Larger Internal Diameter Research Articles

Time-dependent force depreciation of intraoral orthodontic elastics of variable force and lumen sizes – An in vitro study

: To evaluate force decay of elastics of different dimensions and different force values over 48-hours.Steps included extension and immersion of elastics in artificial saliva and measurement of force levels at a specified point of time. A model with vertical pins placed at in the oral cavity. The initial force measurement was done using Universal testing machine before the elastics were engaged onto the pins 37⁰C in artificial saliva. The reading was taken after this in the Universal testing machine for the samples. The elastics were then placed back into the static simulation for the next 23 hours and again into the dynamic simulation for the next 1 hour. Statistically significant difference (P<0.05) was observed between force depreciation between rest and maximum stretch of the elastic. Statistically significant difference was observed in force depreciation with varying time intervals of a particular elastic sample. Lumen size and pre-determined force values affect the overall force decrease pattern of elastics. Elastics with higher force and smaller lumen size show comparatively higher loss of force than the lighter elastics with larger internal diameter. The maximum force loss of a particular elastic happens within the first 24 hours of elastic stretch. The study would help provide information about how an elastic's lumen size and initial force are interdependent, giving clinicians a better understanding of how to prescribe the right elastics for the force they need to apply for treatment.

Diagnostic system of the facility for studying superconducting quadrupoles

For the HED@FAIR project, NRC “Kurchatov Institute” — IHEP creates four quadrupole magnets with a unique combination of a large internal diameter of the superconducting winding and a high magnetic field gradient in the magnet aperture. To evaluate these superconducting magnets in different operation modes (cooling, maintaining operating parameters, heating, and transitioning magnet to the normal state), a cryogenic facility equipped with a diagnostic system was created. The main measured parameters of the unit were temperature, pressure, and vacuum in the equipment and pipelines, levels of liquid helium and liquid nitrogen, level of the gas holder, and helium flow rate. The control devices were represented by valves with electric and valves. For processing incoming signals from sensors and generation of control actions, the equipment of the domestic company OVEN was used, particularly analog input modules MV110, discrete output modules MU110, and interface converters alternating current four and direct current power supplies. The critical part of the diagnostics system, namely, the control of cryogenic valves, was provided through analog output modules NI 9219 and input modules NI 9212 (feedback) of the CompactRIO chassis. The program part of the installation for the study of superconducting quadruples is a mnemonic diagram with interactive graphic elements, physically located on the computer (operator console), and available in the read mode via the remote desktop protocol to users outside the installation. The mnemonic scheme allows the manual control of the plant’s valves and the automatic regulation of some indicators, depending on the settings assigned by the operator. The dynamics of the processes can be monitored with graphs on the right side of the interface. These graphs are displayed on a separate display at the operator’s console, whereas they are displayed on a unified screen for remote users.

Investigation of shot sleeve distortion and oil cooling in high pressure die casting

It is well known that thermomechanical distortion reduces the service life of shot sleeves in high pressure die casting (HPDC) processes. However, the underlying phenomenon which causes the distortion is still not well characterized. While finite element models (FEM) have been used to analyze shot sleeve distortion, these have typically used simplified 2D representations and do not consider the effect of transient molten metal flow on heat transfer. In the present study, a 3D finite element (FE) model based on ANSYS used a staggered approach to study the sources of shot sleeve distortion and the effect of active oil cooling. Transient flow behavior during pouring, settling, and slow shot phases was simulated using a computational fluid dynamics (CFD) based model after which the temperature field and internal pressure distribution were imported into a structural model which was used to predict shot sleeve distortion at selected instants during a representative steady-state cycle. The simulation results were validated using data obtained from an HPDC machine and demonstrated good agreement. A comparison of large and small internal diameter (ID) shot sleeves showed that the former distort the most and that cooling channels are only moderately effective at minimizing distortion. Based on the complex 3D nature of shot sleeve distortion, the use of total indicator runout (TIR) is also proposed as a metric for minimizing distortion in shot sleeve designs. In addition to distortion, the thermal gradient in the shot sleeve was analyzed and it was noted that the largest source of heat loss is through the mounting flange attached to the HPDC machine frame, which is not an area typically considered for thermal management.

