A Comprehensive Observational Based Multiphase Chemical Model Analysis of the Sulfur Dioxide Oxidations in both Summer and Winter

Abstract. Sulfate is one of the main components of the haze particles and the formation mechanism remains controversial. Lacking of detailed and comprehensive field data hindes the accurate evaluation of relative roles of prevailing sulphate formation pathways. Here, we analyzed the sulfate production rates using a state-of-art multiphase model constrained to the observed concentrations of transition metal ions (TMI), nitrogen dioxide, ozone, hydrogen peroxide, and other important parameters in winter and summer in the North China Plain. Our results showed that aqueous TMI-catalyzed oxidation was the most important pathway followed by the surface oxidation of Mn in both winter and summer, while the hydroxyl and criegee radicals oxidations contribute significantly in summer. In addition, we also modeled the published cases for the fog and cloud conditions. It is found that nitrogen dioxide oxidation is the dominant pathway for the fog in a higher pH range while hydroperoxide and ozone oxidations dominated for the cloud.

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A comprehensive observation-based multiphase chemical model analysis of sulfur dioxide oxidations in both summer and winter

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-13713-2021 ◽

2021 ◽

Vol 21 (17) ◽

pp. 13713-13727

Author(s):

Huan Song ◽

Keding Lu ◽

Can Ye ◽

Huabin Dong ◽

Shule Li ◽

...

Keyword(s):

Transition Metal ◽

Nitrogen Dioxide ◽

Metal Ion ◽

Fine Particles ◽

Surface Oxidation ◽

Multiphase Model ◽

Sulfate Production ◽

The North ◽

Ph Range ◽

Main Components

Abstract. Sulfate is one of the main components of haze fine particles, and its formation mechanism remains controversial. A lack of detailed and comprehensive field data hinders the accurate evaluation of relative roles of prevailing sulfate formation pathways. Here, we analyzed the sulfate production rates using a state-of-the-art multiphase model constrained to the observed concentrations of transition metal, nitrogen dioxide, ozone, hydrogen peroxide and other important parameters in winter and summer in the North China Plain. Our results showed that aqueous transition metal ion (TMI)-catalyzed oxidation was the most important pathway followed by the surface oxidation of Mn in both winter and summer while the hydroxyl and Criegee radical oxidations contribute significantly in summer. In addition, we also modeled the published cases for the fog and cloud conditions. It is found that nitrogen dioxide oxidation is the dominant pathway for the fog in a higher pH range while hydroperoxide and ozone oxidations dominated for the cloud.

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The Role of the Disulfide Bridge in the Copper (II) Binding by the Cyclic His4-Peptide

International Journal of Molecular Sciences ◽

10.3390/ijms22126458 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6458

Author(s):

Aleksandra Pieniężna ◽

Weronika Witak ◽

Aneta Szymańska ◽

Justyna Brasuń

Keyword(s):

Metal Ions ◽

Coordination Mode ◽

Transition Metal Ions ◽

Disulfide Bridge ◽

Chain Flexibility ◽

Vis Spectroscopy ◽

Ph Range ◽

Cd Studies ◽

Metal Ratios

In this paper, we present studies on the influence of the disulfide bridge on the copper (II) ions’ binding abilities by the cyclic His4-peptide. The studied ligand HKHPHRHC-S-S-C consists of nine amino acids. The cyclic structure was obtained through a disulfide bridge between two cysteinyl groups. Moreover, this peptide is characterized by the presence of four His residues in the sequence, which makes it an interesting ligand for transition metal ions. The potentiometric and spectroscopic (UV-Vis spectroscopy and circular dichroism spectroscopy (CD)) studies were carried out in various molar ligand to metal ratios: 2:1, 1:1, and 1:2, in the pH range of 2.5–11 at 25 °C. The results showed that the cyclic His4-peptide promotes dinuclear complexes in each of these systems and forms the final dinuclear species with the {NIm, 3N-amide}{NIm, 3N-amide} coordination mode. The obtained data shows that cyclization by the formation of the disulfide bond has an impact on the peptide chain flexibility and appearance of additional potential donors for metal ions and influences the copper (II) ions’ coordination.

