Development in The Sultanate of Oman during the rule of Sultan Qaboos

Celem pracy jest jest opis zmian zachodzących w Sułtanacie Omanu w latach 1970-2020. Omanem rządził wtedy Sułtan Kabus z dynastii Al Busaidów, panującej w tym kraju od 1744 roku. Zmarł w styczniu 2020 będąc najdłużej panującym monarchą na Bliskim Wschodzie. Główną teza uznaje, że za rządów Sułtana Kabusa, Oman rozwinął się gospodarczo i politycznie. Sułtan inwestował pieniądze pozyskiwane z ropy naftowej oraz dywersyfikował gospodarkę. Dzięki jego rządom Oman stał się nowoczesnym i bogatym państwem. Pracę rozpoczyna zarys historii Omanu i wojny w Zufarze, podczas której doszło do przejęcia władzy przez Kabusa. Opisana zostaje reforma systemu prawnego oraz sytuacja kobiet w Omanie. Drugi rozdział koncentruje się na trzech sektorach, które miały najbardziej znaczącą rolę w tworzeniu się współczesnej gospodarki Omanu: sektorze edukacyjnym, sektorze ropy i gazu oraz sektorze turystycznym. Ostatni rozdział opisuje politykę zagraniczną Sułtanatu. Przedstawione zostają relacje z innymi państwami Rady Współpracy Zatoki Perskiej, w tym postawa Omanu wobec kryzysu dyplomacji katarskiej w 2017 roku, relacje z Iranem i USA. Poddany zostaje analizie stosunek Sułtanatu do diaspory indyjskiej żyjącej w Omanie.The purpose of the work is to describe the changes that took place in the Sultanate of Oman in the years 1970-2020. At that time, Oman was ruled by the Sultan Qaboos of the The Al-Busaid dynasty, which had been in the country since 1744. He died in January 2020, being the longest reigning monarch in the Middle East. The main thesis recognizes that during the rule of Sultan Qaboos, Oman developed economically and politically. The Sultan invested money from oil and diversified the economy. Thanks to his rule, Oman became a modern and rich state. The work begins with an outline of the history of Oman and the war in Dhofar, during which Qaboos took over power. The reform of the legal system and the situation of women in Oman are presented. The second chapter focuses on three sectors that had the most significant role in the creation of the modern economy of Oman: the education sector, the oil and gas sector, and the tourism sector. The last chapter describes the foreign policy of the Sultanate. Relations with other countries of the Gulf Cooperation Council were presented, including Oman's attitude towards the Qatar diplomacy crisis in 2017, relations with Iran and the USA. The attitude of the Sultanate to the Indian diaspora living in Oman is being analyzed

Development of tourism as a way to diversify the economies of the Persian Gulf countries on the example of Oman

Celem pracy jest analiza sposobu dywersyfikacji gospodarki Omanu opartej na ropie naftowej, poprzez zbadanie rozwoju branży turystycznej w samym Omanie, jak i w sąsiednich krajach Półwyspu Arabskiego. W rozdziale pierwszym przedstawiono zarys historii rozwoju gospodarki w Zatoce Perskiej przed odkryciem ropy naftowej i w okresie późniejszym. W drugim rozdziale opisano plany i strategie rozwojowe, takie jak Wizja Oman 2040 oraz Strategia Turystyczna Omanu; zaprezentowano działalność organizacji OMRAN oraz założenia polityki i dyplomacji sułtana Qabusa oraz sułtana Haithama. W rozdziale trzecim zbadano czynniki rozwoju turystyki poprzez analizę potencjału warunków naturalnych oraz potencjału zasobów ludzkich w Omanie. Ostatni rozdział poświęcono problemom związanym z rozwojem branży turystycznej, takim jak przestrzeganie praw człowieka, kryzys gospodarczy (szczególnie wywołany pandemią koronawirusa) oraz problem ochrony środowiska naturalnego.Oman, Sułtanat Omanu, Zatoka Perska, Półwysep Arabski, Rada Współpracy Zatoki Perskiej, turystyka, dywersyfikacja gospodarcza, rozwój, gospodarka

