Rational Design of Polyamine-Based Cryogels for Metal Ion Sorption

Here we report the method of fabrication of supermacroporous monolith sorbents (cryogels) via covalent cross-linking of polyallylamine (PAA) with diglycidyl ether of 1,4-butandiol. Using comparative analysis of the permeability and sorption performance of the obtained PAA cryogels and earlier developed polyethyleneimine (PEI) cryogels, we have demonstrated the advantages and disadvantages of these polymers as sorbents of heavy metal ions (Cu(II), Zn(II), Cd(II), and Ni(II)) in fixed-bed applications and as supermacroporous matrices for the fabrication of composite cryogels containing copper ferrocyanide (CuFCN) for cesium ion sorption. Applying the rate constant distribution (RCD) model to the kinetic curves of Cu(II) ion sorption on PAA and PEI cryogels, we have elucidated the difference in sorption/desorption rates and affinity constants of these materials and showed that physical sorption contributed to the Cu(II) uptake by PAA, but not to that by PEI cryogels. It was shown that PAA cryogels had significantly higher selectivity for Cu(II) sorption in the presence of Zn(II) and Cd(II) ions in comparison with that of PEI cryogels, while irreversible sorption of Co(II) ions by PEI can be used for the separation of Ni(II) and Co(II) ions. Using IR and Mössbauer spectroscopy, we have demonstrated that strong complexation of Cu(II) ions with PEI significantly affects the in situ formation of Cu(II) ferrocyanide nanosorbents leading to their inefficiency for Cs+ ions selective uptake, whereas PAA cryogel was applicable for the fabrication of efficient monolith composites via the in situ formation of CuFCN or loading of ex situ formed CuFCN colloids.

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Rational Design and In-situ Formation of Nickel–Cobalt Nitride Multi-core/Hollow N-doped Carbon Shell Anode for Li-ion Batteries

Chemical Engineering Journal ◽

10.1016/j.cej.2021.129630 ◽

2021 ◽

pp. 129630

Author(s):

Bong Kyun Kang ◽

Yoo Jung Choi ◽

Hyung Wook Choi ◽

Seok Bin Kwon ◽

Suji Kim ◽

...

Keyword(s):

Rational Design ◽

Carbon Shell ◽

Li Ion Batteries ◽

Nickel Cobalt ◽

Li Ion ◽

In Situ Formation

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Collecting eco-evolutionary data in the dark: Impediments to subterranean research and how to overcome them

10.32942/osf.io/u5z3e ◽

2020 ◽

Author(s):

Stefano Mammola ◽

Enrico Lunghi ◽

Helena Bilandžija ◽

Pedro Cardoso ◽

Volker Grimm ◽

...

Keyword(s):

Model Systems ◽

Ex Situ ◽

Model Organisms ◽

Physiological Tolerance ◽

Advantages And Disadvantages ◽

General Scientific ◽

Experimental Model Systems ◽

Scientific Questions ◽

Subterranean Species

(1) Caves and other subterranean habitats fulfill the requirements of experimental model systems to address general questions in ecology and evolution. Yet, the harsh working conditions of these environments and the uniqueness of the subterranean organisms have challenged most attempts to pursuit standardized research(2) Two main obstacles have synergistically hampered previous attempts. First, there is a habitat impediment related to the objective difficulties of exploring subterranean habitats and our inability to access the network of fissures that represent the elective habitat for the so-called “cave species.” Second, there is a biological impediment illustrated by the rarity of most subterranean species and their low physiological tolerance, often limiting sample size and complicating lab experiments.(3) We explore the advantages and disadvantages of four general experimental setups (in-situ, quasi in-situ, ex-situ, and in-silico) in the light of habitat and biological impediments. We also discuss the potential of indirect approaches to research. Furthermore, using bibliometric data, we provide a quantitative overview of the model organisms that scientists have exploited in the study of subterranean life.(4) Our over-arching goal is to promote caves as model systems where one can perform standardised scientific research. This is important not only to achieve an in-depth understanding of the functioning of subterranean ecosystems but also to fully exploit their long-discussed potential in addressing general scientific questions with implications beyond the boundaries of this discipline.

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Soil Bioremediation: Overview of Technologies and Trends

Energies ◽

10.3390/en13184664 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4664

Author(s):

Israel Gonçalves Sales da Silva ◽

Fabíola Carolina Gomes de Almeida ◽

Nathália Maria Padilha da Rocha e Silva ◽

Alessandro Alberto Casazza ◽

Attilio Converti ◽

...

Keyword(s):

Contaminated Soils ◽

Petroleum Hydrocarbons ◽

Ex Situ ◽

Soil Bioremediation ◽

Application Of Surfactants ◽

Agricultural Pesticides ◽

Advantages And Disadvantages ◽

Microbiological Characteristics ◽

Extent Of Damage

Petroleum hydrocarbons, heavy metals and agricultural pesticides have mutagenic, carcinogenic, immunotoxic and teratogenic effects and cause drastic changes in soil physicochemical and microbiological characteristics, thereby representing a serious danger to health and environment. Therefore, soil pollution urgently requires the application of a series of physicochemical and biological techniques and treatments to minimize the extent of damage. Among them, bioremediation has been shown to be an alternative that can offer an economically viable way to restore polluted areas. Due to the difficulty in choosing the best bioremediation technique for each type of pollutant and the paucity of literature on soil bioremediation enhanced by the use of specific additives, we reviewed the main in situ and ex situ methods, their current properties and applications. The first section discusses the characteristics of each class of pollutants in detail, while the second section presents current bioremediation technologies and their main uses, followed by a comparative analysis showing their respective advantages and disadvantages. Finally, we address the application of surfactants and biosurfactants as well as the main trends in the bioremediation of contaminated soils.

