scholarly journals Environmental Nanoparticles Interactions with Plants: Morphological, Physiological, and Genotoxic Aspects

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
C. Remédios ◽  
F. Rosário ◽  
V. Bastos
Keyword(s):  
Physicochemical Properties ◽  
Surface Area ◽  
Emerging Contaminants ◽  
Materials Science ◽  
Environmental Catalysis ◽  
Growth Area ◽  
In The Beginning ◽  
Reliable Methods ◽  
Different Levels ◽  
Scientific Growth

Nanoparticles (NPs) are characterized by their small size (less than 100 nm) and large surface area, which confer specific physicochemical properties as strength, electrical, and optical features. NPs can be derived from natural or anthropic sources, such as engineered or unwanted/incidental NPs. The composition, dimension, and morphology of engineered NPs enable their use in a variety of areas, such as electronic, biomedical, pharmaceutical, cosmetic, energy, environmental, catalysis, and materials science. As nanotechnology is an innovative and scientific growth area with an exponential production, more information is needed concerning the impacts of these nanomaterials (NMs) in the environment and, particularly, in animals/humans health and in plants performance. So, research on NPs as emerging contaminants is therefore a new field in environmental health. This minireview describes, briefly, the NPs characterization and their occurrence in the environment stating air, water, and soil. Finally, particular emphasis is given to the interaction of NPs with plants at different levels: morphology, physiology, and genotoxicity. By analyzing this compiled information, it is evident that research on NPs phytotoxicity is in the beginning, and more comprehensive studies are needed not only on NPs cytotoxicity and genotoxicity but also on the best and the most reliable methods of assessing NPs toxicity.

Preparation and characterisation of vanadium pentoxide supported rhodium catalyst

1988 ◽  
Vol 46 ◽  
pp. 946-947
Author(s):  
A. Legrouri
Keyword(s):  
Aqueous Solution ◽  
Thermal Decomposition ◽  
Physicochemical Properties ◽  
Surface Area ◽  
Vanadium Pentoxide ◽  
High Purity ◽  
Gas Adsorption ◽  
Rhodium Catalyst ◽  
Optical Methods ◽  
Reducible Oxides

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.

scholarly journals Effect of Low Zeolite Doses on Plants and Soil Physicochemical Properties

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2617
Author(s):  
Alicja Szatanik-Kloc ◽  
Justyna Szerement ◽  
Agnieszka Adamczuk ◽  
Grzegorz Józefaciuk
Keyword(s):  
Plant Growth ◽  
Physicochemical Properties ◽  
Cation Exchange ◽  
Surface Area ◽  
Cation Exchange Capacity ◽  
N Fertilization ◽  
Exchange Capacity ◽  
First Year ◽  
Soil Physicochemical Properties ◽  
Water Holding

Thousands of tons of zeolitic materials are used yearly as soil conditioners and components of slow-release fertilizers. A positive influence of application of zeolites on plant growth has been frequently observed. Because zeolites have extremely large cation exchange capacity, surface area, porosity and water holding capacity, a paradigm has aroused that increasing plant growth is caused by a long-lasting improvement of soil physicochemical properties by zeolites. In the first year of our field experiment performed on a poor soil with zeolite rates from 1 to 8 t/ha and N fertilization, an increase in spring wheat yield was observed. Any effect on soil cation exchange capacity (CEC), surface area (S), pH-dependent surface charge (Qv), mesoporosity, water holding capacity and plant available water (PAW) was noted. This positive effect of zeolite on plants could be due to extra nutrients supplied by the mineral (primarily potassium—1 ton of the studied zeolite contained around 15 kg of exchangeable potassium). In the second year of the experiment (NPK treatment on previously zeolitized soil), the zeolite presence did not impact plant yield. No long-term effect of the zeolite on plants was observed in the third year after soil zeolitization, when, as in the first year, only N fertilization was applied. That there were no significant changes in the above-mentioned physicochemical properties of the field soil after the addition of zeolite was most likely due to high dilution of the mineral in the soil (8 t/ha zeolite is only ~0.35% of the soil mass in the root zone). To determine how much zeolite is needed to improve soil physicochemical properties, much higher zeolite rates than those applied in the field were studied in the laboratory. The latter studies showed that CEC and S increased proportionally to the zeolite percentage in the soil. The Qv of the zeolite was lower than that of the soil, so a decrease in soil variable charge was observed due to zeolite addition. Surprisingly, a slight increase in PAW, even at the largest zeolite dose (from 9.5% for the control soil to 13% for a mixture of 40 g zeolite and 100 g soil), was observed. It resulted from small alterations of the soil macrostructure: although the input of small zeolite pores was seen in pore size distributions, the larger pores responsible for the storage of PAW were almost not affected by the zeolite addition.

