Passage Of Liquid Research Articles

Concrete Gas Permeability: Implications for Hydrogen Storage Applications

Concrete is widely utilized across various industries as a containment material. One essential property related to its performance is permeability, which determines its ability to allow the passage of gases or liquids through its pores and capillaries and even the transmission of aggressive agents. This study focused on investigating the permeability of gases with varying atomic weights and molecular volumes, such as helium, nitrogen, oxygen, and argon, to pass through concrete. The primary objective was to determine the significance of variation in permeability and to evaluate and differentiate their behavior. To achieve this, concrete test specimens were employed, and factors such as cold joint impact, gas pressure, and specimen saturation levels were considered. Throughout the study, changes in weight, specimen humidity, resistivity, and ultrasonic pulse velocity were monitored. The findings suggested that within concrete, the variation in permeability for these gases is negligible. By utilizing the acquired data, the present study estimated the permeability of hydrogen through mathematical models based on gas pressure and concrete thickness. These insights contribute to a deeper comprehension of concrete gas permeability and its potential impact on improving hydrogen containment.

Effect of Brosimum alicastrum Foliage on Intake, Kinetics of Fermentation and Passage and Microbial N Supply in Sheep Fed Megathyrsus maximus Hay.

An experiment was carried out to assess the effect of the incorporation of sun-dried foliage of Brosimum alicastrum into rations based on hay of Megathyrsus maximus on intake, rumen fermentation, kinetics of passage, microbial nitrogen supply to the small intestine, apparent digestibility in Pelibuey hair sheep. Four rations were randomly allotted to four rumen-cannulated lambs (BW = 37.4 ± 4.9 kg) using a 4 × 4 Latin square design to assess the effect of increasing levels (0, 15, 30 and 45% DM basis) of foliage of Brosimum alicastrum on a basal ration of M. maximus. Organic matter intake and water consumption increased linearly (p < 0.01) with increasing levels of B. alicastrum in the ration. The rate and potential extent of rumen fermentation of OM and CP of B. alicastrum were 10.6%/h and 86.6% and 11.4%/h and 95.2%, respectively, but no effect (p > 0.05) was found on the potential rumen degradation of DM (40.2%) or on the rate of degradation of DM (0.033%/h) of M. maximus, although a positive effect was found in the rumen degradation rate of NDF (p < 0.05). VFA and ammonia concentration in the rumen and the rate of passage of solids and liquids through the rumen (k1) increased linearly (p < 0.01) with increasing levels of B. alicastrum. Rumen pH was not affected by the incorporation of B. alicastrum (p > 0.05). Microbial nitrogen supply to the small intestine (p < 0.001), apparent digestibility of dry matter (p < 0.01) and NDF (p < 0.05) of the rations were also significantly increased as a result of the incorporation of B. alicastrum foliage. Results from this experiment suggest that the foliage of Brosimum alicastrum can be readily incorporated at around 30% of the ration of dry matter in hair sheep with beneficial effects on feed intake, rate of passage and microbial N supply to the lower tract.

Quando il versamento pleurico origina... dall'addome

We report the case of a 13-year-old girl who suffered of complicated appendicitis, treated by laparoscopic appendectomy, who then develops a bilateral pleural effusion, requiring a chest drain. Pleural exudative effusion is a rare complication of perforated appendicitis; it’s caused by irritation of the diaphragm and by the passage of liquids from the abdominal cavity to the thoracic one, favored by pneumoperitoneum and Trendelenburg position.

Faecal incontinence-a comprehensive review.

Faecal incontinence (FI) is a distressing and often stigmatizing condition characterised as the recurrent involuntary passage of liquid or solid faeces. The reported prevalence of FI exhibits considerable variation, ranging from 7 to 15% in the general population, with higher rates reported among older adults and women. This review explores the pathophysiology mechanisms, the diagnostic modalities and the efficiency of treatment options up to date. A review of the literature was conducted to identify the pathophysiological pathways, investigation and treatment modalities. This review provides an in-depth exploration of the intricate physiological processes that maintain continence in humans. It then guides the reader through a detailed examination of diagnostic procedures and a thorough analysis of the available treatment choices, including their associated success rates. This review is an ideal resource for individuals with a general medical background and colorectal surgeons who lack specialized knowledge in pelvic floor disorders, as it offers a comprehensive understanding of the mechanisms, diagnosis, and treatment of faecal incontinence (FI).

