Auswahl der wissenschaftlichen Literatur zum Thema „Liquid Christals“

Eighteen-month-old seedlings of Christmas Bell (Blandfordia grandiflora Sm.) in 800-ml containers were top dressed with 8- to 9-month Osmocote controlled-release fertilizer 18N-2.6P-10K at 0, 0.625, 1.25, 2.5, 5.0, or 10 kg·m-3. Other plants were fertilized once or twice weekly with a complete liquid fertilizer supplying 100 mg N/liter based on an N : K ratio of either 1:0.6 or 1:1.5. The former ratio was the same as the Osmocote while the latter was the N : K ratio in tops of healthy wild-growing plants of B. grandiflora. The highest fresh weights occurred at the Osmocote rate of 5 kg·m-3 and with the once-weekly liquid feed of 1 N : 1.5 K ratio. Plants fertilized with low rates of Osmocote were pale green but had extensive root systems that were white and predominantly fibrous. As the rate of Osmocote was increased, plants became greener and produced smaller root systems in which fleshy storage organs were predominant over fibrous roots.

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.

The article considers a method for calculating the hydrodynamic force, which makes it possible to estimate the value of this force during the flow of liquid in the channels of an adjustable valve, using numerical calculation methods. This method allowed us to justify the choice of the direction of fluid flow in the valve, based on the conditions for minimizing its force effect on the drive controlling the position of the shut-off and control element (ZRE). Also, the method of balancing the pressure level was considered, which allows unloading the ZRE and reducing the value of the hydrodynamic force for different variants of fluid flow in the valve.

The key reason to make this research is to find solutions for mechanical impurities, or commonly sand clogging in christmas trees. As it’s known, christmas trees are equipment made for controlling flow of oil and gas, which consists of several gauges and valves for specific purposes. This equipment installed on wells are constantly clogged with various impurities. These mechanical consistency interrupt christmas tree’s work and cause wears and tears which leads to failure of system and overall oil production delay. Thus, frequent maintenance is required. There are two main ways to release the clogging in wells: mechanical and chemical. In this research, mechanical way is applied. To improve and increase the performance of christmas trees, various types of filters are considered with their advantages and disadvantages according to previous experiences. Studies show that, for different type of wells different type of filters, separators etc. are used. Filters used to prevent sand particles are gravel filter, slot filter, perforated filter, wire well filter, well mesh filter, frame-rod filter, slot filter, support element filters and other filters which are considered in this research. According to the mesh principle, the filters which are a component of the ESP - are intended to prevent sand particles from entering the production stream by holding big particles and filtering the resulting liquid. To choose a filter with the best permeation rate and to stop particles larger than a specific size from penetrating, the size of the channels must be calculated. Modification and other movable factors are used to separate each group of filters. Keywords: Christmas tree (oil and gas), mechanical impurities, sand, filter, oil well, separators.

Al–7wt.-% Si–1wt.-% Fe alloy was solidified unidirectionally in the Crystallizer with High Rotating Magnetic Field (CHRMF). The diameter of sample was 8 mm and its length was 120 mm. The parameters of solidification were as follows: solid/liquid interface velocity ~0.082 mm/s, temperature gradient 7+/-1 K/mm, magnetic induction 0 and 150 mT, frequency of magnetic field 0 and 50 Hz. The structure solidified without rotating magnetic field (RMF) showed a homogeneous, columnar dendritic one. The structure solidified by using magnetic stirring showed a dual periodicity. On the one hand, the branches of the “Christmas tree”-like structure known from the earlier experiments contained Al+Si binary eutectic. On the other hand, bands with higher Fe- and Si-content formed in the sample, which were at a larger distance from each other than the branches of the “Christmas tree” structure. The developed microstructure was analyzed by SEM with EDS. The average Si- and Fe-concentrations were measured on the longitudinal section at given places along the length of sample. Furthermore the Si- and the Fe-concentrations close to the bands and among the bands as well as the composition of the compound phases were determined.

