FABRICATION AND CHARACTERIZATION OF ORGANIC-INORGANIC HYBRID PEROVSKITE SOLAR CELLS

Solar energy as the most abundant source of energy is clean, non-pollutant, and completely renewable, which provides energy security, independence, and reliability. Organic-inorganic hybrid perovskite solar cells (PSCs) revolutionized the photovoltaics field not only by showing high efficiency of above 22% in just a few years but also by providing cheap and facile fabrication methods. In this dissertation, fabrication of PSCs in both ambient air conditions and environmentally controlled N2-filled glove-box are studied. Several characterization methods such as SEM, XRD, EDS, Profilometry, four-point probe measurement, EQE, and current-voltage measurements were employed to examine the quality of thin films and the performance of the PSCs. A few issues with the use of equipment for the fabrication of thin films are addressed, and the solutions are provided. It is suggested to fabricate PSCs in ambient air conditions entirely, to reduce the production cost. So, in this part, the preparation of the solutions, the fabrication of thin films, and the storage of materials were performed in ambient air conditions regardless of their humidity sensitivity. Thus, for the first part, the fabrication of PSCs in ambient air conditions with relative humidity above ~36% with and without moisture sensitive material, i.e., Li-TFSI are provided. Perovskite materials including MAPbI3 and mixed cation MAyFA(1-y)PbIxBr(1-x) compositions are investigated. Many solution-process parameters such as the spin-coating speed for deposition of the hole transporting layer (HTL), preparation of the HTL solution, impact of air and light on the HTL conductivity, and the effect of repetitive measurement of PSCs are investigated. The results show that the higher spin speed of PbI2 is critical for high-quality PbI2 film formation. The author also found that exposure of samples to air and light are both crucial for fabrication of solar cells with larger current density and better fill factor. The aging characteristics of the PSCs in air and vacuum environments are also investigated. Each performance parameter of air-stored samples shows a drastic change compared with that of the vacuum-stored samples, and both moisture and oxygen in air are found to influence the PSCs performances. These results are essential towards the fabrication of low-cost, high-efficiency PSCs in ambient air conditions. In the second part, the research is focused on the fabrication of high-efficiency PSCs using the glove-box. Both single-step and two-step spin-coating methods with perovskite precursors such as MAyFA(1-y)PbIxBr(1-x) and Cesium-doped mixed cation perovskite with a final formula of Cs0.07MA0.1581FA0.7719Pb1I2.49Br0.51 were considered. The effect of several materials and process parameters on the performance of PSCs are investigated. A new solution which consists of titanium dioxide (TiO2), hydrochloric acid (HCl), and anhydrous ethanol is introduced and optimized for fabrication of quick, pinhole-free, and efficient hole-blocking layer using the spin-coating method. Highly reproducible PSCs with an average power conversion efficiency (PCE) of 15.4% are fabricated using this solution by spin-coating method compared to the conventional solution utilizing both spin-coating with an average PCE of 10.6% and spray pyrolysis with an average PCE of 13.78%. Moreover, a thin layer of silver is introduced as an interlayer between the HTL and the back contact. Interestingly, it improved the current density and, finally the PCEs of devices by improving the adhesion of the back electrode onto the organic HTL and increasing the light reflection in the PSC. Finally, a highly reproducible fabrication procedure for cesium-doped PSCs using the anti-solvent method with an average PCE of 16.5%, and a maximum PCE of ~17.5% is provided

Government Wilayah Al-Faqih in Iran and Contemporary Global Challenges

Today, despite all pressures and sanctions of the global politic, the Islamic Revolution of Iran has its own place in the hearts of freedom seeking people all over the world and every day, its progress and grandeur is improving. Therefore, progress of Islamic Iran during the last four decades is not something covered to all people and declaring these challenges across the society will lead to hopefulness and increase of resistance of people against these plots. Discussing the challenges of the Islamic Revolution and picturing them is a great and basic necessity of the present time. Therefore, this paper tends to clarify the most important challenges of the Islamic Revolution of Iran, from the very beginning to the present time, under the Islamic government based upon the Government of Wilayah Al-Faqih. On the contrary of propaganda of the enemies of the Islamic government, Islamic Revolution of Iran has faced great and eye catching progress in political, cultural, economic, scientific, technological, military, and intelligence areas despite all obstacles and limited facilities and now has reached a high position throughout the region and the world

