In a photoionization experiment, several different ionization energies can be measured, depending on the degree of vibrational excitation of the cations. In general, the following two types of ionization energies are considered: 1.Adiabatic ionization energy, E Ia The energy corresponding to the transition M(X, v” = 0) + h n à M + (x, v’ = 0) + e - that is, the minimum energy required to eject an electron from a molecule in its ground vibrational state and transform it into a cation in the lowest vibrational level of an electronic state x of the cation. 2.Vertical ionization energy, E Iv The vertical ionization energy corresponds to the transition M(X, v” = 0) + h n à M + (x, v’ = n) + e - where, the value n of the vibrational quantum number v’ corresponds to the vibrational level whose wavefunction gives the largest overlap with the v” = 0 wavefunction. This is the most probable transition and usually corresponds to the vertical transition where the internuclear separations of the ionic state are similar to those of the ground state. It is clear that transitions to each of the ionic states x,a,b, c, … will have individual adiabatic and vertical ionization energies. 1垂直电离能计算： 优化分子构型，（同时也就得到分子能量了）使用这个构型减少电子计算离子的能量，离子减分子能量就是电离能了。 垂直 电离能的计算原理： 电离后的分子（实际上已是离子，但还没来得及发生结构松弛）的结构还没来得及改变时体系的能量与电离前分子的能量的差值。 2垂直电子亲和能： 在中性几何构型下阴离子和分子的能量差； AIP = E(阳离子，优化结构) - E(中性分子，优化结构) VIP = E(阳离子，优化中性分子结构) - E(中性分子，优化结构) ADE = E(中性分子，优化结构) - E(阴离子，优化结构) VDE = E(中性分子，优化阴离子结构) - E(阴离子，优化结构) http://w3.iams.sinica.edu.tw/lab/wbtzeng/ http://chemmat.hubu.edu.cn:82/Teach/jpkc/wulihuaxue/web/duomeiti/%E7%BB%93%E6%9E%84%E5%8C%96%E5%AD%A6%E8%AE%B2%E4%B9%89/new_page_22.htm
Optimization of vertical photobioreactors Thesis Submitted to The School of Engineering of the UNIVERSITY OF DAYTON In Partial Fulfillment of the Requirements for The Degree of Master of Science in Chemical Engineering 共140页。 摘要： This study focuses on optimizing the design of a photobioreactor to increase carbon dioxide sequestration by phototrophic microalgae. It is known that a significant amount of carbon dioxide emissions can be attributed to energy production processes and is expected to increase as global energy needs increase. The carbon dioxide emissions can be reduced by feeding carbon dioxide in the flue gas from power generation to an algal cultivation system. To increase carbon dioxide sequestration, it is imperative that an economical and robust photobioreactor that is capable of operating in any weather condition and location be designed. The focus of this study was to optimize vertical photobioreactors that are known to have a higher aerial productivity (higher biomass per unit area) and hence more efficient in sequestering carbon dioxide than the horizontal reactors. Horizontal tubular photobioreactor and vertical bubble column type units differ substantially in many ways; particularly with respect to the su***ce-to-volume ratio, the amount of gas in dispersion, the gas-liquid mass transfer characteristics, hydrodynamics, and internal irradiance levels. The effect of superficial velocity, temperature, carbon dioxide concentration, light irradiance, illuminated su***ce-to-volume ratio, pH, and gas holdup, and reactor geometry (diameter and height) were investigated with the algal specie Chlorella vulgaris in vertical bubble column reactors. Experiments were conducted on vertical photobioreactors of 2, 3, 4, 5, 6, 12, and 18 inch diameters of various heights (5, 8, and 10 feet) by changing the parameters that affect the algal density. In addition to the vertical bubble column configuration, algal densities in split and co-annular reactor designs were also investigated and found to be 1.334 and 1.842 g/L respectively. At the conditions studied, the 3 inch diameter vertical bubble column reactor produced the highest algal density (5.21 g/L) and the other reactors with 2, 4, 5, 6, 12 and 18 inch diameters reached densities of 0.938, 3.611, 3.296, 2.417, 1.665, 0.919 g/L respectively. The results show, that an increase in the ratio of the illuminated su***ce area to liquid volume in the reactor proportionately increases the biomass yields in vertical bubble column reactors and has the most effect on the final biomass yield in a vertical bubble column reactor. It was observed that increasing the reactor height from 5 feet to 10 feet had no effect on the biomass yields. Increasing the growth temperature from 20 to 35°C increased the biomass yields (20-27%) of Chlorella vulgaris. Increasing the CO2 concentration up to 9% in the air / CO2 flow increased the biomass yields and provided asufficient level of pCO2 while maintaining the pH level required for algal growth in the reactor geometries tested. This thesis stands out from others in presenting the data for larger operating volumes and geometries of vertical reactors (bubble column, split and co-annular). The growth data from a reactor with an 18 inch diameter and a height of 10 feet amounting to a reactor volume of 500 liters is among the first known publicly disclosed data reported for vertical bubble column reactors. 下载地址： http://www.pipipan.com/file/22165880
The sum of the squares of the first ten natural numbers is, 1 2 + 2 2 + ... + 10 2 = 385 The square of the sum of the first ten natural numbers is, (1 + 2 + ... + 10) 2 = 55 2 = 3025 Hence the difference between the sum of the squares of the first ten natural numbers and the square of the sum is 3025 385 = 2640. Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum. sumdiff - function(n) sum(c(1:n))^2-sum(c(1:n)^2) sumdiff(100) 25164150
标签: vertical
