Injection Analysis Research Articles

Absorptiometric Determination of Chromium (VI) by Gradient Sandwich Injection/Sequential Injection Analysis

Absorptiometric Determination of Chromium (VI) by Gradient Sandwich Injection/Sequential Injection Analysis

Effects of the injection molding processing settings on the phase morphology and mechanical anisotropy of thermoplastic vulcanizates

AbstractThermoplastic vulcanizates show significant anisotropic mechanical properties when processed to components via injection molding. This effect is related to a process‐dependent distortion of the incorporated elastomer particles in high‐shear regions during the injection phase. In a plate geometry, the elastomer particles in the shear regions are oriented and deformed in the flow direction. However, the ongoing distortion processes and the influencing factors of the process parameters on the resulting phase morphology and mechanical response are not entirely understood. Therefore, in this study, the effect of the injection molding machine settings for the production of a plate component on the local phase morphology and mechanical anisotropy is investigated. The investigations are conducted on two commercial material grades with different Shore‐A hardness 30 and 90. A significant inverse effect of the injection volume flow rate on the particle distortion and anisotropy is found. Increasing the volume flow rate results in a reduction of the anisotropy. This is counterintuitive from the experience of other materials with process‐dependent anisotropy. Also, a significant influence of the process on the overall stiffness of the compounds is observed.Highlights Sturcture–property relation for phase morphology in thermoplastic vulcanizates Quantitative microstructure analysis in injection molded plates Macroscopic analysis of anisotropic mechanical response under uniaxial loading Effect analysis of injection molding parameters on the mechanical anisotropy Additional effects of process settings on overall stiffness of the material

Integrated analysis approach of water and solids for root cause of injectivity decline of water injection well – A case study

Accurate sampling and analysis of injection and flow back water and solids are pivotal to identify the root causes of injectivity decline of water injection well. The present paper is focussed on case study of detailed characterization of injection and flowback water and solids using combination of techniques such as X-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy, inductively coupled plasma optical emission spectroscopy, ion chromatography and water isotope analyser in investigating the cause of injectivity decline. The present study emphasizes the effect of pressurized and non-pressurized water sampling on water analysis results, their scaling tendencies and correlation with compositions of solids encountered. Surface pressurized injection water sample pH result was found acidic with a higher dissolved iron and lower total suspended solids (TSS). Non-pressurized water samples showed comparatively higher pH due to release of CO2. Langelier saturation index (LSI) and ScaleSoftPitzer™ program SI of pressurized water sample showed lower scaling tendency than the non-pressurized water sample. Non-pressurized water samples contained significantly higher concentrations of TSS than the pressurized water sample indicated precipitation of salts in non-pressurized sample. Composition of TSS revealed presence of iron-based compounds, calcite and gypsum. Geochemical and water isotope analysis showed identical composition of injection and flowback water. XRD and XRF analysis of trapped solids revealed different forms of iron oxides and iron sulphides as major phase along with appreciable amount of calcite and quartz. XRF analysis also showed traces of Cr, Mo, and Ni in trapped solids indicated corrosion of tubing/pipes. Solid composition correlates with scaling tendency predicted by ScaleSoftPitzer™ program SI. Presence of iron in pressurized injection water and iron compounds in solids indicate iron-based scale/corrosion as key reason for reduction in injectivity of the well. Systematic sampling, accurate and integrated analysis of water and solids can help to find the dominant causes of injectivity decline and direct oilfield engineers at well site to take appropriate remedial and preventive action.

Reply.

