Quercus sichourensis and Pinus squamata fruit for the first time in ex situ cultivation

ABSTRACTThe lead based superconductor Pb2Sr2Y0.5Ca0.5Cu3O8+δ is a most complex material. If any oxygen is present in the PbO-CuOδ-PbO sandwich layer (i.e. if δ>0) the superconductivity deteriorates. This is also a most difficult material to grow not only because of the large number of cation stoichiometries which have to be precisely balanced but also because of the tendency for multiple phases to form. Pulsed laser deposition (PLD) has been applied to prepare thin films of the 2213-phase on MgO (100) single crystal substrates at low temperature (300°C) in low oxidizing atmospheres. A basic set of ex-situ growth conditions has been determined which produce for the first time good quality films of this material as characterized by DC resistivity using the Van der Pauw method, as well as EDX and XRD. The layers are reasonably c-axis oriented and display a superconducting onset transition temperature of 79K and zero resistance at 65K after subsequent annealing in a nitrogen ambient.

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Importance of the pyrolysis for microstructure and superconducting properties of CSD-grown GdBa2Cu3O7−x-HfO2 nanocomposite films by the ex-situ approach

Scientific Reports ◽

10.1038/s41598-020-75587-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Pablo Cayado ◽

Hannes Rijckaert ◽

Els Bruneel ◽

Manuela Erbe ◽

Jens Hänisch ◽

...

Keyword(s):

Processing Parameters ◽

Nanocomposite Films ◽

Ex Situ ◽

Superconducting Properties ◽

Critical Temperatures ◽

Solution Deposition ◽

Nanoparticle Distribution ◽

Current Densities ◽

First Time ◽

Lower Heating

Abstract For the first time, GdBa2Cu3O7−x nanocomposites were prepared by chemical solution deposition following the ex-situ approach. In particular, ~ 220 nm GdBa2Cu3O7−x-HfO2 (GdBCO-HfO2) nanocomposite films were fabricated starting from a colloidal solution of 5 mol% HfO2 nanoparticles. Hereby, one of the main challenges is to avoid the accumulation of the nanoparticles at the substrate interface during the pyrolysis, which would later prevent the epitaxial nucleation of the GdBCO grains. Therefore, the effect of pyrolysis processing parameters such as heating ramp and temperature on the homogeneity of the nanoparticle distribution has been investigated. By increasing the heating ramp to 300 °C/h and decreasing the final temperature to 300 °C, a more homogenous nanoparticle distribution was achieved. This translates into improved superconducting properties of the grown films reaching critical temperatures (Tc) of 94.5 K and self-field critical current densities ($${J}_{\mathrm{c}}^{\mathrm{sf}}$$ J c sf ) at 77 K of 2.1 MA/cm2 with respect to films pyrolyzed at higher temperatures or lower heating ramps.

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Novel synthesis and electrochemical investigations of ZnO/C composites for lithium-ion batteries

Journal of Materials Science ◽

10.1007/s10853-021-06125-4 ◽

2021 ◽

Author(s):

E. Thauer ◽

G. S. Zakharova ◽

E. I. Andreikov ◽

V. Adam ◽

S. A. Wegener ◽

...

Keyword(s):

Lithium Ion Batteries ◽

Electronic Conductivity ◽

Lithium Ion ◽

Nitrogen Atmosphere ◽

Ex Situ ◽

Ion Diffusion ◽

Storage Mechanism ◽

Treatment Conditions ◽

One Step ◽

First Time

AbstractFor the first time, ZnO/C composites were synthesized using zinc glycerolate as a precursor through one-step calcination under a nitrogen atmosphere. The effect of the heat treatment conditions on the structure, composition, morphology as well as on the electrochemical properties regarding application in lithium-ion batteries are investigated. The products obtained by calcination of the precursor in nitrogen at 400—800 °C consist of zinc oxide nanoparticles and amorphous carbon that is in-situ generated from organic components of the glycerolate precursor. When used as anode material for lithium-ion batteries, the as-prepared ZnO/C composite synthesized at a calcination temperature of 700 °C delivers initial discharge and charge capacities of 1061 and 671 mAh g−1 at a current rate of 100 mA g−1 and hence 1.5 times more than bare ZnO, which reaches only 749/439 mAh g−1. The native carbon improves the conductivity, allowing efficient electronic conductivity and Li-ion diffusion. By means of ex-situ XRD studies a two-step storage mechanism is proven.