The study is intended to examine the survival of Aspergillus niger and its phosphate solubilizing ability when pelletedwith rock phosphate. An A. niger YD 17 obtainedfrom the Laboratory of Microbiology. Faculty of Agriculture, Gadjah MadaUniversity was used. The pellet was made by mixing rock phosphate (80%) with organic matter (J 3. 9% waste of tapioca. 6% rice bran, and 1% starch) and spore of A. niger. The experimental design was the Complete Randomized Design 5x4 with 3 replicatiOns. The first factor was sources of rock phosphate (Christmas Island. Jordan, China, Ciamis, and Madura). The secondfactor was the number ofinoculums i.e. control without inoculums, 107 • J(t and J(t cfu.g·'. The colony of A. niger that formed at medium of potatoes dextrose agar (PDA) and the amount of soluble phosphorus in the Pikovskaya liquid medium were parameters. Experimental results indicated that sources of rock phosphate and the number of inoculums itif1uence the A. niger survivability and its phosphorus solubilizing ability. Rock phosphate from Ciamis gave the best support for fungus survival and rock phosphate from Christmas Island was the best substrate for phosphate solubilization. The highest soluble phosphate was achieved by ul inoculums.

The subsea jumper has become an essential part of subsea production systems as a gas–liquid mixing pipeline connecting the pipeline end manifold (PLEM) to the Christmas tree. During oil and gas transportation, as a common flow pattern, the alternating flow characteristics of the slug flow easily cause pipeline vibration, resulting in pipeline instability or fatigue damage. The present study investigates experimentally and numerically the slug flow characteristics in the subsea M-shaped jumper and its induced vibrations of the jumper. The flow pattern evolution and slug characteristics of the inner slug flow under different gas–liquid velocities are obtained: the slug frequency and slug velocity, as well as the pressure fluctuation and vibration characteristics caused by the slug flow. The results show that the pressure fluctuations in the front and rear parts of the M-type jumper are obviously different. With the increase in the air–water mixing, the two characteristics, the slug frequency, and the slug velocity also increase. The gas velocity has a greater influence on the slug frequency than the liquid velocity. The slug length decreases as the slug frequency increases. Furthermore, numerical simulations under various experimental conditions are carried out. The results show that the simulation results of the pressure data, the slug characteristics, and the induced vibration amplitude are in good agreement with the experimental data.

Abstract Eleven treatments were applied to evaluate control of pine root collar weevil on heavily infested 8-12 ft Scotch pine Christmas trees. Individual treatments were applied to replicates after the duff below each tree was removed and bare ground was exposed. Liquid formulations were applied at the rate of 312 gal/acre (946 ml/tree) with a C02 compressed air sprayer with one 8004VS Teejet nozzle mounted on a 24 inch boom operating at 28 psi. Treatments were arranged in a randomized complete block design, replicated four times. The following conditions existed on 15 May: clear skies; air temperature, 90°F; water pH, 7.0; and RH, 39%. Each tree was dug and burlapped at the field site on 14 Nov, loaded into a rental truck, and returned to the laboratory. Each tree was thoroughly examined by removing all the bark from the root collar areas and lateral roots to record the presence of larvae. The soil ball was examined for the presence of larvae and adults.