Liquid-infused interfacial floatable porous membrane as movable gate for ultrafast immiscible oil/water separation.

Liquid separation methods are widely used in industrial and everyday applications, however, their applicability is often constrained by low efficiency, membrane fouling, and poor energy efficiency. Herein, a conceptually novel liquid-infused interfacial floatable porous membrane (LIIFPM) system for high-performance oil/water separation is proposed. The system functions by allowing a liquid to wet and fill a superamphiphilic porous membrane, thereby creating a stable liquid-infused interface that floats at the oil/water interface and prevents the passage of immiscible liquids. The lower-layer liquid can outflow directly, while the flow of the upper-layer liquid is stopped by the membrane. Remarkably, the efficiency of the LIIFPM system is independent of the membrane pore size, enabling ultrafast immiscible oil/water separation in an energy-saving and antifouling manner.

Variation in the contact angle of zinc oxide nanostructures with the passage of time

The development of clean materials has increased; these materials present a surface modification that makes them neat and easy to clean. The direct improvement in the impermeability of materials is generated by manipulating the structures present on the surfaces, generating selfcleaning coatings (hydrophobic surfaces). The modification can be developed by superficially synthesizing nanostructures of specific shapes on some solid that prevent the passage of liquids between them, for example, zinc oxide nanowires that exhibit a high contact angle due to their geometry. The synthesis of these nanostructures is low cost and simple, making it a viable alternative to achieve hydrophobic surfaces that are selfcleaning. The present work shows how the synthesis factors of these nanostructures impact their contact angle. Hydrophobic contact angles were obtained in most samples and nanostructures averaging 290 nm and average lengths of 2.2 μm.

PROCESSING OF WELLHEAD CHRISTMAS TREES PIPE HEADER

In this study, the components of the tubing head of the Wellhead Christmas tree are classified. Information on how to install the tubing head to the Christmas tree (oil and gas) is also provided. The tested tubing head ensures the passage of liquid or gas into the spaces between the tubes. They have to control the pressure and conduct the necessary well studies. The tubing header seals and hangs the riser columns, which is especially effective when inserting concentric or parallel columns into the well. As a result of the conducted studies, the tubing head fully controls the flow of the technological liquid. Tubing headers to perform these processes should be manufactured according to the working pressure requirements between 14 and 105 MPa. Using a tubing head, you can connect different numbers of pipelines, as well as control the distribution of the medium flow in the circular zone of the valve. Of the cost-effective methods we have mentioned one is connected to the upper flange of the pipeline column header with a lower mounting fixing component. The design of the tubing head is completed by threaded holes in the body through which you can quickly replace the side valves in the head tube. The tubing head is designed to stop one or more rows of riser (pump and compressor) tubes and is used to perform technological operations during the development, operation and repair of wells. The top of the tubing at the wellhead is screwed into the tubing cap of the Christmas tree (oil and gas). Once installed at the wellhead, the Christmas tree (oil and gas) tubing header is compressed to the allowable pressure for pressure testing the production casing. Tubing head design and strength characteristics are shown in this figure: a) working pressure (7, 14.21, 35, 70 and 105 MPa), b) numbers of pipes lowered into the well (one and two concentric rows of pipes), c) constructions of locking devices (valves and taps) dimensions of the flow section along the trunk (50... 150 mm) and side branches (50... 100 mm). The tubing head holds and takes over the pressure generated between the tubes and can be prohibitive, which is quite dangerous for people's lives and health. Keywords: Christmas tree (oil and gas), tubing header, pressure, flow, wellhead, test, well.

