established qualification conditions were used to determine conditions for the minimum recorded leakage sizes within CLDM and the maximum allowable ambient air flow rates and test duration. A prerequisite for justifying the qualification and implementation of the CLDM is to revise/amend regulatory and technical requirements for the maximum allowable pressure and pressure change rate in the containment systems and for the conditions for disconnecting containment systems passive heat removal systems (if any) during testing.

Driver Safety High Cabin and Chassis Design in Diesel Forklifts

Purpose: In general, most forklift accidents occur due to rollover. After a rollover, the first affected part is the driver's cabin, followed by the chassis and parts. In the study, cabin and chassis designs of diesel forklifts with increased driver safety and performance were made.&#x0D; Methodology: Cabin and chassis tests were carried out with the Solid works program. According to the test results, the chassis and cabin design was made. Welding and assembly processes on the chassis of high-strength materials suitable for this design have been completed.&#x0D; Findings: As a result of the studies, the cabin design, which is different from other similar forklifts, notches on the edges of the fender, the removal of fuel and oil tanks from the chassis, eliminating the leakage test, and the steps on the sides of the chassis being made monolithic, are important innovations.&#x0D; Unique contributor to theory, policy and practice: As a result of all these studies, our KFD30 model was developed. This new model stands out with its new design and manufacturing on the forklift.

Effect of Alloying Additives and Moulding Technology on Microstructure, Tightness, and Mechanical Properties of CuSn10 Bronze.

Thise research was conducted to determine the impact of the applied casting technology, mould and alloying additives on the tightness of the CuSn10 cast alloy. Under industrial conditions, a series of experimental melts were made that were characterised by varying the concentrations of the main alloying element (Sn) and the introduced alloying additives (Si, Zn, Zr). The mould was made from green sand and used the CO2 moulding process. To assess the influence of the alloying additives, a metallographic analysis of the studied alloy was carried out, and the alloy's microstructure was examined using optical and scanning electron microscopy. The introduced alloying additives affected the properties and microstructure of the studied alloy. As alloying additives, zirconium resulted in a visible refinement of the microstructure, while silicon improved the fluidity and quality of the casting's external surface. The use of alloying additives and moulds made using different technologies is intended to improve the structure of the tin bronze castings produced and to find the best solution to significantly eliminate the lack of leakage of the castings. The castings were subjected to mechanical processing, and a leak test was performed using the pressure drop method. The conducted research allowed us to determine which technology, applied to production, will bring about a reduction in the problem and will inform further investigations.

Irreversible Bonding of Polydimethylsiloxane-Lithium Niobate using Oxygen Plasma Modification for Surface Acoustic Wave based Microfluidic Application: Theory and Experiment.

Acoustic microfluidic chips, fabricated by combining lithium niobate (LiNbO3) with polydimethylsiloxane (PDMS), practically find applications in biomedicine. However, high-strength direct bonding of LiNbO3 substrate with PDMS microchannel remains a challenge due to the large mismatching of thermal expansion coefficient at the interface and the lack of bonding theory. This paper elaborately reveals the bonding mechanisms of PDMS and LiNbO3, demonstrating an irreversible bonding method for PDMS-LiNbO3 heterostructures using oxygen plasma modification. An in-situ monitoring strategy by using resonant devices is proposed for oxygen plasma, including quartz crystal microbalance (QCM) covered with PDMS and surface acoustic wave (SAW) fabricated by LiNbO3. When oxygen plasma exposure occurs, surfaces are cleaned, oxygen ions are implanted, and hydroxyl groups (-OH) are formed. Upon interfaces bonding, the interface will form niobium-oxygen-silicon covalent bonds to realize an irreversible connection. A champion bonding strength is obtained of 1.1 MPa, and the PDMS-LiNbO3 acoustic microfluidic chip excels in leakage tests, withstanding pressures exceeding 60 psi, outperforming many previously reported devices. This work addresses the gap in PDMS-LiNbO3 bonding theory and advances its practical application in the acoustic microfluidic field.

Pelaksanaan Quality Control Pesawat Sinar X di Pelayanan Radiodiagnostik

Background: Quality Control can be used as a monitoring of the reliability of X-Ray Unit during the validity period of the Conformity Test Certificate. During the use of X-ray Unit, there is the potential for damage to components during the validity period of the certificate of passing the Compliance Test. If the X-Ray Unit Reliability Test is only carried out during the Compliance Test, then if there is a decrease in the quality and safety of the X-ray Unit it cannot be immediately known. This has the potential to endanger patients, radiation workers and the public. In Banyumas Regency, there are 80 Radiation Source Utilization Permits spread across 34 radiodiagnostic installation. Preliminary studies show that not all radiodiagnostic installation carry out routine X-ray machine reliability tests according to the Keputusan Menteri Kesehatan Republik Indonesia Nomor 1250/Menkes/SK/XII/2009 Tentang Pedoman Kendali Mutu (Quality Control) Peralatan Radiodiagnostik.&#x0D; Method: This research type is qualitative with survey of 20 radiodiagnostic installation using a questionnaire instrument. Quality control conducted periodically includes kVp accuracy test, linearity and reproducibility mA, exposure time accuracy test, tube leak test, collimator beam suitability test, collimator shutter efficiency test, collimator light strength test, HVL measurement, implementation of reject analysis program and availability and qualifications of quality control officers and availability of quality control equipment. Then the data will be grouped based on research objectives and presented descriptively.&#x0D; Result: From the results of data collection, 1 hospital did not have a quality control officer and 4 hospitals had a quality control officer with an educational background of Diploma IV in Radiology Engineering without any Radiology Equipment Quality Control training. Meanwhile, 15 hospitals have quality control officers with an educational background in the Medical Physics Undergraduate Program and have attended training in Quality Control of Radiology Equipment. Of the 20 hospital radiology installations, there were 7 hospitals that did not carry out the Reject Analysis Program. This was done with the assumption that Digital Radiography had been used in both the CR and DR modalities. A number of 13 hospitals continued to carry out the Reject Analysis Program even though they had used Digital Radiography. Of the 20 hospital radiology installations, there are 6 hospitals that independently carry out X-ray unit testing within the framework of a quality control program. However, only 1 hospital conducts regular testing. Testing is also limited to the accuracy of the collimator field and the strong light of the collimator. Fourteen hospitals did not carry out a quality control program independently but only carried out an X-ray unit calibration test once a year which was carried out by BPFK and an X-ray unit distributor company.&#x0D; Conclusion: The implementation of quality control of x-ray machines on a regular basis has not been carried out by all radiodiagnostic services, even though they already have quality control officers. One of the reasons is the availability of quality control equipment needed for testing and supervision of radiodiagnostic service management. The role of management of radiodiagnostic services is needed to overcome these problems.&#x0D; &#x0D; Keyword : Quality Control Programe, Compliance Test, X-Ray Unit