Investigation of the effectiveness of velocity string to improve gas well productivity

Velocity string (VS) is one of the most common methods to unload water in gas-producing field. In order to understand the behavior affecting production rate, we obtained several parameters including well completion, gas well production data, gas liquid ratio (GLR) and pressure data at tubing and casing head pressure, flowing bottom hole pressure. We then explore the relationship between these parameters against reservoir pressure and perform sensitivity analysis using multiphase steady-state flow simulator to analyze the parameters are the most sensitive to gas production rate. The results show that: (1) at larger inner diameter of the VS, there is a certain increase trend of gas production of gas wells. However, the production rate does not show a linear increase relationship with the larger internal diameter. It will reach certain inflection point before it decreases; (2) the gas production of the VS well is mainly driven by the reservoir pressure, the higher the reservoir pressure, the greater the gas production; (3) the root cause of relatively low initial production rate after small inner diameter coiled tubing VS installation is categorized as an abnormal well startup. This study provides theoretical support for selecting the optimum size and depth of VS to maintain well productivity.

Pulsation incitation and performance investigations for 3D Fin-and-Tube heat pipe heat exchanger by inserting dividing boards for various working fluids

In our previous study, we have shown that a heat pipe heat exchanger system modified from a commercial air-to-air heat exchanger operates without pulsations for working fluids of dielectric HFE-7000 or R134a, or under low heat loads for water, due to the large internal tube diameter of 5.6 mm. To incite pulsation and enhance the thermal performance, a straight dividing copper board is inserted into the straight section of each of the tube to form two semicircular compartments with an effective hydraulic diameter of 3.4 mm. The heat transfer characteristics and thermal performance against the hot air inlet temperature for the novel boarded model and the non-boarded model are experimentally explored with three working fluids (water, HFE-7000 and R134a) under six filling ratios (35%, 38.5%, 50%, 55%, 65%, 71.5%). Because water already works in a PHP mode in the non-boarded model under high heat loads, the thermal performance in the boarded model improved mildly by 2.7%–10.6%. Whereas, for HFE-7000 and R134a, the heat transfer mode is successfully incited from thermosyphon in the non-boarded model into PHP in the boarded model. The most significant thermal performance improvement was observed for HFE-7000 by 8.3%–24.5%. The improvement can be attributed to the switch of heat transfer mode, the generated corners for condensate accumulation, and the additional heat conduction via the copper board.

In vitro testing of a funnel-tip catheter with different clot types to decrease clot migration in mechanical thrombectomy.

Mechanical thrombectomy is the standard treatment for acute ischemic stroke in patients with large vessel occlusion and can be performed up to 24h after symptom onset. Despite high recanalization rates, embolism in new territories has been reported in 8.6% of the cases. Causes for this could be clot abruption during stent retrieval into the smaller opening of a standard distal access catheter, and antegrade blood flow via collaterals despite proximal balloon protection. A funnel-shaped tip with a larger internal diameter was developed to increase the rate of first-pass recanalization and to improve the safety and efficacy of mechanical thrombectomy. This in vitro study compared the efficacy of a funnel-shaped tip with a standard tip in combination with different clot compositions. Mechanical thrombectomy was performed 80 times for each tip, using two stent retrievers (Trevo XP ProVue 3/20 mm, 4/20 mm) and four different clot types (hard vs. soft clots, 0-24h vs. 72h aged clots). Significantly higher first-pass recanalization rates (mTICI 3) were observed for the funnel-shaped tip, 70.0% versus 30.0% for the standard tip (absolute difference, 32; relative difference 57.1%; P < .001), regardless of the clot type and stent retriever. Recanalization could be increased using harder Chandler loop clots versus softer statically generated clots, as well as 0-24h versus 72h aged clots, respectively. The funnel-shaped tip achieved higher first-pass recanalization rates than the smaller standard tip and lower rates of clot abruption at the tip. Clot compositions and aging times impacted recanalization rates.

Constructing high-efficiency transport pathways via incorporating DP-POSS into PEG membranes for pervaporative desulfurization

Constructing high-efficiency transport pathways in polymeric membranes by incorporation of porous fillers has become one of the most prospective methods to break the trade-off effect between membrane selectivity and permeability. Herein, nanoscale dodecyl phenyl polyhedral oligomeric silsesquioxane (DP-POSS) were incorporated into polyethylene glycol (PEG) polymer to fabricate DP/PEG mixed matrix membranes (MMMs) for pervaporation desulfurization. The large internal diameter (0.68 nm) of cage-like DP-POSS particles facilitated the sorption and diffusion of thiophene molecules, and the phenyl groups of DP-POSS might also enhance the preferential sorption of thiophene due to p-π conjugation. The decrease of PEG crystallinity and enhancement of polymer chain mobility contributed to the larger free volume of MMMs, which was also favorable to the mass transfer for small molecules. Accordingly, the resultant DP/PEG-5 MMMs exhibited separation performance with an optimum enrichment factor of 28.9 and permeation flux of 355.3 g/(m2h), achieving 86.5% and 65.0% higher than the pristine membrane. This study might extend strategies to design high-performance MMMs by immobilization nanoscale POSS into polymers for desulfurization.