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GGE Biplot projection in discriminating the efficiency of popcorn lines to use nitrogen

Ciência e Agrotecnologia ◽

10.1590/1413-70542017411030816 ◽

2017 ◽

Vol 41 (1) ◽

pp. 22-31 ◽

Cited By ~ 8

Author(s):

Adriano dos Santos ◽

Antônio Teixeira do Amaral Júnior ◽

Railan do Nascimento Ferreira Kurosawa ◽

Ismael Fernando Schegoscheski Gerhardt ◽

Roberto Fritsche Neto

Keyword(s):

Nitrogen Availability ◽

Block Design ◽

Germplasm Collection ◽

Inbred Lines ◽

Gge Biplot ◽

State University ◽

Information Ratio ◽

The North ◽

Randomized Block Design ◽

Main Components

ABSTRACT Nitrogen is essential for sustaining life on the planet, and it is the most important nutrient for obtaining high agricultural production. However, their use leads to the release of nitrous oxide with a global warming potential 296 times higher than the CO2 molecule, making it a challenge to reduce their use in agriculture. The objective of this research was to identify efficient popcorn inbred lines and responsive nitrogen use and exhibit a good expansion volume. For this, 29 inbred lines from the Germplasm Collection of Darcy Ribeiro North Fluminense State University (UENF) were evaluated at two contrasting levels of nitrogen availability (low and ideal) at two representative locations in the north and northwest of the state of Rio de Janeiro, Brazil, arranged in a randomized block design with three replicates. These inbred lines were discriminated against efficient use of nitrogen by multivariate GGE Biplot. Selective accuracy was close to 1, showing that the genotypes were enough to provide contrasting success in selection procedures. The first two main components (PC) retained 93.82% of the total variation, and PC1 furnished an information ratio (IR) that was unaffected by noise. L77 was the most unstable line, while P7, P2, P6, P3, P5, P4, P9, P10, P8, P9, L70, L74, and L55 were efficient and responsive. The GGE biplot method is recommended for the reliable identification of popcorn lines that are efficient and responsive to the use of nitrogen.

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Evaluation of the modern geoecological state of the fjords of the eastern Barents sea

10.29006/978-5-6045110-0-8/(37) ◽

2021 ◽

pp. 899-943

Author(s):

V.A. Shakhverdov ◽

◽

D.V. Ryabchuk ◽

M.A. Spiridonov ◽

V.A. Zhamoida ◽

...

Keyword(s):

Bottom Sediments ◽

Industrial Development ◽

Barents Sea ◽

Chemical Elements ◽

Environmental Damage ◽

North West ◽

Geochemical Zoning ◽

The North ◽

The Barents Sea ◽

Main Components

A brief analysis of the history of environmental geological study of the Barents Sea is given. It shows that at the beginning of industrial development the geological environment was characterized by a low level of disturbance and pollution. On example of the Kola Bay, an assessment of the current environmental geological conditions of the fjords in the eastern part of the Barents Sea is given. Seismic-acoustic studies confirm the predominantly tectonic origin of the bay and the hazardous spread of gravitational rocks movement within the coastal slopes. The background geochemical characteristics of recent bottom sediments are quantified. It is shown that geochemical zoning of the bottom of the bay is a consequence of both natural and anthropogenic processes. According to the content of Cu, Zn, As, Cd, Pb, Hg and hexane-soluble petroleum products (PP) in the bottom sediments, the characteristics of various areas were obtained. It is shown that the distribution of PP and several other pollutants in the main components of aquatic and coastal geosystems is a leading element of the environmental monitoring system, quantitative assessment of anthropogenic impact and accumulated environmental damage. Active economic activity within the southern leg of the Kola Bay, as well as the naval bases, significantly affects the distribution of chemical elements. The data concerning distribution of chemical elements forms in bottom sediments are given that suggest a high probability of secondary pollution of the bottom water when the physicochemical conditions of sedimentation processes change. A comparative analysis showed that bottom sediments of the Kola Bay are characterized by the highest concentration of chemical elements in the North-West Region of the Russian Federation.

