scholarly journals Rapid growth of anthropogenic organic nanoparticles greatly alters cloud life cycle in the Amazon rainforest

2022 ◽  
Vol 8 (2) ◽  
Author(s):  
Rahul A. Zaveri ◽  
Jian Wang ◽  
Jiwen Fan ◽  
Yuwei Zhang ◽  
John E. Shilling ◽  
...  
Keyword(s):  
Life Cycle ◽  
Rapid Growth ◽  
Oxidation Products ◽  
Amazon Rainforest ◽  
Organic Nanoparticles

Oxidation products of natural hydrocarbons rapidly grow pollution nanoparticles to sizes large enough to alter clouds.

scholarly journals Biomass burning emission disturbances of isoprene oxidation in a tropical forest

2018 ◽  
Vol 18 (17) ◽  
pp. 12715-12734 ◽  
Author(s):  
Fernando Santos ◽  
Karla Longo ◽  
Alex Guenther ◽  
Saewung Kim ◽  
Dasa Gu ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Biomass Burning ◽  
Oxidative Capacity ◽  
Oxidation Products ◽  
Amazon Rainforest ◽  
Amazon Forest ◽  
Oxidation Reactions ◽  
Smoke Plumes ◽  
Isoprene Oxidation ◽  
The Impact

Abstract. We present a characterization of the chemical composition of the atmosphere of the Brazilian Amazon rainforest based on trace gas measurements carried out during the South AMerican Biomass Burning Analysis (SAMBBA) airborne experiment in September 2012. We analyzed the observations of primary biomass burning emission tracers, i.e., carbon monoxide (CO), nitrogen oxides (NOx), ozone (O3), isoprene, and its main oxidation products, methyl vinyl ketone (MVK), methacrolein (MACR), and isoprene hydroxy hydroperoxide (ISOPOOH). The focus of SAMBBA was primarily on biomass burning emissions, but there were also several flights in areas of the Amazon forest not directly affected by biomass burning, revealing a background with a signature of biomass burning in the chemical composition due to long-range transport of biomass burning tracers from both Africa and the eastern part of Amazonia. We used the [MVK + MACR + ISOPOOH] ∕ [isoprene] ratio and the hydroxyl radical (OH) indirect calculation to assess the oxidative capacity of the Amazon forest atmosphere. We compared the background regions (CO < 150 ppbv), fresh and aged smoke plumes classified according to their photochemical age ([O3] ∕ [CO]), to evaluate the impact of biomass burning emissions on the oxidative capacity of the Amazon forest atmosphere. We observed that biomass burning emissions disturb the isoprene oxidation reactions, especially for fresh plumes ([MVK + MACR + ISOPOOH] ∕ [isoprene] =  7) downwind. The oxidation of isoprene is higher in fresh smoke plumes at lower altitudes (∼ 500 m) than in aged smoke plumes, anticipating near the surface a complex chain of oxidation reactions which may be related to secondary organic aerosol (SOA) formation. We proposed a refinement of the OH calculation based on the sequential reaction model, which considers vertical and horizontal transport for both biomass burning regimes and background environment. Our approach for the [OH] estimation resulted in values on the same order of magnitude of a recent observation in the Amazon rainforest [OH] ≅ 106 (molecules cm−3). During the fresh plume regime, the vertical profile of [OH] and the [MVK + MACR + ISOPOOH] ∕ [isoprene] ratio showed evidence of an increase in the oxidizing power in the transition from planetary boundary layer to cloud layer (1000–1500 m). These high values of [OH] (1.5 × 106 molecules cm−3) and [MVK + MACR + ISOPOOH] ∕ [isoprene] (7.5) indicate a significant change above and inside the cloud decks due to cloud edge effects on photolysis rates, which have a major impact on OH production rates.

LARVAL GROWTH AND DEVELOPMENT OF ARGIA VIVIDA (ODONATA: COENAGRIONIDAE) IN WARM SULPHUR POOLS AT BANFF, ALBERTA

1977 ◽  
Vol 109 (12) ◽  
pp. 1563-1570 ◽  
Author(s):  
Gordon Pritchard ◽  
Brian Pelchat
Keyword(s):  
Life Cycle ◽  
Rapid Growth ◽  
Growth And Development ◽  
Larval Growth ◽  
Head Capsule ◽  
Temperature Dependent ◽  
Vernal Equinox ◽  
Larval Instars ◽  
Head Capsule Width ◽  
Major Shift

AbstractSamples of a population of Argia vivida Hagen larvae were taken at about monthly intervals from a series of warm sulphur pools at Banff, Alberta, from June 1973 to December 1974. Changes in head capsule width and wing pad length in field-collected and laboratory-reared specimens show that the life-cycle is univoltine. Only the final (Z) instar can be recognized with certainty, but methods are described whereby the population can be divided into size classes which are thought to correspond well with the last nine larval instars. Periods of rapid growth occur in the autumn and again in the spring. Larvae overwinter in the instars U, V, W, X, and Y and the major shift to the final instar occurs in March and April. Adults emerge from April to August. In the laboratory, growth is temperature dependent until the penultimate (Y) instar and this could be a factor in the field since, although larvae can exist year-round at a constant 26 °C, some larvae live in the cooler areas at the edges of the streams and pools. Entry to the final instar appears to require the long photoperiods that follow the vernal equinox.