Use of a sutureless aortic valve in reoperative aortic valve replacement.

ObjectivesManagement of degenerated bioprosthetic aortic valves remains a challenge. Valve-in-valve transcatheter aortic valve replacement (AVR) has limited utility in the presence of small annuli/prosthetic valves. Sutureless valves may offer an advantage over traditional redo AVR by maximizing effective orifice area due to their unique design as well as ease of implant.MethodsTwenty-two patients undergoing redo AVR received a sutureless valve in our institution over the past 5 years. All patients were determined to be poor candidates for valve-in-valve transcatheter AVR due to a combination of small annulus size, low coronary heights, and/or underlying valve characteristics (ie, mechanical valves).ResultsMedian time from implant to redo AVR was 8 years. One patient died within 30 days. In the 13 patients who had a 21 mm or smaller valve explanted, 5 small, 7 medium, and 1 large Perceval valves were implanted (all with larger internal diameters than the explanted valve). The average postoperative gradient of the cohort valves was 14.8 mm Hg compared with 38.8 mm Hg preoperatively.ConclusionsIn addition to their ease of use and rapid deployment, sutureless bioprosthetic aortic valves offer significant physiological advantages in patients with degenerated prosthetic aortic valves and small anatomical annuli. It can also simplify the surgical approach to redo AVR following a Bentall procedure. If long-term durability is confirmed, sutureless valves should be considered in a broader population of patients for both redo and primary aortic valve replacement surgery.

Nests, eggs, clutch size, and nestlings of the Chestnut Seedeater (Sporophila cinnamomea), a vulnerable species of South America

We present information on the nests, eggs, clutch size, and nestlings of the Chestnut Seedeater (Sporophila cinnamomea), a migratory, globally vulnerable species restricted to the natural grasslands of South America. Despite its vulnerability, there is currently a remarkable lack of basic information on this species. We searched for nests from October to March 2018–2019 and 2019–2020 at 2 grassland areas in southern Brazil and monitored a total of 98 nests of 50 different breeding pairs throughout this period. Birds placed their nests on shrubs, clumps, and herbaceous plants, 42–51 cm above humid or dry ground, or water. Nests were low cups built out of native grass stems, inflorescences, and rootlets, held together with spider webs. Nests measured 4.86 cm (SD 0.40) largest internal diameter, 4.17 cm (SD 0.37) smallest internal diameter, 6.31 cm (SD 0.57) largest external diameter, 5.42 cm (SD 0.51) smallest external diameter, 4.04 cm (SD 0.45) internal height, and 4.74 cm (SD 0.52) external height. Clutches had 1–3 eggs. Eggs were mostly ovate, with a whitish to light beige background mottled with blotches and spots of darker beige and brownish tints. The mean egg size was 16.15 mm (SD 1.07) by 12.11 mm (SD 0.34) (n = 23). Results are part of ongoing research in the southern Brazilian grasslands, which aims to fill the gaps in the knowledge of the breeding biology of Chestnut Seedeater and thereby contribute to its conservation.

Impact of gender and age on inner diameter of arteries forming circle of Willis assessed by multidetector CT

Introduction: The circle of Willis (CoW), which is located at the base of the brain is the most important anastomosis between the internal carotid and vertebral system. It is the main distributor of blood to the brain. Methods: CT head and CT angiography were performed using standard scan parameters. Only the tests with normal radiological reports and appropriate technical standards were included in the study. Component of circle of Willis: Anterior cerebral artery (ACA), Middle cerebral artery (MCA), Anterior communicating artery (Acom), Posterior Communicating artery (PCom), Basilar artery (BA) and Posterior cerebral artery (PCA) were identified and their internal diameter were measured. Results: Basilar artery was the artery with largest internal diameter with mean diameter of 2.5 ±0.52 mm. Men had significantly larger arterial sizes than women in all of the intracranial arteries examined except right PCom, Left PCom and right MCA. Right ACA had significantly larger internal diameter in &lt;40 years’ age group. BA, left PCA, Bilateral PCom and MCA showed larger diameter in age group ≥40 years. Conclusion: Men had significantly larger arterial sizes than women in all of the intracranial arteries examined except right PCom, Left PCom and right MCA.

