COMPUTER SIMULATION: TRAFFIC-RELATED AIR POLLUTION AND THE TRAFFIC SIGNAL CYCLE TIME OPTIMIZATION

Emissions from motor vehicles, one of the most important air pollution sources in the city, is emerging as a growing problem in large-scale cities. The amounts of emissions are affected by the number of vehicles in traffic, vehicle technology, geometric and traffic conditions of highways and intersections, and environmental factors. Traffic flow is mostly interrupted at Intersections in local traffic, especially in city centers. Emissions of these points, where traffic behavior is changed and vehicles stop and go, are higher as compared to uninterrupted flows. In this study, current state emissions at 120 Intersection were determined by SIDRA INTERSECTION software. Then, new emissions are determined by the same software after improvement in signalization. As a result of the study, fuel consumption and pollutant emissions were calculated before and after improvement. As a result of observations at the intersection, current state fuel consumption was calculated as 1718.2, l/hour, and CO2, CO, HC, and NOX emissions were 40464.7, 3.821, 0.482, and 5.060 kg/hour respectively for the morning. After that current state fuel consumption was calculated as 1492.1, l/hour, and CO2, CO, HC, and NOX emissions were 3522, 3.116, 0.406, and 3.246 kg/hour respectively for the evening. It has been determined that there were significant differences between the current state and after improvement. Improvements in geometric conditions or signalization at intersections may result in a decrease in vehicle emissions and improve the air quality in cities

Modeling Of Terminology Database In Field Of Geodesy And Geographic Information System

Recently in Mongolia, many techniques and methods are being applied to the surveying and mapping fields along with the development and innovation of geodetic surveying technology, more new terminology are being used in those area. Despite of the origin of the terminology that came from or which language it’s being translated, those new words need to be interpreted by concerning the exact meaning of the word and what this word is actually referring to. However, in Mongolia, there’s no legal framework including regulation and standards of terminology and professional word translation. Consequently, a single term is being used with various meanings in many organizations, companies and so on. And also an ambiguous meaning of the term has been aroused and leads to wrong definition and idea. Due to this, lack of use of the terminology influences negatively on not only surveying and mapping field, but social areas as well. In order to solve this issue, study aims to create glossary database based on development of the terminology dictionary of geodesy and geographic information system through dynamic web design. In this study, many research methods have been carried out including, literature review based on the Dr. Damdinsuren (2013)’s “Glossary for Geodetic Terms”, textbooks and other materials of surveying and geospatial in English, Mongolian and Russian, as well as in print and online dictionaries, surveying questionnaire on usability and quality of professional terminology and dictionary and their applications within academia, professors, students, civil servants and private companies’ engineers, and SWOT analysis on printed and online dictionaries. Surveying questionnaire resulted that 20 per cent of 150 questionnaire use professional textbooks, which are printed in the Mongolian language, 45 per cent use Russian and 35 per cent use English sources. Glossary database on geodesy and geographic information system is established in three languages (Mongolian-English-Russian) using MySQL and PHP programming language. The users from geo-information industry will be able to develop and update the database based on the free and open source platform, particularly, online. This glossary database contains around 500 terminology including over 200 graphic illustrations. Frequent access of the terminology can be counted and web page includes links of relevant public organizations’ and universities’ web pages. So, the study results that this glossary database on geodesy and geographic information system could provide specific meaning of the term and how this term can be used depending on the specific field via dynamic web-page. And it allows and facilitates accessibility of database anywhere and anytime free of charge meaning that removes ambiguity and saves users\u27 precious time and money

Second-harmonic-generation of [(Se,Te)Cl3_{3}]+^{+} [GaCl4_{4}]–^{–} with aligned ionic tetrahedra

[SeCl$_{3}$][GaCl$_{4}$] (1) and [TeCl$_{3}$][GaCl$_{4}$] (2) are prepared via Lewis-acid–base reaction of SeCl$_{4}$ or TeCl$_{4}$ with GaCl$_{3}$ at 50 °C (1) and 140 °C (2) in quantitative yield. The ionic compounds contain pseudo-tetrahedral [SeCl$_{3}$]$^{+}$/[TeCl$_{3}$]$^{+}$ cations with a prominent stereochemically active electron lone pair at Se(IV)/Te(IV) as well as tetrahedral [GaCl$_{4}$]$^{–}$ anions. Both compounds crystallize in the polar chiral space group P1 with an unidirectional alignment of all tetrahedral building units. They can be considered as the first examples of a much larger group of ionic compounds [MX$_{3}$]$^{+}$[M′X$_{4}$]$^{–}$ (M, M′: metal or main-group element, X: halogen) showing nonlinear optical effects. Material characterization is performed by X-ray structure analysis based on single crystals and powder samples, thermogravimetry, optical spectroscopy, infrared and Raman spectroscopy. Second harmonic generation (SHG) is observed with intensities about 3-times stronger than for potassium dihydrogen phosphate (KDP) in the visible spectral regime with narrow-band-gap materials (2.8, 3.2 eV). Density functional theory calculations are employed to complement the experimental findings, interpret the Raman spectra, visualize the stereochemically active lone electron pair, and compute the SHG tensor