Nanoaggregates of Mn(III)tetraperfluorophenylporphyrin: a greener approach for allylic oxidation of olefins

2011 ◽  
Vol 15 (11n12) ◽  
pp. 1258-1264 ◽  
Author(s):  
Amit Aggarwal ◽  
Sunaina Singh ◽  
Charles M. Drain
Keyword(s):  
Catalytic Activity ◽  
Molecular Oxygen ◽  
Reaction Medium ◽  
Oxidation Products ◽  
Allylic Oxidation ◽  
Central Metal Atom ◽  
Central Metal ◽  
Organic Nanoparticles ◽  
Aqueous Solvent ◽  
Turn Over

Organic nanoparticles of metalloporphyrins can be a versatile catalyst for the selective oxidation of alkenes and other hydrocarbons. The catalytic activity of the metalloporphyrin depends on the nature of the central metal atom, peripheral groups, and the architecture of the porphyrin macrocycle. Herein, we report the catalytic activity of organic nanoparticles of 5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorophenyl)porphyrinato manganese(III), Mn (III)TPPF20, for the oxidation of cyclohexene using molecular oxygen as an oxidant in aqueous solvent under ambient conditions. While the solvated metalloporphyrins catalytically oxidize alkenes to the corresponding epoxide with a modest turn-over numbers, ca. 30 nm organic nanoparticles of Mn (III)TPPF20 have enhanced catalytic activity with up to a two-fold greater turn-over number and yields only allylic oxidation products. The activity of organic nanoparticles is slow compared to the solvated metalloporphyrins. These organic nanoparticles catalytic systems facilitate a greener reaction since ca. 89% of the reaction medium is water, molecular oxygen is used in place of man-made oxidants, and the ambient reaction conditions require less energy. This organic nanoparticle catalytic system also avoids using halogenated solvents commonly used in solution phase reactions. The enhanced catalytic activity of these organic nanoparticles is unexpected because the metalloporphyrins in the nanoaggregates are in the close proximity and the turn-over number should diminish by self-oxidative degradation.

scholarly journals IPTEKS PENGHITUNGAN SIKLUS HIDUP PERUSAHAAN (STUDI KASUS PADA PERUSAHAAN TERBUKA DI BURSA EFEK INDONESIA)

2019 ◽  
Vol 3 (2) ◽  
Author(s):  
Irene Florensia Pontoh
Keyword(s):  
Life Cycle ◽  
Rapid Growth ◽  
Business Strategy ◽  
Mature Stage ◽  
Retained Earnings

Rapid growth of economics makes many firms continue to develop their business. Along with the rapid growth of business the high competition rising between firms in term to snatch the market or consumers. The higher of competition gives an impact to firms life cycle which makes many firms keep develop their business strategy to attract the investors and consumers. Under assumption that the median is 0.76 based on sample, the result of calculation of the retained earnings to total equity (RETE) in period of 2016 shows that life cycle of each firms are varies. The result shows that firms under median are not at mature stage while firms above median are categorized as mature firms.

Founders versus Descendants: The Profitability, Efficiency, Growth Characteristics and Financing in Large, Public, Founding-Family-Controlled Firms

1999 ◽  
Vol 12 (2) ◽  
pp. 123-131 ◽  
Author(s):  
Daniel L. McConaughy ◽  
G. Michael Phillips
Keyword(s):  
Life Cycle ◽  
Research And Development ◽  
Rapid Growth ◽  
Family Firm ◽  
Growth Characteristics ◽  
Early Years ◽  
Capital Assets ◽  
Founding Family ◽  
The Family

This study examines the differences between founder-controlled firms and firms controlled by descendants or relatives of the founder. In general, we observe that founder-controlled firms grow faster and invest more in capital assets and research and development. However, descendant-controlled firms are more profitable. The results are consistent with a life-cycle view of the family firm in which the early years are characterized by rapid growth. The experience of the early years provides a basis for later, when the firm is more professionally run and can exploit its established position in the market.

Environmental impacts of the life cycle of alluvial gold mining in the Peruvian Amazon rainforest

2019 ◽  
Vol 662 ◽  
pp. 940-951 ◽  
Author(s):  
Ramzy Kahhat ◽  
Eduardo Parodi ◽  
Gustavo Larrea-Gallegos ◽  
Carlos Mesta ◽  
Ian Vázquez-Rowe
Keyword(s):  
Life Cycle ◽  
Environmental Impacts ◽  
Gold Mining ◽  
Amazon Rainforest ◽  
Peruvian Amazon ◽  
Alluvial Gold

scholarly journals A User Identity Management System for Cybercrime Control

2021 ◽  
Vol 40 (1) ◽  
pp. 129-139
Author(s):  
T. Alese ◽  
O. Owolafe ◽  
A.F. Thompson ◽  
B.K. Alese
Keyword(s):  
Life Cycle ◽  
Rapid Growth ◽  
Management System ◽  
Identity Management ◽  
Identity Theft ◽  
Remote Access ◽  
Identity Management System ◽  
Digital Identities ◽  
Biometric Features ◽  
Authentication Technique