Endogenous resistance to insect pests in alfalfa: engineering for enhanced resistance

Alfalfa (Medicago sativa) is a valuable forage crop grown throughout the World. While the crop is resistant to attack by many insect pests, it is subject to potentially severe losses through the action of several specific pests, which are adapted to alfalfa as a host. The most economically damaging of these pests is the alfalfa weevil, Hypera postica. This thesis investigates the endogenous defences of alfalfa against insects, which are responsible for its resistance to non-pest species, and develops a strategy for increasing the resistance of alfalfa towards pest species, specifically alfalfa weevil. The role of saponins in the resistance of alfalfa towards non-pest species has been investigated by using successive insect bioassays, carried out with extracts, mixtures of compounds, and purified compounds, to identify which compounds present in alfalfa tissues are responsible for toxicity towards insects. Crude saponin extracts, in 80% methanol, from alfalfa seedling tissues were bioassayed against the cowpea seed weevil, Callosobruchus maculatus. Both extracts from shoot and root tissues caused larval mortality and delayed development when incorporated into an artificial diet at levels comparable to those found in alfalfa, but lower levels of root saponin extracts showed probiotic effects, whereas lower levels of shoot saponins were still toxic. Hydrolysis of the saponins present in these extracts decreased their toxicity. Purified saponin mixtures were prepared by butanol partition and ether precipitation, and were bioassayed against potato aphid (Aulacorthum solani) in a liquid artificial diet, which allowed quantitative effects to be accurately assayed. Shoot saponins showed a concentration-dependent toxic effect, decreasing survival over an initial 5 day period, decreasing growth, and inhibiting fecundity (measured by nymph production) in these insects. Alfalfa root saponins showed no deleterious effects below a threshold level, but caused complete mortality above this level. The alfalfa saponin mixtures were separated into fractions by chromatography on a reverse phase column. Bioassays showed that the toxicity towards potato was associated only with fractions containing saponins, and that fractions containing a component identified as soyasaponin I were more toxic to the aphids than others. Finally, two saponins purified from alfalfa, soyasaponin I and medicoside A, were assayed. These assays showed that soyasaponin was consistently more toxic in effects on mortality, growth and fecundity. It was concluded that alfalfa saponins, and in particular soyasaponin I, were major factors in the resistance of alfalfa towards potato aphid, and other insects. A saponin mixture from another species, sugar beet {Beta vulgaris) was also toxic to aphids, supporting the view that saponins have a general role in resistance to insects. Inhibition of insect digestive proteolysis by expression of a foreign protein protease inhibitor was selected as a strategy to protect transgenic alfalfa against alfalfa weevil. The major protease activity in larvae of this msect was shown to be due to cysteine proteases, which could be inhibited by cystatins. Rice cystatin was produced in large quantity using a recombinant protein expression system in E. coli for use in a "proving" experiment. Incorporation of the rice cystatin into an alfalfa weevil larvae artificial diet decreased survival, showing that this approach was feasible