Determining the effect of mineral scaling formation under different injection water sources on the performance of Mishrif carbonate reservoir in Halfaya oilfield, Southern Iraq

The chief source of the oilfield scale is the mixing of incompatible waters. This study demonstrated that mixing the reservoir of Mishrif formation (Halfaya oilfield) with six types of injection water sources, including Tigris River water, producing water formation, Gulf seawater, Marshes water, Middle Kirkuk formation water, and Main Outfall Drain water (AL-Masab AL-Aam Channel), leads to the formation of salt crusts that cause the reduction of reservoir rock permeability. According to the Piper diagram, the Mishrif formation water of all extant water samples was of the sodium chloride type (NaCl), except for HF-81, which was between (NaCl) and mix (CaMgCl) type. A geochemical simulation model of water alignment (PHREEQC) was used to simulate this problem, and it revealed the mineral scaling from mixing processes. These minerals precipitate in rock pores and clog them, which then cause damage to the petrophysical properties of the reservoir and prevent the passage of liquids. Results showed that the best water types used for injection are Middle Kirkuk formation water, followed by the general downstream, then Gulf seawater, but treatment before injection is needed. The study of geochemical modeling method can help to better understand scaling issues by efficiently identifying the best injection water from various selected types with the lowest possible cost, which in turn improves oil production.

Stents in Veterinary Medicine

Stenting in veterinary medicine has been a rapidly growing method of interventional surgery for several years. This procedure is usually performed in the respiratory and urinary tracts, but there are cases of stenting of blood vessels or gastrointestinal structures. It is based on maintaining the permeability of a given tubular structure, thus allowing the passage of gas or liquid. This procedure is often performed as a first-line treatment in situations where pharmacological agents do not work and as an alternative method, often cheaper than the classically performed ones. There are also cases where stenting is used as a palliative treatment, e.g., to enable defecation in colonic obstruction due to tumour infiltration of the colon wall. Stenting is often a life-saving or comfort-improving procedure for animals, but one should also be aware of possible postoperative complications and be prepared for any adversity. For this reason, this review provides an insight into the current knowledge in veterinary medicine about stenting and the consequences associated with this procedure.

Numerical experiments on the determination of rational range of mode parameters for the effective dewatering of various screening surfaces

Dehydration of mineral raw materials on a vibrating screen occurs as a result of the passage of liquid through the cells of the screening surface. With fine and ultrafine screening, this process is hindered by the surface tension of the liquid. None of the screening theories makes it possible to determine which vibration excitation modes ensure dehydration. With the help of numerical experiments on a mathematical model, the influence of vibration excitation modes on the intensity of the passage of liquid through the cells of various screening surfaces during dehydration on a vibrating screen was studied. In doing so, two tasks were solved: 1) determination of the amplitude and frequency of vibration excitation, when the required balance of water and the size of the cells of the screening surface are set; 2) determination of the remaining water on the screening surface depending on the cell size of the screening surface, the amplitude and frequency of vibration excitation. The developed mathematical model made it possible to solve both problems. On the basis of calculations and analysis, rational range of mode parameters of the vibrating screen for effective dehydration of various screening surfaces was established. The calculation algorithm is implemented on the basis of a mathematical model in the PC program «Sifting Surface» in C ++ with the connection of mathematical libraries and «Excel». The results of calculations, demonstration of the possibilities of various screening surfaces and modes are shown in the figures, which show the dependences of the residual water on the amplitude and frequency vibration excitation parameters. It is established that the vibro-impact effect, in comparison with the harmonic effect, provides better results in cleaning the cells from the liquid retained in them by surface tension forces, under less intensive modes. The results obtained will be used in the development of a mathematical model of dehydration and a method for calculating technological parameters that ensure effective removal of liquid during fine and ultrafine screening of mineral raw materials, as well as to determine the rational design and dynamic parameters of the screen.

Work needed to force the water-air interface down in the re-entrant structured capillary pore

The re-entrant structure of the membrane surface has attracted researchers' attention recently, due to its ability to make the membrane surface more wetting resistant-either in water or in liquids of low surface tension. The underlying principle of this approach is that an energy barrier has to be overcome when the transition occurs from the Cassie Baxter state to the Wenzel state of the rough membrane surface, which prevents the passage of liquid through the membrane pore. In this work, the energy barrier was evaluated for the cone-shaped pore based on Young's theory of the capillary force. It was found that the energy barrier is enhanced by increasing the angle of the apex of the cone, the pore length, and the contact angle. The effects of the first two geometrical factors, the angle of apex of cone and pore length, are much stronger than the effect of the contact angle. It is believed that this work will offer a guideline for the rational membrane design to reduce, and even prevent, the pore wetting of membranes, particularly for oil/water separation and membrane distillation.