Experimental investigations on electrorheological properties of lubricating oils containing ionic liquid. Part 2, Testing in dielectric spectroscopy

W artykule przedstawiono wyniki badań w tzw. spektroskopii dielektrycznej dwóch mieszanin oraz ich składników, tj. bazowych olejów izolujących i cieczy jonowych jako dodatków aktywnych elektrycznie. W pierwszej części badań [1] stwierdzono występowanie efektu ER w obu mieszaninach, gdy poddane były oddziaływaniu zewnętrznego stałego pola elektrycznego o natężeniu E ≤ 0,2 kV ⋅ mm⁻¹. Efekt elektroreologiczny był jednak krótkotrwały i niepowtarzalny na tej samej próbce cieczy, co sugerowało istotne zmiany jej struktury wewnętrznej. Stosując analizator impedancji HP 4192A, oceniono zmienność ich stałych dielektrycznych (ε) oraz rezystancji (R) i konduktywności (σ) w funkcji częstotliwości (f) stałego pola elektrycznego BIAS-u (DC), dla różnych wartości przyłożonego napięcia (U). Wykonano również testy powtarzane na tych samych próbkach mieszanin w celu zaobserwowania, jak pierwotnie przyłożone pole BIAS-u wpływa na dalsze zachowanie cieczy w polu elektrycznym. Na podstawie rezultatów badań uzyskano podstawę potwierdzenia symptomów zmian struktury wewnętrznej mieszanin, będących wynikiem działania zewnętrznego pola elektrycznego, prowadzących do zaniku efektu ER. W celu rozpoznania mechanizmu zaniku efektu ER zostaną przeprowadzone badania mikroskopowe in situ wytworzonych mieszanin poddanych działaniu zewnętrznego pola elektrycznego.The paper presents the results of investigations of two mixtures and their ingredients i.e. base insulating oils and ionic liquids as electrically active additives using, so called, dielectric spectroscopy. In part 1 of the study [1], the ER effect was found in both mixtures when they were subjected to an external constant electric field with the intensity of E ≤ 0.2 kV ⋅ mm⁻¹. However, the electrorheological effect was short-lived and unique on the same liquid sample, which suggested significant changes in its internal structure. Using the HP 4192 A Hewlett Packard impedance analyzer, the variability of their dielectric constans (ε), as well as the resistance (R) and the conductivity (σ), as a function of the frequency (f) of the constant electric field BIAS-u (DC) was assessed for different values of the applied voltage (U). Repeated tests were also carried out on the same samples of mixtures to observe how the originally applied BIAS field affects the further behavior of the liquid in the electric field. Based on the results of the research, the basis for confirming the symptoms of changes in the internal structure of mixtures, resulting, from the action of an external electric field, leading to the disappearance of the ER effect was obtained. In order to recognize the mechanism of disappearance of the ER effect, in situ microscopic tests of the prepared mixtures, subjected to an external electric field, will be carried out

Threshold voltage decrease in a thermotropic nematic liquid crystal doped with graphene oxide flakes

We report a threshold voltage decrease in a nematic liquid crystal compound, 4-cyano-4′-pentylbiphenyl (5CB), doped with graphene oxide (GO) flakes at a concentration of 0.05–0.3 wt %. The threshold voltage decrease was observed at the same concentration in electro-optic and dielectric spectroscopy measurements. The effect is related to the disrupted planar alignment due to the strong π–π stacking between the 5CB’s benzene rings and the graphene oxide’s structure. Additionally, we present the GO concentration dependence on the isotropic–nematic phase transition temperature, electric anisotropy, splay elastic constant, switch-on time, and switch-off time. The shape and dimensions of the GO flakes were studied using atomic force microscopy (AFM) and scanning electron microscopy (SEM). The influence of the GO concentration on the physical properties and switching process in the presence of the electric field was discussed