Refractive Index Sensors Based on Long-Period Grating in a Negative Curvature Hollow-Core Fiber.

Long-period optical fiber gratings (LPGs) are one of the widely used concepts for the sensing of refractive index (RI) changes. Negative curvature hollow-core fibers (NCHCFs), with their relatively large internal diameters that are easy to fill with liquids, appear as a very interesting medium to combine with the idea of LPGs and use for RI sensing. However, to date, there has been no investigation of the RI sensing capabilities of the NCHCF-based LPGs. The results presented in the paper do not only address this matter, but also compare the RI sensitivities of the NCHCFs alone and the gratings. By modeling two revolver-type fibers, with their internal diameters reflecting the results of the possible LPG-inscription process, the authors show that the fibers’ transmission windows shift in response to the RI change, resulting in changes in RI sensitivities as high as −4411 nm/RIU. On the contrary, the shift in the transmission dip of the NCHCF-based LPGs corresponds to a sensitivity of −658 nm/RIU. A general confirmation of these results was ensured by comparing the analytical formulas describing the sensitivities of the NCHCFs and the NCHCF-based LPGs.

Ventilation strategies for front of neck airway rescue: an in silico study

BackgroundDuring induction of general anaesthesia a ‘cannot intubate, cannot oxygenate’ (CICO) situation can arise, leading to severe hypoxaemia. Evidence is scarce to guide ventilation strategies for small-bore emergency front of neck airways that ensure effective oxygenation without risking lung damage and cardiovascular depression. MethodsFifty virtual subjects were configured using a high-fidelity computational model of the cardiovascular and pulmonary systems. Each subject breathed 100% oxygen for 3 min and then became apnoeic, with an obstructed upper airway. When arterial haemoglobin oxygen saturation reached 40%, front of neck airway access was simulated with various configurations. We examined the effect of several ventilation strategies on re-oxygenation, pulmonary pressures, cardiovascular function, and oxygen delivery. ResultsRe-oxygenation was achieved in all ventilation strategies. Smaller airway configurations led to dynamic hyperinflation for a wide range of ventilation strategies. This effect was absent in airways with larger internal diameter (≥3 mm). Intrapulmonary pressures increased quickly to supra-physiological values with the smallest airways, resulting in pronounced cardio-circulatory depression (cardiac output <3 L min−1 and mean arterial pressure <60 mm Hg), impeding oxygen delivery (<600 ml min−1). Limiting tidal volume (≤200 ml) and ventilatory frequency (≤8 bpm) for smaller diameter cannulas reduced dynamic hyperinflation and gas trapping, preventing cardiovascular depression. ConclusionsDynamic hyperinflation can be demonstrated for a wide range of front of neck airway cannulae when the upper airway is obstructed. When using small-bore cannulae in a CICO situation, ventilation strategies should be chosen that prevent gas trapping to prevent severe adverse events including cardio-circulatory depression.

EXPERIMENT STUDY ON SEISMIC PERFORMANCE OF RUBBER FLEXIBLE PIPES FOR SEISMICALLY ISOLATED BUILDINGS

Rubber flexible pipes have been increasingly used in seismically isolated buildings. Whether it could work normally after the earthquake directly affects the function of the building. The vertical rubber flexible pipeline is selected as the research object. Base on the deformation requirement of 400 mm, the seismic performance test is carried out considering the influence of two nominal inner diameters and four different design lengths. The seismic damage evolution model, deformation and bearing capacity characteristics of this type of pipeline are compared and analyzed. The test results indicate that: The pipes with smaller design length cannot meet the expected deformation target. Such pipes experienced two key states： pipe stretching and single-sided fracture. And such pipes must be replaced after the earthquake; For pipes with a design length consistent with the code recommendations, deformation requirements can be met; The quantitative relationship between the nominal inner diameter and design length of the pipeline and its horizontal deformation ability was obtained through regression analysis; For pipes with an identical design length, the nominal inner diameter of the pipeline and the horizontal ultimate load at the time of failure are positively related. Meanwhile the ratio of ultimate load for the pipe with a large and small nominal internal diameter is smaller than the ratio of correspond inner diameter.