Solomon and Saturn I, 89 a, “prologa prim”: An Exercise in Monastic Reading Practice

2020 ◽  
Vol 138 (4) ◽  
pp. 618-648
Author(s):  
Rachel A. Burns
Keyword(s):  
Old English ◽  
Half Line ◽  
Lectio Divina ◽  
Reading Practice ◽  
John 1 ◽  
Grammatical Analysis ◽  
Subsequent Episode ◽  
In The Beginning ◽  
The Devil ◽  
Different Levels

AbstractThis article reassesses the grammatically problematic half-line prologa prima (l. 89a) in the Old English wisdom poem Solomon and Saturn I, and suggests that it ought to be emended to the grammatically viable reading of “prologa prim”. Line 89 a introduces a passage in which the words of the Pater Noster become anthropomorphised as warriors and attack the devil. I will argue that “prologa prim” is an exegetical exercise, informed by grammatical theory and liturgical practice, designed for an audience of monastic readers. This multivalent half-line offers different levels of meaning when read according to different permutations of language and metaphor, in a process analogous to the interpretation of scripture according to the influential model of fourfold exegesis. When read literally, as ‘the first of the initial letters’, “prologa prim” indicates the unfolding and time-bound process of reading. Previous scholars (Anlezark 2009; Anderson 1998) have noted the allusive references in line 89 a to Greek logos (‘word’) and Old English prim (‘first hour’, ‘Prime office’), but not their full significance. Through these allusions, the reader shifts from a literal reading to a spiritual and metaphorical reading of the half-line, achieving a diachronic perspective of the Pater Noster’s recitation across time, and finally an atemporal perspective, reading in line 89 a a paraphrase of John 1:1, “In the beginning was the Word”. In conjunction with the subsequent episode of the battle, line 89 a forms an exemplum of the monastic practice of lectio divina. This example of ‘monastic poetics’ (O’Camb 2014; Niles 2019) moves from grammatical analysis to a vision of the Word.

Characteristics of variably saturated granular bentonite after long-term storage at near-field relevant temperatures

Clay Minerals ◽  
2013 ◽  
Vol 48 (2) ◽  
pp. 343-361 ◽  
Author(s):  
M. Valter ◽  
M. Plötze
Keyword(s):  
Physicochemical Properties ◽  
Cation Exchange ◽  
Surface Area ◽  
Cation Exchange Capacity ◽  
Elevated Temperatures ◽  
Near Field ◽  
Exchange Capacity ◽  
Hydraulic Permeability ◽  
Cation Composition ◽  
Retention Capacity