Residual strain investigation of a polycrystalline quartzite rock sample using time-of-flight neutron diffraction

In this work, we studied the residual micro lattice strain of an onyx sample, which is a micro- to the cryptocrystalline variety of the mineral quartz SiO$_2$. That the investigation has been carried out using in-situ stress experiments with the time-of-flight neutron diffraction method. The aim of the study is to investigate residual lattice strains and pressure directions in the sample using time-of-flight neutron diffraction, which is a powerful tool for the study of the residual strain behavior in bulk materials, like geological rock samples containing large grains. The residual strain was detected in different sample directions turning the sample in steps of 30° by 180° around the cylindrical z-axis. These experiments have been performed at the time-of-flight neutron strain diffractometer EPSILON, situated on the pulsed neutron source IBR-2M of the Joint Institute for Nuclear Research in Dubna, Russia. The results of this study will provide insights into the compressional and tensional residual strain of the crystallographic lattice planes, and will have implications for our understanding of the tectonic history of this region. These different strains are arranged in the sample by a sinusoidal distribution in radial directions

Order and Disorder in Mixed (Si, P)–N Networks Sr2SiP2N6:Eu2+ and Sr5Si2P6N16:Eu2+

In the field of nitride phosphors, which are crucial for phosphor-converted light-emitting diodes, mixed tetrahedral networks hold a significant position. With respect to the wide range of compositions, the largely unexplored (Si, P)–N networks are investigated as potential host structures. In this work, two highly condensed structures, namely Sr2SiP2N6 and Sr5Si2P6N16 are reported to address the challenges that arise from the similarities of the network-forming cations Si4+ and P5+ in terms of charge, ionic radius, and atomic scattering factor, a multistep workflow is employed to elucidate their structure. Using single-crystal X-ray diffraction, energy-dispersive X-ray spectroscopy (EDX), atomic-resolution scanning transmission electron microscopy (STEM)-EDX maps, and straightforward crystallographic calculations, it is found that Sr2SiP2N6 is the first ordered, and Sr5Si2P6N16 the first disordered, anionic tetrahedral (Si, P)–N network. After doping with Eu2+, Sr2SiP2N6:Eu2+ shows narrow cyan emission (λmax = 506 nm, fwhm = 60 nm/2311 cm−1), while for Sr5Si2P6N16:Eu2+ a broad emission with three maxima at 534, 662, and 745 nm upon irradiation with ultraviolet light is observed. An assignment of Sr sites as probable positions for Eu2+ and their relation to the emission bands of Sr5Si2P6N16:Eu2+ is discussed

18-Crown-6 Coordinated Metal Halides with Bright Luminescence and Nonlinear Optical Effects

The crown-ether coordination compounds ZnX$_{2}$(18-crown-6), EuX$_{2}$(18-crown-6) (X: Cl, Br, I), MnI$_{2}$(18-crown-6), Mn$_{3}$Cl$_{6}$(18-crown-6)2, Mn$_{3}$I$_{6}$(18-crown-6)$_{2}$, and Mn$_{2}$I$_{4}$(18-crown-6) are obtained by ionic-liquid-based synthesis. Whereas MX$_{2}$(18-crown-6) (M: Zn, Eu) show conventional structural motives, Mn$_{3}$Cl$_{6}$(18-crown-6)$_{2}$, Mn$_{3}$I$_{6}$(18-crown-6)$_{2}$, and Mn$_{2}$I$_{4}$(18-crown-6) exhibit unusual single MnX$_{4}$ tetrahedra coordinated to the crown-ether complex. Surprisingly, some compounds show outstanding photoluminescence. Thus, rare Zn$^{2+}$-based luminescence is observed and unexpectedly efficient for ZnI$_{2}$(18-crown-6) with a quantum yield of 54%. Unprecedented quantum yields are also observed for Mn$_{3}$I$_{6}$(18-crown-6)$_{2}$, EuBr$_{2}$(18-crown-6), and EuI$_{2}$(18-crown-6) with values of 98, 72, and 82%, respectively, which can be rationalized based on the specific structural features. Most remarkable, however, is Mn$_{2}$I$_{4}$(18-crown-6). Its specific structural features with finite sensitizer–activator couples result in an extremely strong emission with an outstanding quantum yield of 100%. Consistent with its structural features, moreover, anisotropic angle-dependent emission under polarized light and nonlinear optical (NLO) effects occur, including second-harmonic generation (SHG). The title compounds and their optical properties are characterized by single-crystal structure analysis, X-ray powder diffraction, chemical analysis, density functional theory (DFT) calculations, and advanced spectroscopic methods