scholarly journals Critical assessment of the current state of scientific knowledge, terminology, and research needs concerning the role of organic aerosols in the atmosphere, climate, and global change

2006 ◽  
Vol 6 (7) ◽  
pp. 2017-2038 ◽  
Author(s):  
S. Fuzzi ◽  
M. O. Andreae ◽  
B. J. Huebert ◽  
M. Kulmala ◽  
T. C. Bond ◽  
...  
Keyword(s):  
Organic Aerosols ◽  
Chemical Properties ◽  
Research Priorities ◽  
Future Research ◽  
Current State ◽  
Basic Set ◽  
Physical And Chemical ◽  
Present Understanding ◽  
Key Questions

Abstract. In spite of impressive advances in recent years, our present understanding of organic aerosol (OA) composition, physical and chemical properties, sources and transformation characteristics is still rather limited, and their environmental effects remain highly uncertain. This paper discusses and prioritizes issues related to organic aerosols and their effects on atmospheric processes and climate, providing a basis for future activities in the field. Four main topical areas are addressed: i) sources of OA; ii) formation transformation and removal of OA; iii) physical, chemical and mixing state of OA; iv) atmospheric modelling of OA. Key questions and research priorities regarding these four areas are synthesized in this paper, and outstanding issues for future research are presented for each topical area. In addition, an effort is made to formulate a basic set of consistent and universally applicable terms and definitions for coherent description of atmospheric OA across different scales and disciplines.

scholarly journals Critical assessment of the current state of scientific knowledge, terminology, and research needs concerning the role of organic aerosols in the atmosphere, climate, and global change

2005 ◽  
Vol 5 (6) ◽  
pp. 11729-11780 ◽  
Author(s):  
S. Fuzzi ◽  
M. O. Andreae ◽  
B. J. Huebert ◽  
M. Kulmala ◽  
T. C. Bond ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Scientific Progress ◽  
Chemical Properties ◽  
Research Priorities ◽  
Organic Aerosol ◽  
Lower Atmosphere ◽  
Future Research ◽  
Basic Set ◽  
Collaborative Activities ◽  
Physical And Chemical

Abstract. In spite of impressive advances in recent years, our present understanding of organic aerosol (OA) composition, physical and chemical properties, sources and transformation characteristics is still rather limited, and their environmental effects remain highly uncertain. Therefore, the three atmosphere-related projects of the International Geosphere Biosphere Programme (IGBP) – IGAC (International Global Atmospheric Chemistry Project), iLEAPS (Integrated Land Ecosystem Atmosphere Process Study) and SOLAS (Surface Ocean-Lower Atmosphere Study) – organised a workshop with the specific goal of discussing and prioritizing issues related to organic aerosol and their effects on atmospheric processes and climate, providing a basis for future collaborative activities at the international level. Four main topical areas were addressed: (a) sources of OA; (b) formation and transformation of OA; (c) physical and chemical state of OA; (d) atmospheric modelling of OA. Key questions and research priorities regarding these four areas have been synthesized in this paper, and outstanding issues for future research are presented for each topical area. In addition, an effort is made to formulate a basic set of consistent and universally applicable terms and definitions for coherent description of atmospheric OA across different scientific scales and disciplines. In fact, the terminologies used in the past and present scientific literature are not always consistent, and this may lead to misunderstandings and confusion in the communication between specialists from different disciplines and potentially inhibit or retard scientific progress.