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38 Improving Access to Outpatient Services for Older People Using A Clinical Microsystems Approach

Age and Ageing ◽

10.1093/ageing/afz185.01 ◽

2020 ◽

Vol 49 (Supplement_1) ◽

pp. i11-i13

Author(s):

E Tullo ◽

A Smith ◽

J Ridden ◽

R Ross ◽

R Curless ◽

...

Keyword(s):

Older People ◽

Emergency Services ◽

Waiting Times ◽

Outpatient Services ◽

North East ◽

The North ◽

Team Coaching ◽

Complex Patients ◽

Clinical Microsystems ◽

Main Components

Abstract Background Northumbria Healthcare NHS Foundation Trust provides services to more than 500,000 residents in the North-East of England across multiple sites. Local problem Outpatient services for older people across Northumbria include specialist (eg falls) and generic clinics with differing referral routes, demands and waiting times. Referrals derive from primary care, emergency services and elsewhere; some are complex patients requiring a comprehensive geriatric assessment (CGA). Existing pathways led to variable waits for clinics, duplication and delays. Aim was to improve the timeliness, efficiency and access to appropriate assessment first time. Methods We adopted a Clinical Microsystems approach (Sheffield Microsystems Coaching Academy) for improvement. Main components were team coaching, weekly “Big Room” meeting of involved staff to share understanding of current process, agree change ideas, and test these with multiple plan, do, study, act (PDSA) cycles. Impacts of each PDSA cycle were discussed in Big Room, leading to refinement of the pathway. Interventions Results: PDSA interventions were tested over 6 months: Development of a single triage systemCGA clinic for frail older patients.Development of shared documentation for CGA.Improved cycle and lead times for assessment Conclusions Our quality improvement work supported the development and implementation of a new referral triage process with CGA assessment for complex frail patients. The change has reduced patient wait times, provided early intervention and reduced duplication. Work is ongoing to determine impact on patient satisfaction and time to discharge from clinic. The approach taken by this project could be applied elsewhere to improve outpatient referral processes.

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Kinetics of the Nitrogen Dioxide Catalyzed Oxidation of Nitric Oxide

The Journal of Chemical Physics ◽

10.1063/1.1743543 ◽

1957 ◽

Vol 26 (5) ◽

pp. 984-988 ◽

Cited By ~ 10

Author(s):

James D. Ray ◽

Richard A. Ogg

Keyword(s):

Nitric Oxide ◽

Nitrogen Dioxide ◽

Kinetics Of ◽

Catalyzed Oxidation

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A Highly Selective and Sensitive Fluorescent Probe Based on Quinolone Derivative for Hg2+ in Aqueous Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.549.229 ◽

2012 ◽

Vol 549 ◽

pp. 229-233

Author(s):

Juan Juan Tian ◽

Xin Zhou ◽

Hui Juan Hao ◽

Xue Wu

Keyword(s):

Aqueous Solution ◽

Fluorescent Probe ◽

Limit Of Detection ◽

Transition Metal Ions ◽

Quinoline Derivative ◽

Ligand Complex ◽

Quinolone Derivative ◽

Ph Range ◽

Metal Ligand ◽

Tof Ms

A new fluorescent probe, quinoline derivative DPQ bearing a methyl pyrrolidine-1-carbodithioate group, was synthesized and characterized by IR, Tof-MS and NMR. Its fluorescent behaviors toward transition metal ions were investigated. The results indicate that DPQ shows unique selective and high sensitive for Hg2+ in aqueous solution with a broad pH range 4-10. DPQ forms a 1:2 metal-ligand complex with Hg2+ ions with a limit of detection as low as 1.7×10-6 mol/L.