Abstract AIM Endocrine therapy (ET) represents the first line treatment for patients with ER+, HER2- breast cancer, however disease progression is observed in many cases. PIK3CA and ESR1 are the most encountered mutated genes that have been associated with targeted molecular treatment, as well as with resistance to Endocrine Therapy. Liquid biopsy is a non-invasive procedure, that can provide “real-time” monitoring of disease progression and response to treatment. The aim of this study is to determine the mutation rate of ESR1 and PIK3CA genes in a selected cohort of 200 Greek breast cancer patients, using liquid biopsies and NGS technology. PATIENTS AND METHODS Liquid biopsies were collected from 200 ER-positive, HER2-negative metastatic breast cancer patients who have received at least one previous line of endocrine treatment. cfDNA was extracted using the QIAamp Circulating Nucleic Acid Kit (Qiagen). Library preparation was performed using Oncomine™ Breast cfDNA Research Assay (Thermofisher Scientific) and sequencing was carried out using Ion GeneStudio™ S5 System (Thermofisher Scientific). Ion Torrent Oncomine Knowledgebase Reporter was used in sequence analysis and interpretation of Copy number variations, SNPs, and indels. RESULTS Preliminary data of the first 49 examined samples demonstrated the prevalence of ESR1 and PIK3CA mutations in 20.4% (10/49) and 38.7% (19/49) of the cases respectively. The most frequently mutated codon in the ESR1 gene is the Y537, while in the PIK3CA gene, the H1047 codon is mainly altered. ESR1 and PIK3CA genes were co-mutated in 10.2% of the cases. Mutations in KRAS (6.1%) and TP53 (24%) were also detected. CONCLUSION More than 20% of the ER-positive, HER2-negative breast cancer patients with metastatic disease are eligible for targeted treatment with elacestrant. In addition, the high prevalence of mutations detected in our cohort indicates that liquid biopsy NGS panel testing can be used to monitor treatment response, track the development of resistance, and identify emerging genetic alterations that may guide treatment adjustments or the selection of alternative targeted therapies in breast cancer patients. REFERENCES Demir Cetinkaya B, Biray Avci C. Molecular perspective on targeted therapy in breast cancer: a review of current status. Med Oncol. 2022 Jul 14;39(10):149. doi: 10.1007/s12032-022-01749-1. PMID: 35834030; PMCID: PMC9281252. Liao H, Huang W, Pei W, Li H. Detection of ESR1 Mutations Based on Liquid Biopsy in Estrogen Receptor-Positive Metastatic Breast Cancer: Clinical Impacts and Prospects. Front Oncol. 2020 Dec 15;10:587671. doi: 10.3389/fonc.2020.587671. PMID: 33384956; PMCID: PMC7770162. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-elacestrant-er-positive-her2-negative-esr1-mutated-advanced-or-metastatic-breast-cancer Citation Format: Nikolaos Tsoulos, Angeliki Meintani, Georgios Kapetsis, Chrysiis Chatzigiannidou-Florou, Aikaterini Tsantikidi, Stella Maxouri, Eleni Thanou, Kalliopi Aggelaina, Vasiliki Metaxa-Mariatou, Georgios Tsaousis, Ioannis Natsiopoulos, Vasileios Venizelos, Christos Markopoulos, Flora Zagouri, Eleftherios Kampletsas, Eirini Karyda, Dimitrios Tryfonopoulos, Konstantinos Papazisis, Dimitrios Ziogas, Ilias Athanasiadis, Eirini Papadopoulou, Georgios Nasioulas. Liquid Biopsy Testing in a Greek Cohort of ER-positive, HER2-negative metastatic breast cancer patients [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-04-13.

On December 19, 1938, Otto Hahn wrote to Lise Meitner in Stockholm, asking her if she could propose some “fantastic explanation” for his and Fritz Strassmann’s finding of barium when bombarding uranium with neutrons. She and Otto Robert Frisch found such an explanation for what he called “nuclear fission” over the Christmas holidays, based on Gamow’s liquid-drop model of the nucleus. Bohr was astonished by this, but in 1936 he had speculated that the uranium nucleus would just explode. He, his son Erik, and his associate Léon Rosenfeld then took a ship to New York, arriving on January 16, 1939. Rosenfeld reported the discovery of fission that evening to the Princeton physics journal club. On January 26, physicists everywhere learned about this stunning discovery when Bohr and Fermi reported it at a conference in Washington, D.C. Physicists entered the New World of Nuclear Physics, taking Humanity with them.

Chapter 8 examines temperance and prohibition history within the Ottoman Empire and secular Turkey. Drinking and viticulture were widespread throughout the empire, though the trade was often in the hands of non-Muslims. The Ottoman liquor traffic even became integral to the European-run Ottoman Public Debt Administration. Mustafa Kemal Atatürk was among the drunkest leaders in world history, yet Atatürk and the secular Turkish government in Ankara embraced prohibitionism as a means of denying badly needed alcohol revenues to the Christians occupying their lands—most notably the British controlling Istanbul and the Greeks around Smyrna. Turkish prohibition expanded across Anatolia, as Atatürk liberated Turkey’s occupied territories. Only in 1924, with the end of foreign occupation, was the Kemalist prohibition rescinded, and replaced with a national alcohol monopoly, in which the financial benefits of the liquor trade would accrue to the Turkish state, not to foreigners.