State of the Art: Addressing the INGO ‘Legitimacy Deficit’

2005 ◽  
Vol 3 (2) ◽  
pp. 175-192 ◽  
Author(s):  
Vivien Collingwood ◽  
Louis Logister
Keyword(s):  
Global Governance ◽  
World Order ◽  
Alternative Conceptions ◽  
Future Research ◽  
The Past ◽  
Current State ◽  
Universal Human Rights ◽  
Working Practices ◽  
Key Questions

While the numbers and competencies of international non-governmental organisations (INGOs) have increased dramatically in the past few decades, questions have been raised about the legitimacy of their new activities. A number of scholars have identified significant tensions between INGOs-™ legitimacy claims and the realities of their working practices. We examine the current state of the debate on INGO legitimacy in two contrasting literatures: normative work on global governance and its implications for the role of INGOs, and policy-oriented work on INGOs-™ legitimacy. The first shows how INGO involvement in global governance opens the door to a range of alternative conceptions of world order, rooted in notions of universal human rights, democracy, and theories of redistributive justice. The latter set of voices is concerned less with locating INGOs-™ roles as agents in global normative structures than with analysing concrete problems arising from increased INGO participation in the development process. Future research might take into account key questions concerning the sources and the scope and nature of INGO legitimacy.

Trade Union Membership and Job Satisfaction

1987 ◽  
Vol 17 (4) ◽  
pp. 160-164 ◽  
Author(s):  
Stephen D. Bluen ◽  
Caroline van Zwam
Keyword(s):  
Job Satisfaction ◽  
Union Membership ◽  
Research Priorities ◽  
Future Research ◽  
Non Union ◽  
Study Results ◽  
Worker Satisfaction ◽  
The Relationship ◽  
Moderating Role

The relationship between union membership and job satisfaction, and the moderating role of race and sex is considered in this study. Results show that both race and sex interact with union membership in predicting job satisfaction. A significant 2 × 2 × 2 (union membership × race × sex) interaction showed that white, non-unionized females were less satisfied with their work than black, non-unionized females. In addition, sex moderated the relationship between union membership and co-worker satisfaction: Whereas unionized males were more satisfied with their co-workers than unionized females, the opposite was true for the non-unionized subjects. Finally, union members and non-members differed regarding promotion opportunities: Union members were more satisfied with their promotion opportunities than non-union members. On the basis of the findings, implications and future research priorities are discussed.

Transportation pathways of pesticides in two major watersheds of Istanbul, Turkey

2004 ◽  
Vol 49 (3) ◽  
pp. 165-172 ◽  
Author(s):  
M. Yazgan ◽  
A. Tanik
Keyword(s):  
Chemical Properties ◽  
Surface Flow ◽  
Priority List ◽  
Pesticide Pollution ◽  
Consumption Values ◽  
Annual Consumption ◽  
Agricultural Areas ◽  
Physical And Chemical ◽  
And Chemical Properties

The study covers the investigation of pesticides in terms of consumption, toxicological classification and various intrinsic physical and chemical properties like DT50, KOC, GUS, solubility that describe the important mechanisms prevailing in soil, namely persistence and mobility. These mechanisms help to estimate the transportation pathways of pesticides on soil till they reach the receiving water after being applied on land. Classification is done in three groups, those likely to appear in surface flow, those that appear in groundwater and those that present transient conditions. Such an approach that also takes into account toxicological levels and annual consumption values of pesticides will act as a tool to prepare the priority list of pesticides that need special care during their transportation. The fate of pesticides is a difficult task to solve, however, such a methodology, puts forth a rough estimate on their behavior in spite of uncertainties in many of the parameters describing mechanisms like persistence and mobility. The agricultural areas of two watersheds of Istanbul are selected as target areas to describe the approach, which is also checked with another approach estimating pesticide pollution potential that considers various other properties of pesticides. Almost similar findings are depicted with 85% proximity. The methodology presented in the paper illustrates and emphasizes the significant role of pesticide properties in determining their fate in soil after being applied.

The Advancement of Neuroimaging Research Investigating Developmental Stuttering

2011 ◽  
Vol 21 (3) ◽  
pp. 88-95 ◽  
Author(s):  
Deryk S. Beal
Keyword(s):  
Speech Production ◽  
Fast Rate ◽  
Neural Correlates ◽  
Future Research ◽  
Current State ◽  
Developmental Stuttering ◽  
The Brain ◽  
State Of The Field

We are amassing information about the role of the brain in speech production and the potential neural limitations that coincide with developmental stuttering at a fast rate. As such, it is difficult for many clinician-scientists who are interested in the neural correlates of stuttering to stay informed of the current state of the field. In this paper, I aim to inspire clinician-scientists to tackle hypothesis-driven research that is grounded in neurobiological theory. To this end, I will review the neuroanatomical structures, and their functions, which are implicated in speech production and then describe the relevant differences identified in these structures in people who stutter relative to their fluently speaking peers. I will conclude the paper with suggestions on directions of future research to facilitate the evolution of the field of neuroimaging of stuttering.

