...How has density functional theory improved for chemical applications? Discussion of some of the recent developments [0] Table of Contents Introduction3 Roots of DFT…………………………………………………………………………………………………………………………………………….3 Modern DFT4 Modifications6 Basis Sets6 Finding the EXC energy6 Hybrid Functionals8 Double Hybrid10 Strengths of DFT10 Challenges for DFT11 Current research12 Conclusions15 Introduction It has become an accepted fact that computational chemistry has become the partner to experimental chemistry. This is because computational experiments supplement real world experimental data very well. There are many systems in which there is no possible way of getting data about them, and so we must turn to computational methods. One example of this is looking at transition states, which in the real world may only exist for fractions of a second, however with the help of computational methods; we are able to investigate them easier, cheaper and quicker. There are many methods for computational chemistry experiments, however in this paper we will be focusing on how density functional theories (DFT) has impacted the chemistry community. The review will show how DFT started as an alternative to Schrodinger wave function methods, with simulated homogeneous electron gases, and moved on to be non-local, including other short and long range potentials and also combining empirical data to improve on the functionals. How DFT has its strengths and weaknesses and...
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...empec, Vol. 13, 1988, page 223-249 Nonparametric Estimation and Hypothesis Testing in Econometric Models By A. Ullah ~ Abstract: In this paper we systematically review and develop nonparametric estimation and testing techniques in the context of econometric models. The results are discussed under the settings of regression model and kernel estimation, although as indicated in the paper these results can go through for other econometric models and for the nearest neighbor estimation. A nontechnical survey of the asymptotic properties of kernel regression estimation is also presented. The technique described in the paper are useful for the empirical analysis of the economic relations whose true functional forms are usually unknown. 1 Introduction Consider an economic model y =R(x)+u where y is a dependent variable, x is a vector o f regressors, u is the disturbance and R(x) = E ( y l x ) . Often, in practice, the estimation o f the derivatives o f R(x)are o f interest. For example, the first derivative indicates the response coefficient (regression coefficient) o f y with respect to x, and the second derivauve indicates the curvature o f R(x). In the parametric econometrics the estimation o f these derivatives and testing 1 Aman Ullah, Department of Economics, University of Western Ontario, London, Ontario, N6A 5C2, Canada. I thank L Ahmad, A. Bera, A. Pagan, C. Robinson, A. Zellner, and the participants of the workshops at the Universities of Chicago...
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... complex systems of interacting objects. Detecting network communities in protein–protein interaction (PPI) as well as communitiesVgroups of objects that often correspond to func- product copurchasing networks have small overlaps and form tional modulesVis crucial to understanding social, technolog- many local cores. ical, and biological systems. Revealing communities allows for | Community detection; core–periphery structure; analysis of system properties that are invisible when consid- KEYWORDS ering only individual objects or the entire system, such as the identification of module boundaries and relationships or the ground-truth communities; networks classification of objects according to their functional roles. However, in networks where objects can simultaneously belong to multiple modules at once, the decomposition of a network into overlapping communities remains a challenge. Here we present a new paradigm for uncovering the modular structure of complex networks, based on a decomposition of a network into any combination of overlapping, nonoverlapping, and hierarchically organized communities. We demonstrate on a diverse set of networks coming from a wide range of domains that our approach leads to more accurate communities and improved identification of community boundaries. We also unify two fundamental organizing principles of complex networks: the modularity of communities and the commonly observed core–periphery structure...
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...Fourier Transform Infrared (FTIR) Spectroscopy Group 1 (Monday 1-5pm) Author Reshma Reji Outline Introduction Objective of the Experiment Theory * FTIR Spectroscopy * FTIR Spectrophotometer * Samples Experimental Physical properties of reagents used Solution Preparation Procedure Instrument settings Data 1. IR spectrum of Chloroform and D-chloroform 2. Rotational Spectrum of CO2 (Standard Resolution) 3. Rotational Spectrum of CO2 (High Resolution) 4. Carbonyl stretch in 2-butanone solutions (wavenumber vs. % T) 5. Carbonyl stretch in 2-butanone solutions (wavenumber Vs Absorbance) 6. Calibration curve of 2-butanone solutions (concentration vs. absorbance) * Calculations a. Preparation of solutions b. Concentration of the unknown c. Percent error of observed and theoretical ratios of CH, CD stretch frequencies Results and Conclusion References Objective The goal of the first part of the experiment was to study the effects of isotopes on bond stretching. In the second part of the experiment, the influence of instrument resolution on the rotational spectrum of carbon dioxide was studied. The purpose of the third part of the experiment was to create a calibration curve to find the unknown concentration of 2-butanone. Introduction Fourier Transform Infrared Spectroscopy (FTIR) is a very useful analytical technique used for qualitative and quantitative analysis of organic and inorganic...