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Computer-Controlled Polishing System For Preparing Multiple Pre-FIB TEM Specimens

Microscopy Today ◽

10.1017/s1551929500061952 ◽

2007 ◽

Vol 15 (6) ◽

pp. 38-39

Author(s):

D. J. MacMahon ◽

E. Raz-Moyal

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Product Yield ◽

Interface Layer ◽

Ex Situ ◽

Advantages And Disadvantages ◽

Transmission Electron ◽

Invaluable Tool ◽

Electron Microscopes

Semiconductor manufacturers are increasingly turning to Transmission Electron Microscopes (TEMs) to monitor product yield and process control, analyze defects, and investigate interface layer morphology. To prepare TEM specimens, Focused Ion Beam (FIB) technology is an invaluable tool, yielding a standard milled TEM lamella approximately 15 μm wide, 5 μm deep and ~100 nm thick. Several techniques have been developed to extract these tiny objects from a large wafer and view it in the TEM. These techniques, including ex-situ lift-out, H-bar, and in-situ lift-out, have different advantages and disadvantages, but all require painstaking preparation of one specimen at a time.

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Origin of the Difference in the Resistivity of As-Grown Focused-Ion- and Focused-Electron-Beam-Induced Pt Nanodeposits

Journal of Nanomaterials ◽

10.1155/2009/936863 ◽

2009 ◽

Vol 2009 ◽

pp. 1-11 ◽

Cited By ~ 53

Author(s):

J. M. De Teresa ◽

R. Córdoba ◽

A. Fernández-Pacheco ◽

O. Montero ◽

P. Strichovanec ◽

...

Keyword(s):

Voltage Dependence ◽

Ion Beam ◽

Carbon Matrix ◽

Ex Situ ◽

Semiconducting Materials ◽

Dual Beam ◽

Transmission Electron ◽

The Difference ◽

Main Component

We study the origin of the strong difference in the resistivity of focused-electron- and focused-Ga-ion-beam-induced deposition (FEBID and FIBID, resp.) of Pt performed in a dual beam equipment using(CH3)3Pt(CpCH3)as the precursor gas. We have performed in-situ and ex-situ resistance measurements in both types of nanodeposits, finding that the resistivity of Pt by FEBID is typically four orders of magnitude higher than Pt by FIBID. In the case of Pt by FEBID, the current-versus-voltage dependence is nonlinear and the resistance-versus-temperature behavior is strongly semiconducting, whereas Pt by FIBID shows linear current-versus-voltage dependence and only slight temperature dependence. The microstructure, as investigated by high-resolution transmission electron microscopy, consists in all cases of Pt single crystals with size about 3 nm embedded in an amorphous carbonaceous matrix. Due to the semiconducting character of the carbon matrix, which is the main component of the deposit, we propose that the transport results can be mapped onto those obtained in semiconducting materials with different degrees of doping. The different transport properties of Pt by FEBID and FIBID are attributed to the higher doping level in the case of FIBID, as given by composition measurements obtained with energy-dispersive X-ray microanalysis.

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Development of anti-microbial jute fabrics via in situ formation of cellulose–tannic acid–metal ion complex

Carbohydrate Polymers ◽

10.1016/j.carbpol.2009.10.019 ◽

2010 ◽

Vol 79 (4) ◽

pp. 890-897 ◽

Cited By ~ 20

Author(s):

Asha Higazy ◽

Mohamed Hashem ◽

Ali ElShafei ◽

Nihal Shaker ◽

Marwa Abdel Hady

Keyword(s):

Tannic Acid ◽

Metal Ion ◽

In Situ Formation ◽

Jute Fabrics ◽

Metal Ion Complex

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Investigation of In-Situ and Ex-Situ Catalytic Pyrolysis Upgrading of Pine Using Thermo-Gravimetric Analysis and a Fixed-Bed Reactor System

Journal of Biobased Materials and Bioenergy ◽

10.1166/jbmb.2017.1689 ◽

2017 ◽

Vol 11 (5) ◽

pp. 400-413 ◽

Cited By ~ 2

Author(s):

Yunwu Zheng ◽

Fei Wang ◽

Xiaoqing Yang ◽

Can Liu ◽

Yuanbo Huang ◽

...

Keyword(s):

Catalytic Pyrolysis ◽

Thermo Gravimetric Analysis ◽

Fixed Bed ◽

Reactor System ◽

Fixed Bed Reactor ◽

Ex Situ ◽

Gravimetric Analysis ◽

Thermo Gravimetric

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Electromigration Damage in Conductor Lines: Recent Progress in Microscopic Observation and Mechanistic Modelling

MRS Proceedings ◽

10.1557/proc-338-397 ◽

1994 ◽

Vol 338 ◽

Cited By ~ 19

Author(s):

E. Arzt ◽

O. Kraft ◽

U.E. MÖckl

Keyword(s):

Rational Design ◽

Recent Progress ◽

Ex Situ ◽

Mechanistic Modelling ◽

Stress Effects ◽

Recent Developments ◽

Current Densities ◽

Damage Map ◽

Shape Changes

ABSTRACTIn this paper an overview of recent developments in understanding electromigration damage mechanisms is given. Based on our detailed studies, both ex-situ and in-situ, of damage in unpassivated near-bamboo lines, we develop a theoretical electromigration damage map. It explains why “slit-like” failure becomes predominant for narrow lines and low current densities. The mechanism of slit formation is discussed in the light of new analytical and numerical simulations of pore shape changes, which take stress effects into account. Possible implications for the rational design of improved metallization alloys are suggested.

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