Anatomical Variations of Radial Artery-Its morphology and Clinical Implications

Background: The radial artery is the smaller terminal branch of the brachial artery. It is one of the most commonly used arteries for various interventions. Anatomical variations exist and can predispose patients to iatrogenic injury if the operator is unaware of normal radial artery morphology. The present study focuses on giving detailed information about radial artery measurements in our local population.&#x0D; Methods: This was a cross-sectional observational study, conducted in the anatomy department of Jinnah Medical College Peshawar from 2017 to 2018. This study was conducted on 42 formalin-fixed cadavers, yielding 84 upper limbs. The radial artery was dissected and studied; length, external and internal diameters were measured. Data was entered in SPSS v20 and analyzed. Results: The mean age of the study population was 36 ± 11.25. Male to female ratio was 1:1. The most common site of origin of the radial artery was distal to head of the radius. The right radial artery was longer than the left. The right radial artery was broader in males as compared to females with a p-value of &lt;0.05. The external and internal diameters of the radial artery decreased gradually from start to the endpoint for both the genders. The external diameters of the left radial artery were greater than those on the right side. The right radial artery had a larger internal diameter than the left side.&#x0D; Conclusion: The anatomy and morphology of radial artery have many documented variations. Radiologist and surgeons should have a good understanding of normal morphological variations of radial artery.

Molecular dynamics simulation studies of displacement cascade induced defects in gold nanotubes

In order to investigate the defects induced by displacement cascade in gold nanotubes, primary knock-on atoms with kinetic energies of 1 keV were introduced at the exterior surface of the nanotubes. The evolution of the collision cascade as well as the defects generated in the nanotube were studied using molecular dynamics simulation. We found that point defects and stacking faults were induced by the cascade. The interior surface of the nanotube acts as the sinks to absorb the point defects as the same as the exterior surface does, especially when the distance between them is decreased. Consequently, both the two surfaces influence the time evolution and the residual number of point defects in the nanotubes. In the gold nanotubes with fixed external diameter, the number of interstitials is decreased with the internal diameter increasing, while the number of vacancies does not show a clear trend with the variation of the internal diameters. The probability of formation of stacking faults is higher in gold nanotubes with larger internal diameters which caused by the fact that the formation of stacking faults is facilitated by the interior surface. The results show that, due to the specific geometry of the nanotubes, the evolution and the production of the cascade-induced damage has its own features.

Frequency Domain-optical Coherence Tomography of Coronary Arteries Using a Diluted Iodinated Contrast-saline Mix with 5-Fr Guide Catheters.

BackgroundOptical coherence tomography (OCT) is currently mostly performed using 6-Fr coronary guide catheters via femoral access. Catheters with such large internal diameters are necessary to deliver viscous contrast media and achieve sufficient red blood cell washout. Currently, undiluted iodinated contrast media (15 mL/injection) is used to clear the coronary arteries of red blood cells (RBCs). This leads to an increase in the total amount of contrast used and often the need for femoral artery access. Our objective is to assess the feasibility of performance of OCT using a 5-Fr guide catheter via radial access using diluted iodinated contrast.MethodsWe present a case series of 11 patients where second-generation frequency domain (FD)-OCT was used to assess the coronary arteries using a novel 70:30 dilution mixture of iodinated contrast medium with heparinized normal saline. All procedures were performed with a 5-Fr coronary guide catheter via the radial artery approach.ResultsAll procedures were successfully performed vial radial access with good quality imaging obtained. The target vessel was the left anterior descending artery in eight patients, the right coronary artery in two patients, and the left main coronary artery in one patient. OCT resulted in a change in management in 7/11 (64%) patients; no complications were reported with OCT. On average, 10 mL of contrast was used per injection.ConclusionsThe current study demonstrates the feasibility of FD-OCT using 5-Fr guide catheters and diluted iodinated contrast media. This approach lowers contrast exposure and potentially decreases vascular complications without sacrificing image quality.

Numerical Simulation of Stagger Spinning for D406A High-Strength Steel

Metal spinning process is widely used because of its low power requirement to producing complex symmetry components. In this paper, a modified 3D finite element(3D-FE) model is developed under the FE software environment based on characteristics of stagger spinning process. Analysis of the multi-pass spinning deformation mechanism and the effects of spinning parameters on spinning deformation is carried out. The results show that, large internal diameter of tube blank and low dimensional accuracy are caused by too little feed rate of spinning roller, especially for thin-walled tube. But if the feed rate is larger than 60mm/min, large spinning forces and instability appear. Strain rate and forming instability increase with the increase of rotational speed of mandrels, on the other hand, more obvious friction leads to bigger strain of surface of tube blank. With the radius of corner of spinning roller getting 13mm, the extensive overlaps lead to the improvement of spinning efficiency, while low forming quality accompanied by the large spinning forces occurs. Cutting phenomena leads to worse surface quality even tends to crack with the radius of corner of spinning roller being smaller than 8mm. An ideal combination of process parameters is obtained: the roller feed rate is 50mm/min, the rotational speed of mandrel is 40rad/min, the radius of corner of spinning roller is 10mm.