We appreciate the letter from Dr Raevis and would like to thank him for his response to our recent work.1Lee D.J. Scruggs B.A. Sánchez E. et al.Transient vision loss associated with pre-filled aflibercept syringes: a case series and analysis of injection force.Ophthalmol Sci. 2022; 2: 100115Abstract Full Text Full Text PDF PubMed Google Scholar Here we highlight valid points and provide certain clarifications. We agree with Dr Raevis’ comments regarding other factors related to syringe design that may have contributed to the episodes of severe transient vision loss seen in our case series. In our article, we discussed that factors such as siliconization and fluid viscosity may contribute to variability in injection force. Dr Raevis insightfully hypothesized that plunger shape and deformability may also play a role. The increased injection force generated from aflibercept prefilled syringes (PFS) may lead to increased plunger deformability, which may potentially allow additional volume to be expressed at the end of an injection by minimizing syringe dead space. Our team recently conducted a survey of ophthalmologists who regularly use aflibercept PFS,2Lee D.J. Scruggs B.A. Faridi A. et al.Survey of intravitreal injection outcomes amongst ophthalmologists using pre-filled aflibercept syringes [letter].Clin Exp Ophthalmol. 2022; 50: 803-805Crossref PubMed Scopus (0) Google Scholar and many respondents believed that syringe design plays a contributing factor to the spikes in intraocular pressure observed after aflibercept PFS use. Many of these physicians also reported that they have little tactile feedback when pushing down on the PFS plunger or when the plunger comes to a soft stop. This further corroborates Dr Raevis’ point. It would be interesting to study this theory in the future and to quantify the volume delivered beyond the target of 0.05 ml when applying this increased force at the end of an injection. We want to clarify that our study demonstrated that injection force was proportional to injection speed in all syringe types. Additionally, we showed that the aflibercept PFS required more force compared with other syringe types across all predetermined injection speeds while keeping the volume constant as measured by a lens optical system. The barrel inner diameter of the aflibercept PFS was 35% wider than that of the ranibizumab PFS. This finding explains the increased force generated and may also explain why more volume is delivered per second with the aflibercept PFS despite both syringe types having hollow tapered plunger tips. Overall, our original study findings and Dr Raevis’ additional insights into the matter highlight that plunger misalignment owing to user error may not sufficiently explain our clinical outcomes, and modifications to syringe design may be warranted. Taken together, our team suggests that syringe manufacturers improve syringe components so that physicians can (1) avoid misalignment of the plunger, (2) decrease the injection speed, and (3) avoid deformation of the stopper. Additionally, standardizing injection force across syringe designs by manufacturers may be useful in the future. Re: Lee et al.: Transient vision loss associated with prefilled aflibercept syringes (Ophthalmol Sci. 2022;2:100115)Ophthalmology ScienceVol. 2Issue 4PreviewLee et al1 evaluated multiple cases of severe transient vision loss after receiving an intravitreal injection of aflibercept from a prefilled syringe (PFS). They demonstrated that injection speed and syringe design both influence the injection force required to depress the syringe. Their data show that injection speed is directly proportional to injection force and recommend that physicians perform intravitreal injections at a slower rate. Full-Text PDF Open Access

Temperature perturbation and induced pressure under convective-conductive heat flow during wellbore CO2/CH4 injection/production

Thermal-hydraulic-mechanical (THM) responses of wellbores and those inside porous formations are of significant interest for injection design and forecast in energy extraction and production processes. In this study, a THM formulation incorporating conductive-convective heat transfer mechanism was developed. Closed-form solutions for temperature and pressure perturbations are developed incorporating the THM-induced effects near a cylindrical wellbore are analyzed. Solutions for both high-permeability and low-permeability formations were presented, simulating two separate processes, a convective-conductive and a conductive heat transfers, respectively. A Laplace transform technique was used and the inversely transformed solution was solved numerically. Solutions subject to type I-III boundary conditions are solved and analyzed, corresponding to different engineering processes in various rock formations. CO2/CH4 injection for sequestration and storage purposes were used as an example. The storage capacity and injectivity analysis are conducted with the acquired spatial and temporal changes in temperature and pore pressure inside the poroelastic medium and at the wellbor. Once the supercritical conditions are surpassed, the impacts of phase and thermal-hydraulic (TH) characteristics changes due to injected gas on injectivity, capacity, post-production safety, and operating design were highlighted.

Reinforced Composite as a Feeder for 3D Printing Application

Kenaf fibre has a low environmental impact because it is recyclable, light density and strong to be used as a product. Natural fibres, especially kenaf fibre, are undertilised and understudied in 3D printing technology. 3D technology is gaining traction to replace traditional methods because it saves cost and production time. This study focuses on producing kenaf composite materials that can be used as a feeder for 3D printing. This study used different fibre compositions (20,25,30) % mixed with polypropylene set at 190 ˚C temperature, 45 rpm speed, and 25 minutes. The material was left to cool to form clot to go through for the rheology process, and injection analysis was performed using Autodesk Moldflow Insight 2014. This study showed that a mixing temperature of 190 ˚C was suitable for forming a high shear mechanism. Kenaf fibre was treated in an alkaline solution of NaOH to 3 hours to prevent damage to the surface of the filler fibre in composites. Kenaf fibre at 6% of NaOH solution reaches a higher value for mechanical strength and roughness, resulting in better mechanical interlocking between the fibres and the matrix. In addition, analysis from Autodesk Moldflow Insight 2014 reveals that at 200 ˚C injection temperature pretend, the shear rate is higher creating smoother melt flow characteristics.