Abstract Gas production can be enhanced by the unloading of liquid accumulated in the wellbore. Conventionally, it is addressed by dropping soap sticks into a gas well. The foamability of soap sticks tends to decrease in the presence of condensate. Alternativity, well can be kicked-off by using N2 lifting but it is an expensive method that involves coil tubing operation. In this paper, an innovative and simple method of unloading a condensate-bearing gas well using dry ice is described. Gas wells accumulated with liquid or condensate can be unloaded by displacing it with CO2 gas. It also helps to reduce hydrostatic pressure during kick-off well. Dry ice pellets can be inserted inside the wellbore, which can be settled down by gravity and CO2 gas formation inside the wellbore due to dry ice sublimation. The dry ice sublimation rate can be restricted by encapsulating it with self-degradable polymers that can be hydrolyzed inside the wellbore. Cylindrical dry ice pellets from the food industry having a half-inch diameter and a couple of inches long were used in this work. Dry ice is the solid form of CO2 having an expansion ratio of 1 to 554 for solid to gas at sublimation point −78.5 °C and atmospheric pressure. The density of dry ice is 1.562 gm/cm3. A series of lab experiments were conducted to show CO2 gas generation from dry ice in the water. After inserting a dry ice pellet into the water column, it settled down at the bottom and started releasing CO2 gas with a sudden expansion in volume. CO2 foam was also generated by inserting dry ice pallets with foaming agents inside the water column. The release of CO2 gas in the wellbore and foam generation can assist in decreasing hydrostatic pressure and lifting liquid inside the wellbore. At the well site, a simple modification is required to insert dry ice into the wellbore. The cylindrical chamber needs to be installed above the master value of the Christmas tree. This is described in the paper with the procedure to follow during the operation. A mathematical tool has been developed to estimate the amount of dry ice pallets required for a given well geometry. For 4.5 inch, 1000 ft long production tubing, 1000 kg dry ice can release 51.7 bbl of CO2 gas, which can generate a 495 psi increase in pressure. Well intervention operations are complex and expensive processes. It is preferred to use simpler, quicker, safer, and more cost-effective methodologies. The use of dry ice to unload gas well is simple, cheaper and an innovative solution. The release of CO2 gas from dry ice can offer additional benefits such as better and faster cleanup and the removal of condensate blockage in the near-wellbore area.

Abstract Objectives In wells which are producing on intermittent gas lift (IGL), the injected gas cannot sweep the entire liquid volume to the surface from the bottom of the tubing as there is continuously some fluid falling back in the tubing. The fallback can be described as the difference between the volume of the slug at the start of the gas injection and the volume of the actual produced slug at the surface. This fallback of liquid happens due to the fact that the gas has a tendency to flow through the liquid slug and letting the liquid to fall. The intensity of the liquid fallback increases more when there is increase in back pressure at wellhead. In order to minimize this liquid falling back in wells on intermittent gas lift, the sweeping pipe bend technology has been used in the various onshore fields operated by ONGC which has resulted in substantial gains and has been brought out in the paper. Process Gas break through and fallback are affected by three factors including the development of the gas bubble, the velocity of the slug flowing upward in the tubing, and wellhead restrictions caused due to presence of many 90-degree bends. To prevent gas breakthrough and to optimize the liquid fallback to minimum 5-7 % per 1000 feet of lift, it is recommended to maintain 1000 feet/min of minimum velocity of slug. Slower is the velocity of the slug which is moving up in the tubing, the longer time it takes for the gas to break through the liquid. At 1000 feet/min velocity, the wellhead restrictions can result in fallback losses due to breakthrough of gas in the well. In general, the flow path through the Christmas tree into the flowline is rather tortuous, moving first through a tee to the wing valve, then through other 90-degree ells before finally reaching the flowline. These restrictions further result in slowdown of the velocity of the slug thus resulting in more liquid to fallback and subsequently in significant production losses. Results In order to overcome the aforementioned problem and to reduce fallback in an intermittent gas lift well, sweeping pipe bend technology was considered and in the first phase implemented in 5 identified wells of different fields of ONGC Assets. With the help of sweeping pipe bend, the flow pattern becomes streamlined and number of 90-degree bends reduces or eliminates resulting in substantial reduction in the back pressure thus reducing the fall back. The implementation of the technology has resulted in an average liquid gain of 20.3% per well. Various guidelines for successful application of sweeping pipe bend have also been brought out in the paper. Additive Information 650 candidate wells operating on intermittent gas lift have been identified for the implementation of Sweeping Pipe Bends. As per the analysis, the implementation of Sweeping Pipe Bend is likely to result in a liquid gain of about 1000 m3/day from these wells.