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...First principles pressure dependent analysis on optical properties of cubic perovskite SrZrO3 Ghazanfar Nazir a, b, *, Afaq Ahmad b, Muhammad Farooq Khan a, Saad Tariq b a b Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747, South Korea Centre of Excellence in Solid State Physics, University of the Punjab, Lahore, Pakistan a r t i c l e i n f o a b s t r a c t Article history: Received 8 July 2015 Received in revised form 21 July 2015 Accepted 27 July 2015 Available online 31 July 2015 Here we report optical properties for cubic phase Strontium Zirconate (SrZrO3) at different pressure values (0, 40, 100, 250 and 350) GPa under density functional theory (DFT) using Perdew-Becke-Johnson (PBE-GGA) as exchange-correlation functional. In this article we first time report all the optical properties for SrZrO3. The real and imaginary dielectric functions has investigated along with reflectivity, energy loss function, optical absorption coefficient, optical conductivity, refractive index and extinction coefficient under hydrostatic pressure. We demonstrated the indirect and direct bandgap behavior of SrZrO3 at (0) GPa and (40, 100, 250 and 350) GPa respectively. In addition, static dielectric constant, Optical bandgap, Plasma frequency and Static refractive index has also been reported. We verified the Penn's model and showed the inverse relation between static dielectric constant and optical bandgap. Further, we proved...
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...Development of the social brain during adolescence Sarah-Jayne Blakemore Institute of Cognitive Neuroscience, University College London, London, UK Adolescence is usually defined as the period of psychological and social transition between childhood and adulthood. The beginning of adolescence, around the onset of puberty, is characterized by large hormonal and physical changes. The transition from childhood to adulthood is also characterized by psychological changes in terms of identity, self-consciousness, and cognitive flexibility. In the past decade, it has been demonstrated that various regions of the human brain undergo development during adolescence and beyond. Some of the brain regions that undergo particularly protracted development are involved in social cognitive function in adults. In the first section of this paper, I briefly describe evidence for a circumscribed network of brain regions involved in understanding other people. Next, I describe evidence that some of these brain regions undergo structural development during adolescence. Finally, I discuss recent studies that have investigated social cognitive development during adolescence. The first time Uta Frith made an impression on me was when I was 15. That year I was given a copy of her book Autism: Explaining the Enigma (U. Frith, 1989), which had recently been published. I knew nothing about autism and found Uta’s book captivating. It inspired me to write to its author and ask if I could...
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...February 2008 Abstract The experimental data for nanofluids in thermal-fluid systems have shown that the new fluids promise to become advanced heat transfer fluids in terms of thermal performance. While enhancing thermal characteristics, the solid–liquid mixtures present an unavoidable disadvantage in terms of pumping cost for economic operation of thermal-fluid systems. In addition, there is a lack of agreement between experimental data provided in the literature. The present work found that there would be no comprehensible design strategy in developing nanofluids. In this work, the Axiomatic Design (AD) theory is applied to systemize the design of nanofluids in order to bring its practical use forward. According to the Independence Axiom of the AD theory, the excessive couplings between the functional requirements and the parameters of a nanofluid system prevent from meeting the functional goals of the entire system. At a parametric level, the design of a nanofluid system is inherently coupled due to the characteristics of thermal-fluid system; the design parameters physically affect each other sharing sub-level parameters for nanoparticles with making a feedback loop. Even though parts of the nanofluids are naturally coupled, it is possible to reduce and/or eliminate the degree of coupling by help...