Injection over-molding warpage prediction of continuous fiber-reinforced thermoplastic composites considering yarn reorientation

The injection over-molding process combines thermo-stamping of continuous fiber reinforced thermoplastic (CFRTP) laminates and injection of plastic onto the surface of the CFRTP insert. A challenge for this process is to predict the warpage due to the influence of CFRTP insert. This work proposed a simulation method for predicting the warpage considering yarn reorientation induced in the thermo-stamping. In detail, the geometry and yarns reorientation of the deformed CFRTP inserts in thermo-stamping were calculated by a hybrid lamination model. Then the local thermo-mechanical properties were calculated according to the directions of reorientated yarns. Finally, the geometric and material information of CFRTP insert were imported into injection analysis, especially warpage prediction. The simulation method was validated by experiments on centrally injected bilayer plate and stiffened square box. This work highlights the importance of anisotropy induced from thermo-stamping on the final warpage of injection over-molded composite parts.

Evaluation of formulation-associated ifosfamide neurotoxicity.

e23562 Background: Ifosfamide, an alkylating agent used commonly in both hematologic and solid tumor malignancies, carries a notable risk for neurotoxicity/encephalopathy. Ifosfamide is available as both a reconstituted powder formulation and a solution for injection. Literature has shown that there may be higher rates of ifosfamide neurotoxicity/encephalopathy (INT/E) with the solution compared to the reconstituted powder. The primary objective of this study was to compare the rates of neurotoxicity/encephalopathy in association with the two available pharmaceutical formulations of ifosfamide. Methods: We performed a retrospective study of adult patients receiving at least one dose of either available pharmaceutical formulation of ifosfamide. The primary outcome was the incidence of formulation-associated INT/E. Secondary outcomes included additional risk factors for development of INT/E. Results: Of 218 patients evaluated, 212 were included in the study with 56 patients receiving the reconstituted powder formulation and 156 patients receiving the solution for injection formulation of ifosfamide. Baseline characteristics were similar between the two groups, including dose of ifosfamide received, use of INT/E prophylaxis, and renal and hepatic function. INT/E occurred in 4 patients (7.1%) receiving the reconstituted powder formulation vs 32 patients (20.5%) receiving the solution for injection (p = 0.022) Evaluation and analysis of additional risk factors for development of INT/E are ongoing, including the impact of baseline demographics, ifosfamide dosing, renal and hepatic function, and concomitant medications. Conclusions: In this study, hematology/oncology patients who were treated with ifosfamide had significantly lower rates of INT/E with the reconstituted powder formulation compared to the solution for injection. Further analysis regarding additional risk factors for INT/E development is ongoing.[Table: see text]

Analysis of wastewater injection and prospect regions for induced seismicity in the Texas panhandle, United States

Analysis of wastewater injection and prospect regions for induced seismicity in the Texas panhandle, United States

Quantitation of Butyrylcarnitine, Isobutyrylcarnitine, and Glutarylcarnitine in Urine Using Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS).

Acylcarnitines are formed when an acyl group is transferred from coenzyme A to a molecule of L-carnitine. In organic acidemias, and in fatty acid oxidation disorders, specific acylcarnitine species accumulate in a pattern that is characteristic for each disease. For this reason, acylcarnitine analysis is widely used for screening and diagnosis of inherited disorders of metabolism. The most common method for acylcarnitine analysis uses flow injection tandem mass spectrometry.Flow injection analysis allows for high throughput, however, does not provide separation of isomeric and isobaric compounds. Among the acylcarnitine species which can be affected by the presence of isomeric/isobaric compounds, C4-carnitine and C5DC-carnitine are probably the ones encountered most often. The method presented here is performed on urine and utilizes butanolic HCL to derivatize acylcarnitines, ultra-performance liquid chromatography to resolve C4- and C5-DC isomers and isobars, and quantitation of these species using multiple-reaction monitoring (MRM).