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Novel catalytic and mechanistic studies on wastewater denitrification with hydrogen

Water Science & Technology ◽

10.2166/wst.2013.781 ◽

2013 ◽

Vol 69 (3) ◽

pp. 680-686 ◽

Cited By ~ 7

Author(s):

C. P. Theologides ◽

G. G. Olympiou ◽

P. G. Savva ◽

N. A. Pantelidou ◽

B. K. Constantinou ◽

...

Keyword(s):

Active Sites ◽

Ex Situ ◽

Mechanistic Study ◽

Feed Composition ◽

Water Media ◽

Active Intermediate ◽

Cu Catalysts ◽

Diffuse Reflectance Infrared ◽

Isotopic Transient Kinetic Analysis ◽

First Time

The present work reports up-to-date information regarding the reaction mechanism of the catalytic hydrogenation of nitrates in water media. In the present mechanistic study, an attempt is made, for the first time, to elucidate the crucial role of several catalysts and reaction parameters in the mechanism of the NO3−/H2 reaction. Steady-state isotopic transient kinetic analysis (SSITKA) experiments coupled with ex situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) were performed on supported Pd-Cu catalysts for the NO3−/H2 and NO3−/H2/O2 reactions. The latter experiments revealed that the formation and surface coverage of various adsorbed active intermediate N-species on the support or Pd/Cu metal surface is significantly favored in the presence of TiO2 in the support mixture and in the presence of oxygen in the reaction's gaseous feed stream. The differences in the reactivity of these adsorbed N-species, found in the present work, adequately explain the large effect of the chemical composition of the support and the gas feed composition on catalyst behaviour (activity and selectivity). The present study leads to solid mechanistic evidence concerning the presence of a hydrogen spillover process from the metal to the support. Moreover, this study shows that Cu clusters are active sites for the reduction of nitrates to nitrites.

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The reduction of doxorubicin at a mercury electrode and monitoring its interaction with DNA using constant current chronopotentiometry

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc2009512 ◽

2009 ◽

Vol 74 (11-12) ◽

pp. 1727-1738 ◽

Cited By ~ 10

Author(s):

Jan Vacek ◽

Luděk Havran ◽

Miroslav Fojta

Keyword(s):

Double Helix ◽

Mercury Electrode ◽

Electrode Reaction ◽

Ex Situ ◽

Constant Current ◽

Adsorbed State ◽

Electrode Processes ◽

Dna Double Helix ◽

First Time

In this report, voltammetry with linear scan and chronopotentiometric stripping (CPS) with constant current were used for the analysis of doxorubicin (DOX) at a hanging mercury drop electrode (HMDE). CPS was used for the study of DOX in situ electrochemical reduction in adsorbed state and for ex situ (adsorptive transfer) analysis of the drug. For the first time, CPS was used to study the reversible reduction of the DOX quinine moiety at –0.45 V (vs Ag|AgCl|3 M KCl) as well as electrode processes giving rise to an irreversible signal around –1.45 V at the HMDE in 0.2 M acetate or Britton–Robinson buffers at different pH values. The dependence of the latter signal on pH revealed involvement of protonation equilibria; however, neither CV nor CPS data confirmed the catalytic character of the electrode reaction previously suggested by other authors. The CPS method was also applied to monitor the DOX interaction with double- (ds) and single-stranded (ss) DNA. In the presence of dsDNA, more pronounced changes in DOX signal intensity were observed, in agreement with a strong intercalation of the DOX redox centre into the DNA double helix.

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The Composition-Tunable Polydiacetylenic Complex Films: Conformational Change upon Thermal Stimulation and Preferential Interaction with Specific Small Molecules

Journal of Nanomaterials ◽

10.1155/2017/5983106 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7

Author(s):

Chao Wang ◽

Jin Hyuk Park ◽

Songwen Tan ◽

Chunzhi Cui ◽

Jing-Yi Jin ◽

...