Antenna and system design for controlled delivery of microwave thermal ablation

Doctor of PhilosophyDepartment of Electrical and Computer EngineeringPunit PrakashMicrowave ablation is an established minimally invasive modality for thermal ablation of unresectable tumors and other diseases. The goal of a microwave ablation procedure is to deliver microwave power in a manner localized to the targeted tissue, with the objective of raising the target tissue to ablative temperatures (~60 °C). Engineering efforts in microwave applicator design have largely been focused on the design of microwave antennas that yield large, near-spherical ablation zones, and can fit within rigid needles or flexible catheters. These efforts have led to significant progress in the development and clinical application of microwave ablation systems, particularly for treating tumors in the liver and other highly vascular organs. However, currently available applicator designs are ill-suited to treating targets of diverse shapes and sizes. Furthermore, there are a lack of non-imaging-based techniques for monitoring the transient progression of the ablation zone as a means for providing feedback to the physician. This dissertation presents the design, implementation, and experimental evaluation of microwave ablation antennas for site-specific therapeutic applications with these issues in mind. A deployable 915 MHz loop antenna is presented, providing a minimally-invasive approach for thermal ablation of the endometrial lining of the uterus for treatment of heavy menstrual bleeding. The antenna incorporates a radiating loop, which can be deployed to adjustable shapes within the uterine cavity, and a passive element, to enable thermal ablation, to 5.7–9.6 mm depth, of uterine cavities ranging in size from 4–6.5 cm in length and 2.5–4.5 cm in width. Electromagnetic–bioheat transfer simulations were employed for design optimization of the antennas, and proof-of-concept applicators were fabricated and extensively evaluated in ex vivo tissue. Finally, feasibility of using the broadband antenna reflection coefficient for monitoring the ablation progress during the course of ablation was evaluated. Experimental studies demonstrated a shift in antenna resonant frequency of 50 MHz correlated with complete ablation. For treatment of 1–2 cm spherical targets, water-cooled monopole antennas operating at 2.45 and 5.8 GHz were designed and experimentally evaluated in ex vivo tissue. The technical feasibility of using these applicators for treating 1–2 cm diameter benign adrenal adenomas was demonstrated. These studies demonstrated the potential of using minimally-invasive microwave ablation applicators for treatment of hypertension caused by benign aldosterone producing adenomas. Since tissue dielectric properties have been observed to change substantially at elevated temperatures, knowledge of the temperature-dependence of tissue dielectric properties may provide a means for estimating treatment state from changes in antenna reflection coefficient during a procedure. The broadband dielectric properties of bovine liver, an established tissue for experimental characterization of microwave ablation applicators, were measured from room temperature to ablative temperatures. The measured dielectric data were fit to a parametric model using piecewise linear functions, providing a means for readily incorporating these data into computational models. These data represent the first report of changes in broadband dielectric properties of liver tissue at ablative temperatures and should help enable additional studies in ablation system development

Combined effects of fungal β-glucan and Zataria multiflora essential oil on phagocytosis in Balb/C mice

Introduction: Natural substances have been used since ancient times for treatment of a range of diseases and have represented stimulatory effects on the function of innate immunity. The purposes of this study were to prepare β-glucan from S. cerevisiae and to assess the efficacy of purified β-glucan, Zataria multiflora (Z. multiflora) essential oil and their complex on phagocytosis in Balb/c mice.Methods: β-glucan was purified during three stages including alkaline-acid treatment (S1), DEAE sephacel chromatography (S2) and con-A sepharose chromatography (S3). Z. multiflora essential oil was extracted by water-distillation using Clevenger-type apparatus. The chemical composition of Z. multiflora essential oil was analyzed by a GC/MS system. β-glucan (15 mg/kg), Z. multiflora essential oil (100 mg/kg) and their complex (the same doses) were injected into Balb/c mice intraperitoneally (IP). The blood samples were collected at days 4 and 7 after injection and phagocytic activity was assayed by chemiluminescence method.Results: The results showed that the ratios of mannan to β-glucan were 70.3 to 29.7 for S1, 71.9 to 28.1 for S2 and zero to 100 for S3 (purified β-glucan). The major components of Z. multiflora were carvacrol (61) and thymol (25). Phagocytosis index means exhibited significant increases at day 4 (246, 165 and 367) and day 7 (242, 235 and 309) in mice treated with purified β-glucan, Z. multiflora essence, and their complex when compared to control mice, respectively (P < 0.05).Conclusion: The results suggest that the complex of β-glucan and Z. multiflora oil might be used to immunize individuals as prophylactic and/or therapeutic adjuvant in immunocompromised subjects

Zataria multiflora Boiss.: A review study on chemical composition, anti-fungal and anti-mycotoxin activities, and ultrastructural changes

Introduction: Zataria multiflora is a valuable medicinal plant from Lamiaceae family with various pharmacological and therapeutic properties. In this article we reviewed the various aspects of Z. multiflora properties including botanical characteristics, chemical composition, anti-fungal and anti-mycotoxin activity and fungal ultrastructural changes.Methods: Google Scholar, PubMed, EBSCO, Directory of open access journals (DOAJ), EMBASE, and Web of Science were searched using the keywords Z. multiflora and pathogenic and toxigenic fungi.Results: The essential oil (EO) of Z. multiflora is frequently used in pharmaceutical industries. Thymol and carvacrol are the most important active components of Z. multiflora that are used for the treatment of a wide variety of diseases such as candidiasis and dermatophytosis. Aflatoxin production inhibitory effect of Z. multiflora EO was at the transcription level and this herb may cause reduction in aflatoxin biosynthesis. Ultrastructural changes showed that the main sites of action of EO were the plasma membrane and cell wall of fungi.Conclusion: Zataria multiflora has the potential to be considered as a new natural drug for the treatment of some fungal infections. Morphological and structural changes may be one of the mechanisms involved in growth inhibition of the fungi and reducing aflatoxin production by Z. multiflora EO

