Earl Hamilton: un gran historiador de la economía española.

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Numerical simulations of mixing conditions and aerosol dynamics in the CERN CLOUD chamber

To study the effect of galactic cosmic rays on aerosols and clouds, the Cosmics Leaving OUtdoor Droplets (CLOUD) project was established. Experiments are carried out at a 26.1 m3 tank at CERN (Switzerland). In the experiments, the effect of ionizing radiation on H2SO4 particle formation and growth is investigated. To evaluate the experimental configuration, the experiment was simulated using a coupled multidimensional computational fluid dynamics (CFD) – particle model. In the model the coupled fields of gas/vapor species, temperature, flow velocity and particle properties were computed to investigate mixing state and mixing times of the CLOUD tank's contents. Simulation results show that a 1-fan configuration, as used in first experiments, may not be sufficient to ensure a homogeneously mixed chamber. To mix the tank properly, two fans and sufficiently high fan speeds are necessary. The 1/e response times for instantaneous changes of wall temperature and saturation ratio were found to be in the order of few minutes. Particle nucleation and growth was also simulated and particle number size distribution properties of the freshly nucleated particles (particle number, mean size, standard deviation of the assumed log-normal distribution) were found to be distributed over the tank's volume similar to the gas species

Effect of dimethylamine on the gas phase sulfuric acid concentration measured by Chemical Ionization Mass Spectrometry

Sulfuric acid is widely recognized as a very important substance driving atmospheric aerosol nucleation. Based on quantum chemical calculations it has been suggested that the quantitative detection of gas phase sulfuric acid (H_2SO_4) by use of Chemical Ionization Mass Spectrometry (CIMS) could be biased in the presence of gas phase amines such as dimethylamine (DMA). An experiment (CLOUD7 campaign) was set up at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber to investigate the quantitative detection of H_2SO_4 in the presence of dimethylamine by CIMS at atmospherically relevant concentrations. For the first time in the CLOUD experiment, the monomer sulfuric acid concentration was measured by a CIMS and by two CI-APi-TOF (Chemical Ionization-Atmospheric Pressure interface-Time Of Flight) mass spectrometers. In addition, neutral sulfuric acid clusters were measured with the CI-APi-TOFs. The CLOUD7 measurements show that in the presence of dimethylamine (<5 to 70 pptv) the sulfuric acid monomer measured by the CIMS represents only a fraction of the total H_2SO_4, contained in the monomer and the clusters that is available for particle growth. Although it was found that the addition of dimethylamine dramatically changes the H_2SO_4 cluster distribution compared to binary (H_2SO_4-H_2O) conditions, the CIMS detection efficiency does not seem to depend substantially on whether an individual H_2SO_4 monomer is clustered with a DMA molecule. The experimental observations are supported by numerical simulations based on A Self-contained Atmospheric chemistry coDe coupled with a molecular process model (Sulfuric Acid Water NUCleation) operated in the kinetic limit

Performance of a corona ion source for measurement of sulfuric acid by chemical ionization mass spectrometry

The performance of an ion source based on corona discharge has been studied. This source is used for the detection of gaseous sulfuric acid by chemical ionization mass spectrometry (CIMS) through the reaction of NO−3 ions with H2SO4. The ion source is operated under atmospheric pressure and its design is similar to the one of a radioactive (americium-241) ion source which has been used previously. The results show that the detection limit for the corona ion source is sufficiently good for most applications. For an integration time of 1 min it is ~6×104 molecule cm−3 of H2SO4. In addition, only a small cross-sensitivity to SO2 has been observed for concentrations as high as 1 ppmv in the sample gas. This low sensitivity to SO2 is achieved even without the addition of an OH scavenger. When comparing the new corona ion source with the americium ion source for the same provided H2SO4 concentration, both ion sources yield almost identical values. These features make the corona ion source investigated here favorable over the more commonly used radioactive ion sources for most applications where H2SO4 is measured by CIMS

Etika Kristen dalam Pengelolaan Media Sosial Berbasis Information and Technology di Kalangan Remaja

The existence of information technology has become an important thing where as a tool that helps work in an organization, company, or institution. At this time, ethics in the world of information technology where Internet crime appears in general is a criminal act by hacking internet sites for personal purposes, while deviant behavior in internet use is such as cybersex and cyberaffair, sexting and pornography, cyberstalking and cyberbullying on the internet and also addicted to the internet. The method used in this research is qualitative research with a case study approach or often referred to as field research where qualitative research with a case study approach. The subjects in this study were teenagers. The subjects in this study were teenagers. Data collection was carried out by means of a literature study based on problems with the stages of collecting materials, reading materials, making notes, and managing notes obtained. According to the Christian ethical view, the human ability to study technology and information does not matter because technology can be used by humans in completing daily work, but on the other hand, technology and information become tools for humans to make mistakes in their lives. God to humans is intended so that humans build awareness from within themselves about the goodness and wisdom of God in every creation and innovation in technology and information, with this awareness humans will be able to use technological knowledge and information in a directed manner according to God's wishes and with Christian ethics