Keyword(s):

Small Molecules ◽

Conformational Change ◽

Conformational Changes ◽

Optoelectronic Devices ◽

Thermal Stimulation ◽

Ex Situ ◽

Molar Ratio ◽

Ftir Analysis ◽

Acid Base ◽

First Time

Polydiacetylenic complex films were prepared using 10,12-pentacosadiynoic acid (PCDA) and para-xylenediamine (pXDA) upon acid-base interactions. The thermochromatic reversibility of the complex films was modulated by changing the mixed molar ratio (3 : 1, 2 : 1, and 1 : 1) of the two molecules. The corresponding conformational changes of the complex films were studied by ex situ FTIR analysis upon thermal stimulation for the first time. In addition, the binding specificities of α-, β-, and γ-cyclodextrins (CDs) with the films were studied, where the α-CDs can induce stronger red fluorescent emission of the films. These fundamental results may be useful for platforms that use these polydiacetylenic complex films as optoelectronic devices or chemical/biological sensors.

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Chemical Constituents and Protection of Biodiversity of Corypha taliera Roxb., a Critically Endangered Plant of Bangladesh

Bangladesh Pharmaceutical Journal ◽

10.3329/bpj.v20i2.37888 ◽

2018 ◽

Vol 20 (2) ◽

pp. 213-220

Author(s):

Akhtaruzzaman Chowdhury ◽

Md Ashraful Alam ◽

Md Shafiullah Shajib ◽

Mohammad Abdullah Al Mansur ◽

Mohammad A Rashid

Keyword(s):

Spectroscopic Analysis ◽

Methanol Extract ◽

Chemical Constituents ◽

Pharmaceutical Journal ◽

Critically Endangered ◽

Ex Situ ◽

Endangered Plant ◽

Separation And Purification ◽

First Time ◽

Mature Seeds

This article focuses on the chemical constituents and protection of biodiversity through plantation of saplings of Corypha taliera Roxb., a critically endangered plant of Bangladesh. Until 2010, the tree in the campus of University of Dhaka, used to be considered as the lone surviving species in the world in nature. Succesive chromatographic separation and purification of the methanol extract of air dried flowers of C. taliera provided β-sitosterol (1), β-amyrin (2), and betulinic acid (3) for the first time from its flowers. The structures of these purified compounds were established by extensive spectroscopic analysis and comparison of spectral data with published values as well as co-TLC with authentic samples. On the other hand, 500 mature seeds were sown in seed beds in the Medicinal Plant Garden of Faculty of Pharmacy, University of Dhaka, and Azimpur Government Officers' Quarter premises. After 40 days, the root was first seen to grow in its habitat and 85 days later the shoot developed up to 2.5 cm in height. The rate of germination was found to be 89-93%. The produced saplings were later on planted in different places of Bangladesh for conservation of the plant and protection of biodiversity by ex situ arrangement.Bangladesh Pharmaceutical Journal 20(2): 213-220, 2017

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Linnaea borealis L. var. borealis—In Vitro Cultures and Phytochemical Screening as a Dual Strategy for Its Ex Situ Conservation and a Source of Bioactive Compounds of the Rare Species

Molecules ◽

10.3390/molecules26226823 ◽

2021 ◽

Vol 26 (22) ◽

pp. 6823

Author(s):

Barbara Thiem ◽

Dariusz Kruszka ◽

Natalia Turowska ◽

Elwira Sliwinska ◽

Viktor Berge ◽

...

