New Spectrophotometric Method for Quantitative Characterization of Density-Driven Convective Instability

CO2 convective dissolution has been regarded as one of the fundamental mechanisms to accelerate the mass transfer of CO2 into brine. We present a new spectrophotometric method to characterize the convective instability and measure the dissolved CO2 mass, which enables the real-time quantitative visualization of CO2/brine transport mechanisms. Successive images were captured to identify the finger development regimes, and the convection morphologies were analyzed by the fingers length and affected area. CO2 solubility was experimentally studied, and the results are in agreement with the theoretical calculations. CO2 mass transfer flux was investigated as the Sherwood number changed. The increase in salinity and temperature has a negative effect on CO2 dissolution; here, numerical simulation and experimental phenomena are qualitatively consistent. In general, these findings confirm the feasibility of the method and improve the understanding of the physical process of CO2 convective dissolution, which can help assess the CO2 solubility trapping mass.

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Characterization of dissolved material during the initial phase of softwood kraft pulping

TAPPI Journal ◽

10.32964/tj12.1.37 ◽

2013 ◽

Vol 12 (1) ◽

pp. 37-43 ◽

Cited By ~ 1

Author(s):

HANNU PAKKANEN ◽

TEEMU PALOHEIMO ◽

RAIMO ALÉN

Keyword(s):

Mass Transfer ◽

Molecular Mass ◽

Initial Phase ◽

Degradation Products ◽

Kraft Pulping ◽

Reaction Products ◽

Cooking Temperature ◽

Molecular Masses ◽

Aliphatic Carboxylic Acids

The influence of various cooking parameters, such as effective alkali, cooking temperature, and cooking time on the formation of high molecular mass lignin-derived and low molecular mass carbohydrates-derived (aliphatic carboxylic acids) degradation products, mainly during the initial phase of softwood kraft pulping was studied. In addition, the mass transfer of all of these degradation products was clarified based on their concentrations in the cooking liquor inside and outside of the chips. The results indicated that the degradation of the major hemicellulose component, galactoglucomannan, typically was dependent on temperature, and the maximum degradation amount was about 60%. In addition, about 60 min at 284°F (140°C) was needed for leveling off the concentrations of the characteristic reaction products (3,4-dideoxy-pentonic and glucoisosaccharinic acids) between these cooking liquors. Compared with low molecular mass aliphatic acids, the mass transfer of soluble lignin fragments with much higher molecular masses was clearly slower.

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Global characterization of hydrodynamics and gas-liquid mass transfer in a thin-gap bubble column intended for microalgae cultivation

Chemical Engineering and Processing - Process Intensification ◽

10.1016/j.cep.2017.10.009 ◽

2017 ◽

Vol 122 ◽

pp. 76-89 ◽

Cited By ~ 7

Author(s):

Charlène Thobie ◽

Emilie Gadoin ◽

Walid Blel ◽

Jérémy Pruvost ◽

Caroline Gentric

Keyword(s):

Mass Transfer ◽

Bubble Column ◽

Microalgae Cultivation ◽

Liquid Mass ◽

Liquid Mass Transfer

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Rhizosphere-enriched microbes as a pool to design synthetic communities for reproducible beneficial outputs

FEMS Microbiology Ecology ◽

10.1093/femsec/fiz138 ◽

2019 ◽

Cited By ~ 6

Author(s):

Maria-Dimitra Tsolakidou ◽

Ioannis A Stringlis ◽

Natalia Fanega-Sleziak ◽

Stella Papageorgiou ◽

Antria Tsalakou ◽

...

Keyword(s):

Antifungal Activity ◽

Fungal Pathogens ◽

Growth Parameters ◽

Tomato Plants ◽

Beneficial Effects ◽

Negative Effect ◽

Tomato Growth ◽

In Vitro Antifungal Activity

Abstract Composts represent a sustainable way to suppress diseases and improve plant growth. Identification of compost-derived microbial communities enriched in the rhizosphere of plants and characterization of their traits, could facilitate the design of microbial synthetic communities (SynComs) that upon soil inoculation could yield consistent beneficial effects towards plants. Here, we characterized a collection of compost-derived bacteria, previously isolated from tomato rhizosphere, for in vitro antifungal activity against soil-borne fungal pathogens and for their potential to change growth parameters in Arabidopsis. We further assessed root-competitive traits in the dominant rhizospheric genus Bacillus. Certain isolated rhizobacteria displayed antifungal activity against the tested pathogens and affected growth of Arabidopsis, and Bacilli members possessed several enzymatic activities. Subsequently, we designed two SynComs with different composition and tested their effect on Arabidopsis and tomato growth and health. SynCom1, consisting of different bacterial genera, displayed negative effect on Arabidopsis in vitro, but promoted tomato growth in pots. SynCom2, consisting of Bacilli, didn't affect Arabidopsis growth, enhanced tomato growth and suppressed Fusarium wilt symptoms. Overall, we found selection of compost-derived microbes with beneficial properties in the rhizosphere of tomato plants, and observed that application of SynComs on poor substrates can yield reproducible plant phenotypes.

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Identification and Functional Characterization of a Cold-Related Protein, BcHHP5, in Pak-Choi (Brassica rapa ssp. chinensis)

International Journal of Molecular Sciences ◽

10.3390/ijms20010093 ◽

2018 ◽

Vol 20 (1) ◽

pp. 93

Author(s):

Jin Wang ◽

Feiyi Huang ◽

Xiong You ◽

Xilin Hou

Keyword(s):

Brassica Rapa ◽

Abiotic Stresses ◽

Quantitative Polymerase Chain Reaction ◽

Functional Characterization ◽

Regulation Mechanism ◽

Pak Choi ◽

Negative Effect ◽

Polymerase Chain ◽

Related Proteins

In plants, heptahelical proteins (HHPs) have been shown to respond to a variety of abiotic stresses, including cold stress. Up to the present, the regulation mechanism of HHP5 under low temperature stress remains unclear. In this study, BcHHP5 was isolated from Pak-choi (Brassica rapa ssp. chinensis cv. Suzhouqing). Sequence analysis and phylogenetic analysis indicated that BcHHP5 in Pak-choi is similar to AtHHP5 in Arabidopsis thaliana. Structure analysis showed that the structure of the BcHHP5 protein is relatively stable and highly conservative. Subcellular localization indicated that BcHHP5 was localized on the cell membrane and nuclear membrane. Furthermore, real-time quantitative polymerase chain reaction (RT-qPCR) analysis showed that BcHHP5 was induced to express by cold and other abiotic stresses. In Pak-choi, BcHHP5-silenced assay, inhibiting the action of endogenous BcHHP5, indicated that BcHHP5-silenced might have a negative effect on cold tolerance, which was further confirmed. All of these results indicate that BcHHP5 might play a role in abiotic response. This work can serve as a reference for the functional analysis of other cold-related proteins from Pak-choi in the future.

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