Experimental study on the influence of dimethylamine on the detection of gas phase sulfuric acid using chemical ionization mass spectrometry (CIMS)

Based on quantum chemistry calculations it has been suggested that the quantitative detection of gas phase sulfuric acid (H_2SO_4) by use of Chemical Ionization Mass Spectrometry (CIMS) could be biased in the presence of gas phase amines such as dimethylamine (DMA). An experiment was set up at the CLOUD aerosol chamber to test the quantitative detection of H_2SO_4 by CIMS by directly comparing the measured H_2SO_4 with and without DMA being present in the sample air. It was found that the H_2SO_4 cluster distribution changes but the CIMS detection efficiency is not strongly influenced

Identifikasi Perubahan Struktur Dna terhadap Pembentukan Sel Kanker Menggunakan Dekomposisi Graf

IDENTIFIKASI PERUBAHAN STRUKTUR DNA TERHADAP PEMBENTUKAN SEL KANKER MENGGUNAKAN DEKOMPOSISI GRAFABSTRAKKerusakan DNA adalah salah satu penyebab yang dapat mebuat sel normal bertumbuh menjadi sel kanker. Hal ini dikarenakan DNA yang rusak dapat menyebabkan mutasi di gen vital yang mengontrol pembelahan sel sampai terjadi pembelahan sel yang tidak terkendali dan memicu pertumbuhan sel kanker. Beberapa mutasi dibutuhkan untuk mengubah sel normal menjadi sel kanker. Dalam hal ini, teori dekomposisi graf digunakan untuk menganalisa proses terjadinya pertumbuhan sel kanker yang dimulai dari kerusakan DNA yang menyebabkan terjadinya mutasi gen. Dengan teori dekomposisi graf, sebuah graf bisa difaktorkan ke dalam beberapa subgraf. Pemfaktoran ini dapat digunakan untuk melihat pola Perubahan hubungan antar objek. Tujuan dari penelitian ini untuk mengidentifikasi struktur DNA terhadap pembentukan sek kanker dengan menggunakan dekomposisi graf. Yang diidenfikasi adalah mutasi delesi, addisi, dan substitusi dimana dari mutasi-mutasi ini dilihat hasil dekomposisi graf dan apakah dari ketiga mutasi ini dapat membentuk sel kanker.Kata Kunci : Struktur DNA, Sel Kanker, Dekomposisi Graf, Perfect Matching, Hamilton cycle IDENTIFICATION OF CHANGES OF DNA STRUCTURES ON CANCER CELL FORM USING GRAPH DECOMPOSITIONABSTRACTDNA damage is one of the causes that can make normal cells grow into cancer cells. This is because damaged DNA can cause mutations in vital genes that control cell division until uncontrolled cell division and trigger the growth of cancer cells. Some mutations are needed to convert normal cells into cancer cells. In this case theory of graph decomposition will be used to analyze the process of cancer cell growth that starts from the DNA damage that causes gene mutation. With the graph decomposition theory, a graph can be factored into several subgraphs. This factoring can be used to see patterns of relationship changes between objects. The purpose of this study was to identify the structure of DNA against the formation of cancer cells by using decomposition graph. What will be identified are the deletion mutations, additions, and substitutions from which these mutations are seen in the decomposition of the graph and whether these three mutations can form cancer cells

Job Diversity and Political Selection in China

Political elites rarely advance by moving up a single, well defined ladder; instead they accumulate experience across a variety of posts, creating defacto career tracks. Yet we still know surprisingly little about how those tracks pay off and why. We offer a systematic assessment of career pathways in the Chinese Communist Party (CCP) from 1982 to 2012. We assemble an annual panel of every full and alternate Central-Committee member, we map unique jobs into a directed transition network, and apply a SpringRank algorithm to derive a continuous leadership–status scale that spans all bureaucratic domains. This study takes a novel perspective on the selection of leaders in the Chinese Communist Party (CCP). We measure career tracks of full and alternate CCP Central Committee members investigate their role in political selection. We find that the career tracks corresponding to frequent rotations are associated with significantly higher probabilities of obtaining top leadership positions in the CCP despite the influence of patronage networks. By comparing the role of career tracks with that of personal connections, our findings speak to the research on institutional versus personalistic rules in non-democracies