ВЛИЯНИЕ ИЗНОСА ПАРЫ ТРЕНИЯ НА СРОК СЛУЖБЫ МАШИНЫ

The influence of the degree of wear of the friction pair on the durability and resource of mechanisms and machines is considered. The passage of liquid or gas, a decrease in the discharge pressure in the cylinders, runout and dynamic loads on components and parts increase with the wear of friction pairs, which as a result leads to a decrease in the durability and resource of machines

Laparoscopic Heller Myotomy and Toupet Fundoplication.

Esophageal achalasia is a primary motility disorder of unknown origin. The goal of treatment is to eliminate the resistance caused by a non-relaxing lower esophageal sphincter, therefore allowing passage of foodand liquid from the esophagus into the stomach. A myotomy with a partial fundoplication (anterior Doror posteriorToupet) is considered the standard of care for patients with achalasia. In the following review, we describe the indications and technique for a posterior partial fundoplication (Toupet).

Evaluation of swallowing in the critically ill patient. The right time

Swallowing is defined as the passage of liquid and solid substances from the mouth to the stomach, and, within this process, there are four stages (anticipatory, oral, pharyngeal and esophageal) that will be responsible for carrying out said activity safely and effectively. If there is any alteration in any of these stages, it is called dysphagia, and consequently, the patient could present bronchial aspiration, malnutrition and dehydration; likewise, prolong the days of hospital stay and increase morbidity and mortality. The patient admitted to the Intensive Care Unit (ICU), may require mechanical ventilation support through an oro-tracheal tube or tracheostomy, which affects the structures involved in the act of swallowing (rigidity, weakness, alteration in subglottic pressure, sensitivity and edema) and its interaction with breathing, triggering a possible dysphagia associated with mechanical ventilation (VAMD). This involvement can occur at the time of extubation of the patient (post-extubation dysphagia) or if the patient has a tracheostomy cannula.

МАТЕМАТИЧНЕ МОДЕЛЮВАННЯ ВЗАЄМОДІЇ СІТЧАСТИХ РОЗДІЛЮВАЧІВ ФАЗ С ГАЗОВИМИ ПУЗИРЯМИ В УМОВАХ ЗМІННОГО ПОЛЯ МАСОВИХ СИЛ

Modern multi-purpose spacecraft for several years must perform complex and diverse tasks in outer space. At the same time, it is necessary to turn on jet engines dozens of times in conditions of practical weightlessness. At the time of starting the engine, the liquid fuel is mixed randomly with the boost gas. In this case, it is impossible to guarantee the contact of the drainage hole with the gas phase, and the drain hole with the fuel. To solve this problem, it is proposed to use various, so-called means of ensuring the continuity of fuel (MECF). The effectiveness of monitoring the position of the liquid in the flight conditions of the aircraft in the passive section of the trajectory is determined by the ability of the MECF to ensure the discharge of fuel from the tank without gas inclusions at any required time with a given flow rate and in the required amount with a minimum volume of unselected residues.&#x0D; The article deals with the features of the functioning of the SOST of the inertial type, which includes mesh phase separators (MPS). The need to use the MPS is due to the possibility of the gas phase entering the drain line, both in the passive section of the trajectory and at the stage of switching on the main engines, which can lead to a disruption of their launch. When fuel moves into the drain line, bubbles remain on the mesh surface and prevent the passage of liquid. &#x0D; The article builds a mathematical model of the behavior of gas bubbles on the surface of the MPS in the flow of a viscous liquid. On the basis of the constructed mathematical model, the corresponding numerical calculations were carried out. The proposed method of engineering calculation makes it possible to determine such a MECF design that excludes the possibility of "contamination" of the surface of the MPS by gas bubbles and the disruption as a result of this normal functioning of the fuel supply system to the engines of spacecraft.