Dielectric Properties of Compounds Creating Dual-Frequency Nematic Liquid Crystals

In this paper we report how dielectric spectroscopy can help in creating of dual-frequency nematic liquid crystals. Dual-frequency nematic liquid crystals is new class of liquid crystal materials. Such mixture is usually formed by a combination of many components (even more than 10), which can be split into two groups: molecules having large transverse dipole moment and molecules with a large longitudinal dipole moment. The behavior of a base (parent) mixture, functional admixtures and final dual-frequency nematic liquid crystals mixture is investigated by dielectric spectroscopy in wide frequency (100 Hz-10 MHz) and temperature ranges. This allows us to find out why the dual-frequency liquid crystal has an important feature: positive and negative dielectric anisotropy at different frequencies. We present parameters of molecular motions around short (S-mode) and long (L-mode) molecular axes observed in investigated materials and discuss how the creation of final dual-frequency nematic liquid crystals mixture can modify molecular relaxations

The Influence of Microstructure and Lattice Strain on Tetragonality Factor and Dielectric Properties of Ferroelectric Ceramics BaTiO3BaTiO_3

This work is devoted to direct process of molten salt synthesis and studies on barium titanate ($BaTiO_3$, BT), belonging to ferroelectric crystal group type perovskite $BO_3$. This material thanks to its noncentrosymmetric, fully tetragonal structure possesses at room temperature (up to $T_{c}$ = 135°C) the spontaneous polarization. Due to this fact BT can be applied as piezoelectric material in electromechanical transducers, so as an excellent dielectric in multilayer capacitors and many other devices. With grain size reduction of BT ceramics to nanometric level it leads to permanent transformation into paraelectric state with minimized energy and to lose its specific features as a consequence, even at room temperature. In case of structural agent, means as tetragonality factor, it has a crucial influence on investigated material properties and it is referred in current paper. It is a row of complementary researching methods allows to confirm the presence of desired tetragonal BT phase in nano or micropowders obtained by means of molten salt synthesis route. For different temperature variants of synthesis X-ray diffraction analysis were undertaken and precise unit cells parameters both with tetragonality factor were determined using the Cohen method. Based on structural studies the lattice strains and crystallite sizes were estimated through the Williamson-Hall method. Using scanning electron microscopy the powders morphology and grain size distribution were done. Dielectric measurements of sintered BT ceramics were carried out to determine the Curie temperatures, dielectric permittivities and loss factors in prepared capacitors

Polar nematic phases with enantiotropic ferro- and antiferroelectric behaviour

The recent discovery of a new ferroelectric nematic (NF) liquid crystalline phase has become of utmost interest for the liquid crystal (LC) and the whole soft and condensed matter fields. Contrary to the previously known ferroelectric LC materials, whose ferroelectric characteristics were much weaker, new polar nematics exhibit properties comparable to solid ferroelectrics. This discovery brought about tremendous efforts to further explore compounds showing these phases, and fascinating physical properties have been reported. Herein, we present the first synthesized compounds with the enantiotropic ferro- (NF) and antiferroelectric (NX) nematic phases. The enantiotropic nature and an unprecedentedly broad temperature range of NF and NX phases are confirmed by various experimental techniques: polarized-light optical microscopy (POM) observations, different scanning calorimetry (DSC), dielectric spectroscopy, second harmonic generation (SHG), and molecular modeling. The presented achievements in designing achiral compounds that exhibit enantiotropic polar nematic phases with ferro- and antiferroelectric properties significantly contribute to the development of multicomponent mixtures with a broad temperature range of NF and NX phases down to room temperature. Furthermore, this accomplishment considerably enhances the general understanding of the structural correlations that promote polar nematic liquid crystal phases with high thermodynamic stability. Finally, this work may benefit various applications in photonic devices