A Tautoleptic Approach to Chiral Hydrogen-Bonded Supramolecular Tubular Polymers with Large Cavity.

A new strategy towards tubular hydrogen‐bonded polymers based on the self‐assembly of isocytosine tautomers in orthogonal directions is proposed and experimentally verified, including by 1H fast magic‐angle spinning (MAS) solid‐state NMR. The molecular tubes obtained possess large internal diameter and tailor‐made outer functionalities rendering them potential candidates for a number of applications.

FORMULATION DEVELOPMENT AND CHARACTERIZATION OF SNAKEHEAD FISH POWDER IN ORAL DOUBLE EMULSION

Objective: Snakehead fish has been scientifically proven to increase levels of albumin and boost the immune system so that the formulation development is required. The objective of this study was to formulate and characterize snakehead fish powder (SFP) in the form of the oral double emulsion.Methods: The manufacture of snakehead fish powder used the conventional method with dry heating at 50 °C. Characterization of SFP utilized proximate analysis method per 3 g of SFP. The double emulsion preparation was carried out by mixing 30% of the primary emulsion (w/o) into 70% of the secondary emulsion (w) to form the w/o/w emulsion. This preparation was prepared in 4 formulas having variations in Tween 80 concentrations at the secondary emulsions of 0.7%, 3.5%, 7.0% and 10.5% w/v, respectively using the spontaneous emulsification method. After that, all formulations were doing some tests, i.e. organoleptic test, pH, viscosity, flow types, globular diameter test and stability tests.Results: The results of proximate analysis every 3 g of SFP have obtained the contents of protein, 16.89%, lipid 24.52%, water 1.73% and ash 1.05%. Based on the optimization of the formula, the preparation of F4 with the content of Tween 80 at 10.5% secondary emulsion is the best formula due to slow phase separation, pH 7, unchanged organoleptic properties, large internal and external globular diameter (6.35 μm and 8.9 μm), as well as having a high viscosity value (1569.84 p) which correspond to pseudo plastic flow.Conclusion: The novelty of SFP can be developed as double emulsion orally based on the results of characterization and evaluation of double emulsion.

Features of injection and chromatographic separation of samples in high boiling viscous organic solvents using the capillary columns at a low split ratio

The features of injection and gas chromatographic separation of stock analytes in their solutions in high boiling viscous polar organic solvents (on the example of 1,3-butanediol) using a short capillary column of large internal diameter (Megabore type) at low split ratios are considered. The manifestation of so-called discrimination effects is confirmed, with the main of them being the dependence of absolute peak areas vs . injection temperature as well as similar dependence of relative peak areas in different solvents. However, these effects are manifested in a lesser degree than the same effects for the samples dissolved in low boiling solvents. It is demonstrated that the dependencies of peak areas vs . injector temperature ( S = aT + b ) are principally different for solvents with various boiling points. Thus, for the solutions of butyl acetate, cyclohexanone, anisol, butyl butyrate, and acetophenone in low boiling 2-propanol the linear dependencies S ( T ) are revealed for the injector temperature range of 120-180°С only (with correlation coefficients r = 0.986 – 0.999), while at the higher injector temperatures (210-240°С) the significant deviations from linearity are typical. At the same time, the solutions of the same components in higher boiling 1,3-butanediol demonstrate the linear S ( T ) dependencies within the whole temperature range (120-240°С). It is confirmed that the discrimination effects have no significant influence on the results of gas chromatographic analyses of the samples in high boiling solvents if the method of internal normalization is used. The main uncertainties of the results are caused by the column’s overloading with the solvent, which leads to the broadening and asymmetry of its peaks and their overlapping with the peaks of some analytes. DOI: http://dx.doi.org/10.15826/analitika.2018.22.3.005 Keywords : High boiling viscous organic solvents, gas chromatographic analysis, capillary columns, discrimination effects (Russian) Igor G. Zenkevich, Eugene Leleev St. Petersburg State University, Russian Federation, 198504, St. Petersburg, Universitetskii prosp., 26