The rapid growth in the number of online services has lead to an increasing number of different identities managed by each user that makes people feel overloaded and suffer from password fatigue. This poses a serious problem and makes people unable to control and protect their digital identities against identity theft. As organizations grow and adds services such as ecommerce and global remote access of services, controlling who is accessing what kind of information is also becoming a difficult task. This research therefore, presents the development of a user identity management system for cybercrime control. The four stages of an identity management life cycle were developed using some mathematical tools. A two-factor authentication technique was used in developing the system, the traditional username and password was also included with biometric features for robustness. A simulation was run on the model for users ranging from 10 to 1000 using life wild dataset, and accuracy was found to be 98.01%.

scholarly journals A study of some Biological Aspects of Procellio scaber(Isopoda : porcellionidae) Latrellile 1804In Al-jadriyia region /Baghdad-Iraq

2010 ◽  
Vol 7 (4) ◽  
pp. 1310-1316
Author(s):  
Baghdad Science Journal
Keyword(s):  
Life Cycle ◽  
Population Density ◽  
Rapid Growth ◽  
Dry Weight ◽  
The Body ◽  
Spring Season ◽  
Large Size ◽  
Large Numbers ◽  
Biological Aspects ◽  
Time Of Year

A study of some biological aspects of the crustacean Isopod procellio scaber was carried out for the period April 2003 to march 2004 . The study consisted reproductive and morphological characteristies such as size , weight and length of the body . The result showed that the highest population density of P. scaber was 1120 individual/m2 in September 2003 and less density 403 ind/m2 in February 2004. The density was generally high in Spring and Autumn, low in Summer and Winter months.An increase of the sexual ratio appear in the females number compared to males number (p < 0.05) during most of year. Present study showed non significant increase in the length and dry weight for females compared to males in most of year months. There were two seasons for reproduction, first starts in February to the ends of August, the second season starts in September,to the end in January. A number of Juveniles recorded during most time of year. While the percentage decreased during the Winter months and nearly disappeared during December. The large size individuals dominated during the Spring season which may be due to their rapid growth. The results showed that the moult individuals in different sizes class present for most year months, in large numbers small sizes class include due to their rapid growth. Life cycle data showed four biological stages: eggs, Manca, Juvenile and Mature stages. The female put between (2-70) eggs per each breed. There is one or tow breed for female in year.

A Cloud-Based Approach to Support the Mobile Phone Recycling Industry in China

2016 ◽  
Author(s):  
Wenyan Zhao ◽  
Xi Vincent Wang ◽  
Jianxin Yang ◽  
Bo Li ◽  
Lihui Wang
Keyword(s):  
Life Cycle ◽  
Mobile Phone ◽  
Mobile Phones ◽  
Policy Maker ◽  
Rapid Growth ◽  
Sharp Increase ◽  
Data System ◽  
Recycling Industry ◽  
Recyclable Resources ◽  
Whole Life Cycle

In recent years, the waste mobile phones are generated in large quantity in China. Those e-wastes gain more and more attention because of both the sharp increase in quantity and the recyclable resources they contain. Furthermore, the mobile phone recycling industry has experienced a trend of rapid growth as well. However, due to the lack of national policies and legislations, the recycling industry is now facing problems in recycling processes. Thus in this paper, mobile phone recycling industry in China is systematically analyzed and a Cloud-based approach is developed which integrates tracking, interaction and coordinator mechanism through the recycling processes. With the integration of various stakeholders, the system can provide integrated data system throughout the whole life cycle of the mobile phones for the policy maker, and provide guidance for the operations during recycling service for the recycling stakeholders.

scholarly journals The Aseptic Culture of Arabidopsis Thaliana (l.) Heynh.

1957 ◽  
Vol 10 (3) ◽  
pp. 243 ◽  
Author(s):  
J Langridge
Keyword(s):  
Arabidopsis Thaliana ◽  
Life Cycle ◽  
Chromosome Number ◽  
Rapid Growth ◽  
Optimal Growth ◽  
Life Cycles ◽  
High Fertility ◽  
Aseptic Culture ◽  
Other Substances ◽  
Aseptic Conditions

Arabidopsis thaliana (L.) Heynh. is a small, rapidly growing crucifer with a 28-day life cycle, a low chromosome number (n=5), and a high fertility (152�1l seeds under aseptic conditions). The small size and rapid growth of the plants enable them to be grown throughout their life cycles on sterile, nutrient agar in ordinary' test tubes. Alternatively, up to 50 plants may be grown on silica gel in crystallizing dishes. For optimal growth the trace element cations should be chelated and light should be excluded from the roots. When supplied with sucrose the plants absorb only the glucose portion. During growth the plants excrete small quantities of vitamins and other substances into the medium but not in amounts likely to prevent the detection of growth mutants through cross-feeding.

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