Analysis of intramuscular injections administered in a family health center

Analysis of intramuscular injections administered in a family health center

Predictive maintenance for system level analysis and diagnostics in injection molding machine

Predictive maintenance for system level analysis and diagnostics in injection molding machine

Tight Sandstone Reservoir Formation Mechanism of Upper Paleozoic Buried Hills in the Huanghua Depression, Bohai Bay Basin, Eastern China

Carboniferous-Permian petroleum resources in the Huanghua Depression of the Bohai Bay Basin, a super petroleum basin, are important exploration successor targets. The reservoir sedimentary environment of coal measures in the Upper Paleozoic buried hills is variable, and the structural evolution process is complicated, which restricts the optimization of targeting sections. Using the analysis and testing results of logging, thin section, porosity, mercury injection, hydrochemistry, and basin simulation, this study revealed the formation mechanism differences of tight sandstones in the Upper Paleozoic period in different buried hills. The results show that the sandstones are mainly feldspathic sandstone, lithic arkose, feldspathic lithic sandstone, and feldspathic lithic quartz sandstone. The quartz content varies between 25% and 70%, averaging 41%. Feldspar and debris are generally high, averaging 31% and 28%, respectively. Secondary dissolution pores are the main reservoir spaces, with 45% of the tested samples showing porosity of 5–10%, and 15% being lower than 5%. The pore radium is generally lower than 100 nm, and the sandstones are determined as small pore with fine throat and medium pore with fine throat sandstones by mercury saturation results. Frequent changing sedimentary environments and complex diagenetic transformation processes both contribute to the reservoir property differences. The former determines the original pore space, and the latter determines whether they can be used as effective reservoirs by controlling the diagenetic sequences. Combining tectonic movement background and different fluid history, the different formation mechanisms of high-porosity reservoirs are recognized, which are atmospheric leaching dominated (Koucun buried hills), atmospheric water and organic acid co-controlled (Wangguantun and Wumaying buried hills), and organic acid dominated (Nandagang buried hills) influences. The results can be beneficial for tight gas exploration and development in coal measures inside clastic buried hills in the Bohai Bay Basin.

HOTCAP: a new software package for high-speed oscilloscope-based three-dimensional bunch charge and position measurement

A software package to be used in high-speed oscilloscope-based three-dimensional bunch-by-bunch charge and position measurement is presented. The software package takes the pick-up electrode signal waveform recorded by the high-speed oscilloscope as input, and it calculates and outputs the bunch-by-bunch charge and position. In addition to enabling a three-dimensional observation of the motion of each passing bunch on all beam position monitor pick-up electrodes, it offers many additional features such as injection analysis, bunch response function reconstruction, and turn-by-turn beam analysis. The software package has an easy-to-understand graphical user interface and convenient interactive operation, which has been verified on the Windows 10 system.

Comprehensive Classification of Low and Ultra-Low Permeability Sandstone Reservoirs in Jidong Oilfield, China

Reservoir classification is an important content of reservoir evaluation, and has significance for the optimization of favorable areas and the formulation of development plans. Aiming at the characteristics of low and ultra-low permeability sandstone reservoirs in Jidong Oilfield, this paper selects sedimentary facies, sand body width, mean effective radius and effective percolation coefficient as evaluation parameters. Through conducting the macro qualitative analysis and microscopic quantitative evaluation, the classification boundary is determined by cluster analysis, a comprehensive evaluation system of low and ultra-low permeability sandstone reservoirs is established. The reservoirs are divided into four types, the physical properties get worse in turn of type I to III, and type IV is small sand body. The sedimentary facies of type I to III reservoirs are mainly bar host and fluvial channels, the inner edge of the bar, the outer edge of the bar and shoal in turn. The sand body width of type I to III is more than 300 m,and it is less than 300 m of type IV reservoirs. Based on the classification results, the feasibility analysis of water injection was carried out, and corresponding development policy recommendations are put forward for four types of reservoirs.

Spectrophotometric Methodologies Applied for Determination of Pharmaceuticals

Background: The development of innovative approaches in drug analysis is a challenging task for medicine, pharmacy, and engineering sciences. For instance, the requirement of proper dosage forms in releasing active ingredients is crucial. It is essential to analyze drugs in biological liquids for early diagnosis and treatment purposes. Drug analysis is also of great importance to control the quality of pharmaceutical products, test their efficacy, and develop novel drug formulation. The present review is aimed to highlight the most recent spectrophotometric approaches applied to analyze various classes of drugs in biological media and/or dosage forms. Methods: Direct and derivative UV/UV-Vis spectrophotometry and a combination of various techniques with spectrophotometry, such as injection analysis and chemometrics, have most widely been applied in the analysis of dosage forms. In addition, emerging technologies, such as UV imaging allows to obtain the distribution of drug concentration in time-resolved 2D images based on UV light absorption, utilization of nanotechnology, self-assembled nanomaterials, and aptamer-based nanoparticles have gained interests to investigate drug assays and to quantify the proper drug release. Results: Due to their high versatility, ease of application, low cost, and fast response, spectrophotometric methods are one of the most preferable methods providing high accuracy and precision with a wide linear range in drug analysis. Conclusion: Selected examples demonstrating the applicability of spectrophotometric methods in pharmaceutical assays in this review might contribute to the overall importance of the analytical test used in modern pharmaceutical analysis.