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...In the Harumi Apartments, we can see a return to the design of more traditional residential organizations with flexible spaces, only divided by sliding doors. These offered more possibilities than the functionalist plans orientated towards the existential minimum of a western nuclear family. Sliding screens could be closed to provide at least limited privacy, and opened or even removed for uninterrupted space. The ‘’traditional’’ features were functional, economical, and made the interior space more comfortable for those who used them. Even if the incorporation of the Japanese-style interiors into apartment buildings utilizing modern construction methods was not new in 1958, (buildings constructed in the late 1920 and 1930 by semipublic agency often incorporated tatami rooms) the scale on which the Harumi Apartments negotiated the apparent contradiction between high technology and premodern aesthetics was new. The strategy that wanted achieve Maekawa in these high-density housing, was a reasonable level of comfort within the constraints of public...
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...DEPARTMENT OF CHEMICAL ENGINEERING INDIAN INSTITUTE OF TECHNOLOGY KANPUR Che492-Unit Operations Laboratory II Experiment no. 5 Calandria Evaporator Instructors: Dr. Siddhartha Panda Dr. Deepak Kunzru Name of TA: Abir Ghosh Date of experiment: 23/9/2013 Date of submission: 30/9/2013 Group No: 2 Roll no. 10059 10062 10067 Name Akshay Bansal Akshit Gupta Aman Jain 1 Index Introduction Objective Theory and formulae Apparatus required Details required Observations and Calculations Sample calculation Results and Discussion Conclusion Precautions Sources of error Nomenclature Reference 3 4 4 6 6 6 8 8 8 9 9 9 9 2 Introduction The functional requirement of an evaporator is to vaporize a chemical liquid in order to achieve certain industrial benchmarks such as concentrating a solution, purification or retaining a number of useful solvents or to carry out crystallization on an industrial scale by achieving the limiting concentration. The fundamental working principle of an evaporator is characterized by heating the solution up to the boiling point of the solvent (in case of solid solute) or to the dew point of the solution (in case of liquid solute). The various types of industrially applicable evaporators are described as under: 1.) Direct heating evaporators-In these units, direct heating of the solution is carried out using solar energy or the heat energy of the gases which are brought to very high temperature using natural gas combustion. These are mainly used to extract salt...
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...Aging and dying is a major part of a person’s life, even though no one in this world knows quite how long they are going to live or when they are going to die. The process of aging is defined as “a progressive decline in the maximum functional level of individual cells, whole organs, and entire organisms”. As people get older, the body begins to slowly lose its degree of wellness, which includes physical and mental declines. Generally, most people reach their prime for physical capabilities during their twenties and thirties, but they can also reach it later on in life. Over the years, researchers have come up with many different theories regarding the causes of aging. Some of these theories include the wear and tear theory, the cellular theory, and the genetic mutation theory. The wear and tear theory, basically states that over a period time, a buildup of damage from internal and external factors eventually wears the body out and starts to it break down. The cellular theory, proposes that when we are born our cells are limited to only reproducing a certain amount of times before they die, then our organs begin to slowly rot away. Researchers promoting the genetic mutation theory believe that all the mutated cells in our body increases with age, so as people get older they tend to have more damage and problems within their cells. Most of the signs of aging are shown through the outward appearance of a person, such as wrinkles, baldness, gray hair, etc., and other signs can be...
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...humans, controls behavior, and supports sustainable development. Researchers often suggest that the design of residential and commercial space has pervasive effects on its inhabitants and is an important consideration in architectural design. Physical Structure and the Effects on Human Behavior Architecture as an art is a symbolic and intentional design that seems to reflect the psychology of its designers regardless of time, culture, and perhaps even gender. The space, form, and light are main elements generally incorporated purposely or unconsciously for aesthetic and practical reasons that give the creations meaning, purpose, and stability among an ever changing physical universe (Papow, 2000). Some people perceive architecture as functional and all designs are not esthetically pleasing, similar to the effect of any other art form. Architecture also can be an expression of cultural pride, societal passion, or self-esteem (Ayers, 2007). Research supports the idea that architectural design, structure of space, the number, spacing of windows, and the lighting affects people at some point. More over architectural design has “strong modifiable effects on social behavior, user’s mood, productivity, and to some extent, design features also affect health and wellbeing” (Ayers, 2007,...