Keyword(s):

Plant Biomass ◽

Shoot Culture ◽

Growth Index ◽

In Vitro Cultures ◽

Raw Material ◽

Ex Situ ◽

Shoot Cultures ◽

Triterpenoid Saponins ◽

First Time

Linnaea borealis L. (Twinflower)—a dwarf shrub in the Linnaeeae tribe of Caprifoliaceae family—is distributed across the Northern Hemisphere. By means of this study, a reliable protocol for efficient micropropagation of uniform L. borealis L. var. borealis plantlets has been provided for the first time; callus culture was also established. Different initial explants, types of cultures, media systems, and plant growth regulators in Murashige and Skoog (MS) media were tested. Agitated shoot cultures in the liquid media turned out to be the best system for the production of sustainable plant biomass. After stabilization of the callus lines, the highest growth index (c.a. 526%) was gained for callus maintained on MS enriched with picloram. TLC and UHPLC-HESI-HRMS analysis confirmed the presence of phenolic acids and flavonoids, and for the first time, the presence of iridoids and triterpenoid saponins in this species. Multiplication of L. borealis shoot culture provides renewable raw material, allowing for the assessment of the phytochemical profile, and, in the future, for the quantitative analyses and the studies of the biological activity of extracts, fractions, or isolated compounds. This is the first report on in vitro cultures of traditionally used L. borealis rare taxon and its biosynthetic potential.

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Detection of Parasites and Parasitic Infections of Free-Ranging Wildlife on a Game Ranch in Zambia: A Challenge for Disease Control

Journal of Parasitology Research ◽

10.1155/2012/296475 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Hetron Mweemba Munang'andu ◽

Victor M. Siamudaala ◽

Musso Munyeme ◽

King Shimumbo Nalubamba

Keyword(s):

Vital Role ◽

Control Measures ◽

Ex Situ ◽

Parasitic Infections ◽

Susceptible Animal ◽

Lack Of Information ◽

Behavioural Patterns ◽

Kafue Lechwe ◽

Free Ranging ◽

First Time

Ex-situconservancies are expanding alternatives to livestock production in Zambia albeit the lack of information on circulating infectious parasites from wildlife. Therefore, 12 wildlife species were examined on a game ranch were all species were found to be infected byRhipecephalusspp. Haemoparasite infections were estimated at 7.37% (n=95) withBabesiaspp. detected in bushbuck (Tragelaphus scriptus);Anaplasma marginalein impala (Aepyceros melampus) and puku (Kobus vardonii) for the first time in Zambia. The majority of worm species isolated from bovids were not detected in equids and,vice versa. Our findings intimate ecological and behavioural patterns of some animals as deterministic to exposure. Kafue lechwe (Kobus leche kafuensis) had the widest range of worm species with more infected organs than other animals suggesting their semi aquatic nature contributory to prolonged worm exposure compared to other animals. On the other hand, Kafue lechwe had the least tick infections attributable more to shorter attachment periods as they spend prolonged periods submerged in water. Our findings indicate the vital role that wildlife plays in the epidemiology of parasitic diseases. To reduce the infection burden, control measures should be focused on reducing transmission to highly susceptible animal species as described herein.

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Chronic wasting associated with Chlamydia pneumoniae in three ex situ breeding facilities for tropical frogs

Antonie van Leeuwenhoek ◽

10.1007/s10482-020-01483-6 ◽

2020 ◽

Vol 113 (12) ◽

pp. 2139-2154

Author(s):

Tobias Eisenberg ◽

Ahmad Fawzy ◽

Ute Kaim ◽

Anne Nesseler ◽

Karin Riße ◽

...

Keyword(s):

Chlamydia Pneumoniae ◽

Clinical Signs ◽

Amphibian Decline ◽

Mass Mortality ◽

Ex Situ ◽

Amphibian Conservation ◽

Treatment Regimens ◽

Predominant Species ◽

Frog Species ◽

First Time

AbstractA number of different Chlamydia spp. have been detected in the class Amphibia with C. pneumoniae being the predominant species involved. Chlamydiae have been linked to mass mortality events, thereby representing significant pathogens that deserve attention with respect to worldwide amphibian decline. We here present six cases of chlamydiosis and asymptomatic chlamydial infections in different frog species from three ex situ amphibian conservation facilities. Clinical signs predominantly characterised by regurgitation, chronic wasting, lethargy and suspended breeding were associated with C. pneumoniae infection. Despite various treatment regimens, it was not possible to clear infections. However, intra vitam diagnostics succeeded from skin, faeces and urine for the first time.

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