Leakage pressures for gasketless superhydrophobic fluid interconnects for modular lab-on-a-chip systems

Chip-to-chip and world-to-chip fluidic interconnections are paramount to enable the passage of liquids between component chips and to/from microfluidic systems. Unfortunately, most interconnect designs add additional physical constraints to chips with each additional interconnect leading to over-constrained microfluidic systems. The competing constraints provided by multiple interconnects induce strain in the chips, creating indeterminate dead volumes and misalignment between chips that comprise the microfluidic system. A novel, gasketless superhydrophobic fluidic interconnect (GSFI) that uses capillary forces to form a liquid bridge suspended between concentric through-holes and acting as a fluid passage was investigated. The GSFI decouples the alignment between component chips from the interconnect function and the attachment of the meniscus of the liquid bridge to the edges of the holes produces negligible dead volume. This passive seal was created by patterning parallel superhydrophobic surfaces (water contact angle ≥ 150°) around concentric microfluidic ports separated by a gap. The relative position of the two polymer chips was determined by passive kinematic constraints, three spherical ball bearings seated in v-grooves. A leakage pressure model derived from the Young–Laplace equation was used to estimate the leakage pressure at failure for the liquid bridge. Injection-molded, Cyclic Olefin Copolymer (COC) chip assemblies with assembly gaps from 3 to 240 µm were used to experimentally validate the model. The maximum leakage pressure measured for the GSFI was 21.4 kPa (3.1 psig), which corresponded to a measured mean assembly gap of 3 µm, and decreased to 0.5 kPa (0.073 psig) at a mean assembly gap of 240 µm. The effect of radial misalignment on the efficacy of the gasketless seals was tested and no significant effect was observed. This may be a function of how the liquid bridges are formed during the priming of the chip, but additional research is required to test that hypothesis.

Percolation and tortuosity in heart-like cells

In the last several years, quite a few papers on the joint question of transport, tortuosity and percolation have appeared in the literature, dealing with passage of miscellaneous liquids or electrical currents in different media. However, these methods have not been applied to the passage of action potential in heart fibrosis (HF), which is crucial for problems of heart arrhythmia, especially of atrial tachycardia and fibrillation. In this work we address the HF problem from these aspects. A cellular automaton model is used to analyze percolation and transport of a distributed-fibrosis inflicted heart-like tissue. Although based on a rather simple mathematical model, it leads to several important outcomes: (1) It is shown that, for a single wave front (as the one emanated by the heart's sinus node), the percolation of heart-like matrices is exactly similar to the forest fire case. (2) It is shown that, on the average, the shape of the transport (a question not dealt with in relation to forest fire, and deals with the delay of action potential when passing a fibrotic tissue) behaves like a Gaussian. (3) Moreover, it is shown that close to the percolation threshold the parameters of this Gaussian behave in a critical way. From the physical point of view, these three results are an important contribution to the general percolation investigation. The relevance of our results to cardiological issues, specifically to the question of reentry initiation, are discussed and it is shown that: (A) Without an ectopic source and under a mere sinus node operation, no arrhythmia is generated, and (B) A sufficiently high refractory period could prevent some reentry mechanisms, even in partially fibrotic heart tissue.

Physical, chemical, mechanical, and micromorphological characterization of dental needles.