An Overview of the European Court of Human Rights

Based on the European Convention on Human Rights, in 1959 the European Court of Human Rights was established in order to deal with applications against member states (High Contracting Parties) about the violation of the rights and freedoms contained in the Convention including: the right to life, the prohibition of slavery, servitude and forced labor, the right to liberty and security, the right to begin entitled to a fair trial, the right to freedom of expression, the right to respect for one’s private and family life, the right to freedom of thought, conscience and religion and so on. Subsequently, various Protocols were annexed to this Convention including the Protocol 11 of European Convention on Human Rights. Through eliminating former two-steps system consisting of European Commission of Human Rights (ECHR) and the European Court of Human Rights, the system became one-step. A fundamental revision was made in the structure and the proceedings system of the Court. In this article, along with the introduction and the consideration of the structure and the judicial procedure of the new Court, we proceed to examine the Court jurisdiction and how the decisions are made

Inhibitory effect of plant essential oils on Malassezia strains from Iranian dermatitis patients

Introduction: The genus Malassezia is an important skin resident of human. The present study aimed to analyze in vitro activity of the essential oils of Lavandula stoechas, Cuminum cyminum and Artemisia sieberi against clinical strains of Malassezia species. Methods: A total of 47 Malassezia strains, including Malassezia furfur, Malassezia globosa and Malassezia obtuse, were used in this study. A disk diffusion technique was selected for testing the susceptibility of Malassezia strains to the essential oils. Results: All the essential oils showed in vitro activity against Malassezia strains, with M. furfur and M. obtusa being the highest and lowest susceptible of the strains, respectively. The highest antifungal activity was associated with the essential oil of C. cyminum (mean ± SD: 50.0 ± 0.0 mm), followed by L. stoechas (mean ± SD: 46.8 ± 3.1 mm) and A. sieberi (mean ± SD: 36.9 ± 5.7 mm). The inhibition zone ranges were 12.5 to 15.6 mm (mean ± SD: 14.4 ± 1.6 mm) for ketoconazole and 11.6 to 13.3 mm (mean ± SD: 12.4 ± 0.9 mm) for fluconazole. Although all the antifungal drugs were found to possess good antifungal activities against Malassezia strains, their effects were lower than the activities shown by the essential oils tested (P<0.05). Conclusion: These results indicated that the essential oils tested, especially the one from C. cyminum, inhibited the growth of clinical strains of Malassezia, implying its potential use in the treatment of Malassezia infections. This indicates that this plant may be useful in preparation of new drugs

EEG spectral power alternation & learning disability in rats exposure to lead through prenatal developing age

Introduction: Lead intoxication in children has been associated with neurodevelopment disabilities that may result in motor and cognitive impairment. The aim of the present study is to evaluate in long term effects of prenatal exposure to low-level Pb2+ on learning, memory and EEG. Materials & Methods: Rat pregnant were exposed to distilled water or 0.05, 0.1, 0.2 % of Pb-acetate in the drinking water during of pregnancy. Behavioral analysis was carried out in male offspring by using one way active avoidance. The numbers of electric shock was detected as an index of learning and memory of rats. At 60 days of age (active avoidance learning) and at 90 days of age (memory) behavioral assessment was measured. Then the rats were implanted with electrodes in sensorimotor regain. After a recovery period, EEG was also recorded. Findings: Lead acetate was no affected on learning but dose of 0.1% which was affected on memory of rats (No. of shocks 5.185 ± 0.98%) compared to the control (No. of shocks 1.667 ± 0.62%). This finding also showed that lead acetate (p<0.05) only decreases of memory ability. Except an increase in the delta waves, there was no any statistical signifiucant on EEG spectral power between test and control groups. Conclusion: In this research the lead acetate was no affected on EEG. The results showed that using dose of 0.1% lead acetate was affected on behavior and decrease of memory ability of tested rats