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Chemical and enzymatic characterization of recombinant rabbit muscle pyruvate kinase

Biological Chemistry ◽

10.1515/hsz-2012-0334 ◽

2013 ◽

Vol 394 (5) ◽

pp. 695-701 ◽

Cited By ~ 2

Author(s):

Christian Boehme ◽

Frank Bieber ◽

Julia Linnemann ◽

Reinhard Breitling ◽

Stefan Lorkowski ◽

...

Keyword(s):

Metal Ions ◽

Pyruvate Kinase ◽

Adenosine Diphosphate ◽

Transition Metal Ions ◽

Recombinant Enzyme ◽

High Yield ◽

Rabbit Muscle ◽

Reading Frame ◽

Ph Range ◽

Muscle Pyruvate Kinase

Abstract The stepwise synthesis of thymidine triphosphate (TTP) requires a kinase for phosphorylation in the last step. Because pyruvate kinase (PK) using phosphoenolpyruvate (PEP) as substrate can regenerate adenosine triphosphate and phosphorylate thymidine diphosphate as well, we chose this enzyme for the synthesis of TTP via an enzymatic cascade reaction. The metalloenzyme PK shows pronounced promiscuity and therefore fits well to the conditions of this reaction. PK commonly used today is isolated from rabbit muscle. We cloned and expressed the respective open reading frame in Escherichia coli, purified, and characterized the His-tagged recombinant enzyme. The enzyme has an activity optimum at 37°C and in the pH range from 7.4 to 7.8. Km constants conformed well with the isolated native enzyme for adenosine diphosphate (ADP) to 0.37±0.02 mm and for PEP to 0.07±0.01 mm. The recombinant enzyme shows the following range in its substrate specificity: ADP>dADP>dGDP>dCDP>thymidine diphosphate (TDP). It allows the phosphorylation of TDP to TTP in high yield (up to 95%). The metal ions Mg2+ and K+ are necessary for full enzymatic activity. The addition of transition metal ions such as Mn2+, Cu2+, Co2+, and Ni2+ reduces activity. Storage of the enzyme at -20°C retains full activity.

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Resilience analysis for agricultural systems of north China plain based on a dynamic system model

Scientia Agricola ◽

10.1590/s0103-90162011000100002 ◽

2011 ◽

Vol 68 (1) ◽

pp. 8-17 ◽

Cited By ~ 9

Author(s):

Hongjun Li ◽

Zhijun Liu ◽

Li Zheng ◽

Yuping Lei

Keyword(s):

Food Security ◽

North China Plain ◽

North China ◽

System Model ◽

Agricultural Systems ◽

Time Step ◽

The North ◽

Labor Transfer ◽

Main Components ◽

The Cost

This paper presents a case study of resilience theory to understand agricultural systems in the Luancheng County of the North China Plain. A dynanic system model coupled with social, economic and ecological subsystems of agriculture for the Luancheng County was constructed with a time step of one month. The model includes five main components, water resources, profitability, irrigation, crop yield and area. The simulated groundwater table, wheat area and yield, maize area and yield, and rural labor transfer reflected the general trend of the observed data, with calculated determination coefficients higher than 0.88. Resilience of agricultural systems, as indicated by agricultural profitability and food security, were explored for the Luancheng County. Initially, investments in agriculture increased its resilience rapidly. However, with the degradation of resources and the increases in agricultural investment, the cost of agricultural production became too high to gain profit. The rise in population increases the risk of food security. As a result, the resilience of agricultural systems decreased gradually. The Luancheng County is now in the conservation phase of the adaptive cycle. Partial adjustments should be introduced to enhance its resilience and promote the continuing development of the agricultural systems.

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