BackgroundIn anesthetic techniques, touching bones can cause needle bending. Theoretically, a needle should support such deflection without fracturing. However, it is possible that a needle may fracture depending on the quality and type of needle used. This study evaluated the physical, chemical, and micromorphological characteristics of long and short dental anesthetic needles, as well as the mechanical properties of flexural load and bending resistance when needles are subjected to different bending angles.MethodsLong and short needles (30G, Jets, Misawa, Selekto, Terumo, Unoject and 27G, Dencojet, Injex, Jets, Misawa, Procare, Setoject XL, Terumo) were evaluated. Scanning electron microscopy was used to evaluate the needle bevels and energy-dispersive X-ray spectroscopy was used for the chemical analysis of needle compositions. Flexural loading and bending strength assessments were performed using a universal testing machine by bending the needles (n = 5) to angles of 30°, 60°, or 90°, or until fracture occurred.ResultsThe Injex 27G, Jets 27G, and Septoject XL 27G needles were all less than 30 mm in length. There were small percentage variations in the chemical compositions of the needles. Superior smoothness was observed for the Unoject 30G needle, which exhibited the highest fracture resistance at 60°. The Jets 30G needle exhibited greater resistance to fractures at 90°. The Procare 27G needle exhibited the highest load resistance to bending, followed by the Septoject XL 27G needle, and both needles were tied for the lowest fracture resistance. No needle fractured when bent to 30° or at less than three bends to 60° or 90°.ConclusionsGreater needle resistance to bending increases the probability of early fracturing. Thinner and shorter needles are more resistant than longer and thicker needles. Performing a single bend does not result in any significant risk of fracture or obliterate the lumen, allowing for the continued passage of anesthetic liquid.

Peri-Operative Intracameral Antibiotics: The Perfect Storm?

In our University journal club we discussed a large, retrospective study of cataract surgery endophthalmitis rates before and after instituting the use of an intracameral fluoroquinolone antibiotic. We identified several factors involved in the use of off-label, compounded moxifloxacin in intraocular surgery. The introduction of phacoemulsification for cataract surgery led to the potential for smaller incisions. Intraocular lens technology improved to allow for foldable lenses, obviating the requirement to enlarge the incision. This allowed for clear corneal incisions, which unfortunately allow bidirectional passage of liquid. Preservatives were introduced into multi-dose ophthalmic products in the mid 20th century to retard microbial growth. However, more recently, chronic use of benzalkonium chloride has led to concerns about concerns about conjunctival toxicity, especially in patients with ocular surface disease. In the formulation of ocular moxifloxacin, developers were able to develop a "self-preserved", multi-dose product. Other concerns with eyedrops include varying levels of adherence and performance, and the expansion of compounding pharmacies from a named-patient basis to widespread national delivery, with concerns for lower quality. Integrating these factors, use of intracameral moxifloxacin as a prophylactic during cataract and other anterior segment surgery has become a standard of care in much of the U.S. We are concerned that the current position is on a narrow ledge-the standard of care for millions of surgeries each year based upon off-label, compounting use of a single product. We discuss possible ramifications and solutions to this public health issue.

NANOTECNOLOGIA: SIMULAÇÃO DE SUPERFÍCIES HIDROFÓBICAS POR MEIO DE MATERIAIS ALTERNATIVOS

As superfícies hidrofóbicas têm despertado um grande interesse em variadas áreas devido à sua importância e a suas potenciais aplicações industriais. As moléculas hidrofóbicas normalmente são apolares, portanto, não há atração entre as moléculas de água que são polares. Esses materiais que não possuem uma boa interação com a água já são comercializados mundialmente: camisas que não ficam sujas, sapatos que não permitem a passagem de líquidos, vidros de carros que facilitam o deslize da água tendo uma melhor visualização em dias chuvosos e até mesmo na medicina com microdispositivos que atacam exatamente o local desejado. A molhabilidade da superfície de um material é uma propriedade que está presente também no cotidiano, e muitas vezes não são facilmente visualizadas, estando presente em diversas plantas, penas das aves e até mesmo nas asas de alguns insetos. Dessa forma considera-se que a Nanotecnologia está presente no cotidiano da população e é indispensável que esse assunto seja levado para as aulas de Química do ensino médio. De acordo com alguns estudos compete ao ensino médio o papel essencial na formação do cidadão através de temas relevantes e atuais como a Nanociência e a Nanotecnologia, além de outros de forte relação com aspectos sociais e ambientais. Por esse motivo apresentamos esse trabalho, no qual mostramos alguns materiais que podem ser utilizados para simular algumas práticas Nanotecnológicas voltadas para o ensino. A pesquisa foi realizada com professores do curso de Licenciatura em Química e integrantes do GT de experimentação do PDVL. Foi possível observar que os materiais realmente simulam superfícies hidrofóbicas e são de fácil acesso podendo ser utilizados por professores como ferramenta auxiliadora no ensino de Química.