Real-time locally injective volumetric deformation

We present a highly efficient method for interactive volumetric meshless shape deformation. Our method operates within a low dimensional sub-space of shape-aware C ∞ harmonic maps, and is the first method that is guaranteed to produce a smooth locally injective deformation in 3D. Unlike mesh-based methods in which local injectivity is enforced on tetrahedral elements, our method enforces injectivity on a sparse set of domain samples. The main difficulty is then to certify the map as locally injective throughout the entire domain. This is done by utilizing the Lipschitz continuity property of the harmonic basis functions. We show a surprising relation between the Lipschitz constant of the smallest singular value of the map Jacobian and the norm of the Hessian. We further carefully derive a Lipschitz constant for the Hessian, and develop a sufficient condition for the injectivity certification. This is done by utilizing the special structure of the harmonic basis functions combined with a novel regularization term that pushes the Lipschitz constants further down. As a result, the injectivity analysis can be performed on a relatively sparse set of samples. Combined with a parallel GPU-based implementation, our method can produce superior deformations with unique quality guarantees at real-time rates which were possible only in 2D so far.

CFD Investigation of Rotational Sloshing Waves in a Top-Submerged-Lance Metal Bath

Computational fluid dynamics (CFD) is applied to investigate rotational sloshing waves in a top-submerged-lance (TSL) cylindrical metal bath. The study is an extension of a recent work of the authors, where the top injection of Ar into a metallic bath was examined in a quasi-2D flat setup, allowing the numerical model to be extensively validated against experimental data based on x-ray radiography. The new analysis of top gas injection in a cylindrical vessel reveals the appearance of rotational sloshing in the bath, which is maintained by a condition of synchronism between the gas bubbles and the free surface of the bath. A numerical quantification is achieved with specific post-processing of the simulation results, showing the effect of control parameters such as the lance immersion depth and the gas flow rate. This fundamental research study demonstrates the capability of CFD modeling to predict bath dynamics known from literature and practice, the understanding of which is essential for the design of TSL furnaces.

The Structural and Comparative Analysis of Intravitreal Dexamethasone Implant (Ozurdex) and Anti-VEGF Injection in Branched Retinal Vein Occlusion Patients by Optical Coherence Tomography Angiography Images Quantitation

ABSTRACT Background and Objective: To evaluate and compare the structural changes of retinal vasculature after intravitreal dexamethasone implant (Ozurdex) insertion and antivascular endothelial growth factor (anti-VEGF) injection in patients with branched retinal vein occlusion (BRVO) using optical coherence tomography angiography (OCTA). Study Design/Materials and Methods: We retrospectively analyzed 39 patients with unilateral BRVO. Subjects were divided into two groups according to treatment agent: Ozurdex (n = 18) and anti-VEGF (n = 21). Swept Source (SS) OCT and OCTA were performed and images were analyzed quantitatively using ImageJ (National Institutes of Health) software. Intravitreal implant and anti-VEGF injections were performed following a prn regimen. The specific anti-VEGF agent used was chosen among bevacizumab, ranibizumab and aflibercept. Results: Of the 39 patients (mean ± SD age, 70.0 ± 8.9 years [range, 48–89 years]; 20 men [51.0%]) with unilateral BRVO, in an independent two-sample t test, there was greater vascular reperfusion of the choriocapillaris slab in the intravitreal Ozurdex implant group than in the anti-VEGF group using the angiography mode (P = .013). Increased number of particles was more prominent in intravitreal anti-VEGF injection group than intravitreal Ozurdex implant group in outer retina slab of En-face mode (P = .039). There was no statistically significant difference between the 2 treatment groups in relation to the Early Treatment Diabetic Retinopathy Study (ETDRS) density map and other angiography slabs; and the superficial, deep, and outer retina. Conclusions: Results of a quantitative analysis of OCTA images using ImageJ software suggest that the intravitreal Ozurdex implant induced increased retinal vascular perfusion compared with anti-VEGF injection for the treatment of BRVO.

Numerical modeling of two-phase flow in deformable porous media: application to CO$$_2$$ injection analysis in the Otway Basin, Australia

Numerical modeling of two-phase flow in deformable porous media: application to CO$$_2$$ injection analysis in the Otway Basin, Australia