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...presents various advantages, mainly higher density of storage and safety issues [2]. The research and the development of new hydrogen storage materials opened new possibilities for industrials. However, the major challenges in solid-state hydrogen storage, with particular reference to fuel cells and rechargeable batteries, are improved energy storage density, faster kinetics and better cycle life, by using readily available...
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...2 Expectations, Moments and Descriptive Statistics 3 Bivariate Distributions 4 Estimation 5 The Normal and Related Distributions and Interval Estimation 6 Hypothesis Testing These notes provide a summary of the lectures. They are not a complete account of the unit material. You should also consult the reading as given in the unit outline and the lectures. 1 10 19 26 35 43 Chapter 1 Some Basic Concepts 1.1 Probability It is customary to begin courses in statistics with a discussion of probability and then go on to derive certain propositions in probability theory. The problem with this approach is that probability is a difficult and potentially confusing subject. The foundations of probability theory are not well established. There are at least three different ways of thinking about probability. (a) (b) (c) Relative Frequency Subjective belief Mathematical theory The relative frequency idea of probability is the oldest concept and dates back to the eighteenth century (and probably before) when European mathematicians become interested in analysing games of chance. The basic idea is that the probability of an event occurring is the relative number of times the event occurs in a given number of trials. This introduces the important idea that the probability of the event A occurring lies between 0 and 1, or 0 ≤ P(A) ≤ 1 (1.1) It also means that the probability of a series of outcomes from a gambling game can be written as a simple...
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...Physical Science Chapter 14 1. There are two different elements in a water molecule. 2. Atoms heavier than hydrogen were made by nuclear fusion. 3. If we doubled the magnifying power of the most powerful optical microscope in the world, we would still not be able to see an atom. 4. Chemical compounds are made up of about 100 distinct elements. Atoms are the smallest subdivision of matter that still retains chemical properties of a substance. A quark is the smallest particle that exists. Electrons form atoms that in turn determine chemical properties of a substance. 5. The number of protons makes an element distinct. 6. Brownian motion has to do with random motions of atoms and molecules. 7. A quark is the smallest particle. 8. A molecule has structure, mass, and energy. 9. Solid matter is mostly empty space. Electrical forces prevent the solids from falling through one another. 10. Electrical forces determine the chemical properties of an atom. 11. The air in this room had no energy, no weight, and no mass. 12. Assuming all the atoms exhaled by Julius Caesar in his last dying breath are still in the atmosphere, then we probably breathe one of those atoms with each single breath. 13. Nuclei of atoms that make up a newborn baby were made in ancient stars. 14. The reason a granite block is mostly empty space is because the atoms in the granite are mostly empty space themselves. 15. Neutrons are electrically neutral. Protons are electrically positive. Electrons are eclectically...
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...Paper-I Principles of Geography Physical Geography i) Geomorphology : Factors controlling landform development; endogenetic and exogenetic forces; Origin and evolution of the earth’s crust; Fundamentals of geomagnetism; Physical conditions of the earth’s interior; Geosynclines; Continental drift; Isostasy; Plate tectonics; Recent views on mountain building; Vulcanicity; Earthquakes and Tsunamis; Concepts of geomorphic cycles and Landscape development ; Denudation chronology; Channel morphology; Erosion surfaces; Slope development ;Appl ied Geomorphology: Geohydrology, economic geology and environment ii) Climatology : Temperature and pressure belts of the world; Heat budget of the earth; Atmospheric circulation; atmospheric stability and instability. Planetary and local winds; Monsoons and jet streams; Air masses and fronto genesis, Temperate and tropical cyclones; Types and distribution of precipitation; Weather and Climate; Koppen’s, Thornthwaite’s and Trewartha’s classification of world climates; Hydrological cycle; Global climatic change and role and response of man in climatic changes, Applied climatology and Urban climate. iii) Oceanography : Bottom topography of the Atlantic, Indian and Pacific Oceans; Temperature and salinity of the oceans; Heat and salt budgets, Ocean deposits; Waves, currents and tides; Marine resources: biotic, mineral and energy resources; Coral reefs, coral bleaching; sealevel changes; law of the sea and marine pollution. iv) Biogeography :...
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