Di-imide: Some Physical and Chemical Properties, and the Kinetics and Stoichiometry of the Gas-phase Decomposition

1973 ◽  
Vol 51 (21) ◽  
pp. 3605-3619 ◽  
Author(s):  
C. Willis ◽  
R. A. Back
Keyword(s):  
Gas Phase ◽  
Room Temperature ◽  
Chemical Properties ◽  
Phase Decomposition ◽  
Important Intermediate ◽  
Long Lifetime ◽  
Physical And Chemical ◽  
Text Formation ◽  
Kinetics Of

Preparation of di-imide by passing hydrazine vapor through a microwave discharge yields mixtures with NH3 containing typically about 15% N2H2, estimated from the gases evolved on decomposition. The behavior of the mixture (which melts at −65 °C) on warming from −196 to −30 °C suggests a strong interaction between the components. Measurements of magnetic susceptibility and e.p.r. experiments showed that N2H2 is not strongly paramagnetic, which with other observations points to a singlet rather than a triplet ground-state.Di-imide can be vaporized efficiently, together with NH3, by rapid warming, and the vapor is surprisingly long-lived, with a typical half-life of several minutes at room temperature. The near-u.v. (3200–4400 Å) absorption spectrum of the vapor was photographed; it shows well-defined but diffuse bands, with εmax = 6(± 3) at 3450 Å.Di-imide decomposes at room temperature in two ways:[Formula: see text][Formula: see text]Formation of NH3 was not observed but cannot be ruled out. The decomposition of the vapor is complicated by a sizeable and variable decomposition that occurs rapidly during the vaporization. The stoichiometry of this and the vapor-phase decomposition depends on total pressure and di-imide concentration. The kinetics of the decomposition of the vapor were studied from 22 to 200 °C by following the disappearance of N2H2 by absorption of light at 3450 Å, or the formation of N2H4 by absorption at 2400 Å, and by mass spectrometry. The kinetics are complex and can be either first- or second-order, or mixed, depending on surface conditions. The effect of olefin additives on the decomposition was studied, and is also complex.Mechanisms for the decomposition are discussed, including the possible role of trans-cis isomerization. The relatively long lifetime found for di-imide in the gas phase suggests that it may be an important intermediate in many reactions of hydronitrogen systems.

scholarly journals An Overview of Dynamic Heterogeneous Oxidations in the Troposphere

Environments ◽  
2018 ◽  
Vol 5 (9) ◽  
pp. 104 ◽  
Author(s):  
Elizabeth Pillar-Little ◽  
Marcelo Guzman
Keyword(s):  
Atmospheric Aerosols ◽  
Atmospheric Transport ◽  
Cloud Condensation Nuclei ◽  
Complex Mixture ◽  
Organic Aerosols ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
The Impact ◽  
And Chemical Properties

Due to the adverse effect of atmospheric aerosols on public health and their ability to affect climate, extensive research has been undertaken in recent decades to understand their sources and sinks, as well as to study their physical and chemical properties. Atmospheric aerosols are important players in the Earth’s radiative budget, affecting incoming and outgoing solar radiation through absorption and scattering by direct and indirect means. While the cooling properties of pure inorganic aerosols are relatively well understood, the impact of organic aerosols on the radiative budget is unclear. Additionally, organic aerosols are transformed through chemical reactions during atmospheric transport. The resulting complex mixture of organic aerosol has variable physical and chemical properties that contribute further to the uncertainty of these species modifying the radiative budget. Correlations between oxidative processing and increased absorptivity, hygroscopicity, and cloud condensation nuclei activity have been observed, but the mechanisms behind these phenomena have remained unexplored. Herein, we review environmentally relevant heterogeneous mechanisms occurring on interfaces that contribute to the processing of aerosols. Recent laboratory studies exploring processes at the aerosol–air interface are highlighted as capable of generating the complexity observed in the environment. Furthermore, a variety of laboratory methods developed specifically to study these processes under environmentally relevant conditions are introduced. Remarkably, the heterogeneous mechanisms presented might neither be feasible in the gas phase nor in the bulk particle phase of aerosols at the fast rates enabled on interfaces. In conclusion, these surface mechanisms are important to better understand how organic aerosols are transformed in the atmosphere affecting the environment.

Air

2020 ◽  
pp. 139-177
Author(s):  
John Evans
Keyword(s):  
Carbon Capture ◽  
High Performance ◽  
Internal Combustion Engines ◽  
Atmospheric Oxygen ◽  
Carbon Capture And Storage ◽  
Chemical Properties ◽  
Energy Capture ◽  
Physical And Chemical ◽  
And Storage

The chemical properties of the volatile elements in groups 15 to 18 are outlined, showing how the the periodicicty of the properties of the elements shapes their chemistry. The manufacture of hydrogen and chlorine is described, showing how mercury-free methods have been developed for the latter. The effect of the formation of atmospheric CO2 on atmospheric oxygen content is explained in terms of dissolution in the oceans. Remediation of the exhaust gases from internal combustion engines by catalysts to remove CO2, NOx and carbonaceous particulates is explained. Options for carbon capture and storage by physical and chemical processes are evaluated, and examples provided of these processes in operation. Exploitation of the atmosphere for energy capture using wind turbines has been aided by the development of high performance magnets. The basis of these magnets and the role of rare earth elements is explained.

scholarly journals Identifying Potential Leakage Zones in an Irrigation Supply Channel by Mapping Soil Properties Using Electromagnetic Induction, Inversion Modelling and a Support Vector Machine

Soil Systems ◽  
2020 ◽  
Vol 4 (2) ◽  
pp. 25
Author(s):  
Ehsan Zare ◽  
Nan Li ◽  
Tibet Khongnawang ◽  
Mohammad Farzamian ◽  
John Triantafilis
Keyword(s):  
Electrical Conductivity ◽  
Support Vector Machine ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Future Research ◽  
Support Vector ◽  
Stream Channels ◽  
Supply Channel ◽  
Physical And Chemical ◽  
And Chemical Properties

The clay alluvial plains of Namoi Valley have been intensively developed for irrigation. A condition of a license is water needs to be stored on the farm. However, the clay plain was developed from prior stream channels characterised by sandy clay loam textures that are permeable. Cheap methods of soil physical and chemical characterisations are required to map the supply channels used to move water on farms. Herein, we collect apparent electrical conductivity (ECa) from a DUALEM-421 along a 4-km section of a supply channel. We invert ECa to generate electromagnetic conductivity images (EMCI) using EM4Soil software and evaluate two-dimensional models of estimates of true electrical conductivity (σ—mS m−1) against physical (i.e., clay and sand—%) and chemical properties (i.e., electrical conductivity of saturated soil paste extract (ECe—dS m−1) and the cation exchange capacity (CEC, cmol(+) kg−1). Using a support vector machine (SVM), we predict these properties from the σ and depth. Leave-one-site-out cross-validation shows strong 1:1 agreement (Lin’s) between the σ and clay (0.85), sand (0.81), ECe (0.86) and CEC (0.83). Our interpretation of predicted properties suggests the approach can identify leakage areas (i.e., prior stream channels). We suggest that, with this calibration, the approach can be used to predict soil physical and chemical properties beneath supply channels across the rest of the valley. Future research should also explore whether similar calibrations can be developed to enable characterisations in other cotton-growing areas of Australia.

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