AbstractBentonite is a potential material for use in the engineered barrier of radioactive waste repositories because of its low hydraulic permeability, self-sealing capability and retention capacity. It is expected that bentonite would react at the elevated temperatures accompanying the radioactive decay in the nuclear waste. The presented study was started in order to improve understanding of the coupled influence of temperature and (pore) water on the physicochemical and mineralogical properties of bentonite during thermal treatment under near-field relevant conditions. Granular Na-bentonite MX-80 was differently saturated (Sr = 1–0.05) and stored at different temperatures (50–150°C) in a closed system. Upon dismantling after different periods of time (3 to 18 months), mineralogical characteristics, cation exchange capacity and content of leachable cations, as well as physicochemical properties such as surface area and water adsorption were investigated.The results showed a high mineralogical stability. A slight conversion from the sodium to an earth alkali form of the bentonite was observed. However, considerable changes in the physicochemical properties of the bentonite were observed, particularly by treatment above the critical temperature of 120°C. The cation exchange capacity decreased during heating at 150°C by approximately. 10%. The specific surface area dropped by more than 50%. The water uptake capacity under free swelling conditions showed a slight tendency to lower values especially for samples heated for more than 12 months. The water vapour adsorption ability in contrast drops by 25% already within three months at T = 120°C. These changes are mostly related to the variations in the interlayer cation composition and to smectite aggregation processes. The observed alterations are rather subtle. However, temperatures ⩾ 120°C had a remarkable negative influence on different properties of MX-80.

Human Epididymis: Structural Pattern, Total Length and Inner Surface Area

2017 ◽  
Vol 84 (4) ◽  
pp. 215-217 ◽  
Author(s):  
Kalanghot P. Skandhan ◽  
Ashutosh Soni ◽  
Anantkumar Joshi ◽  
Kalanghot P.S. Avni ◽  
Bansi Dhar Gupta
Keyword(s):  
Surface Area ◽  
Structural Pattern ◽  
Single Tube ◽  
Human Epididymis ◽  
Total Length ◽  
Inner Surface ◽  
Dead Bodies ◽  
Different Levels

Introduction The organ epididymis is secured the name considering it functioned as an appendix to the testis; earlier testis was called as didymi. Regarding the length of human epididymis, several values are attributed by different authors. The present study was aimed to find out the pattern, total length and inner surface area of human epididymis. Materials and Methods The study was conducted by employing microsurgical procedures on five testes from unclaimed human dead bodies. Results Caput was formed by few tubes interconnecting at three levels. These tubes led to corpus, which in turn was having more number of tubes interconnecting at different levels. Tubules were many looking like a mesh. United tubes of corpus form the single tube to form cauda. Epididymis length was 30.48 cm. Inner surface area was 818.16 mm2. Conclusions Reported values of others seem to be a modified version from that of animals. Authors believe that organic revolutionary changes in man led to a reduction in the length of epididymis.

scholarly journals A comparison of methods to estimate harvest-induced damage to the soil using the example of a beech timber stand

2014 ◽  
Vol 75 (3) ◽  
pp. 245-251
Author(s):  
Dariusz Kulak
Keyword(s):  
Surface Area ◽  
Soil Condition ◽  
Visual Assessment ◽  
Field Trials ◽  
Comparison Of Methods ◽  
Farm Tractor ◽  
Damage Indicators ◽  
Soil Disturbances ◽  
Different Order ◽  
Different Levels

Abstract The study determines the extent of soil disturbances occurring during mechanised harvesting operations in a beech timber stand and investigates whether applying different research methods can be used to classify, in a comparable way, forest areas with different levels of soil damage. In the analysed stand, felling and on-side processing were conducted with chainsaws, while extraction - using an farm tractor. After the completion of logging operations, visible soil disturbances on each sample plot were measured, including surface area, volume and depth, and the value of five most common indicators of soil damage was calculated. The share of disturbed surface area, the volume of soil disturbances and different soil damage indicators allowed sample plots to be arranged in the same way according to increasing levels of soil damage occurring during harvesting. A different order was observed only in relation to the depth of the ruts formed. The similarity of the applied measures and classifications of soil disturbances indicates that all of the methods can be applied to make simple comparisons of the degree of soil damage. Because field trials are easy to perform, soil damage indicators based on a visual assessment of soil condition, without the need to take measurements, are worth recommending at first. A fuller picture of the level and nature of detected soil damage, however, can be obtained by taking into account the depth of the disturbance.

scholarly journals Emerging contaminants : a tutorial mini-review

2013 ◽  
Vol 14 (1) ◽  
pp. 72-79 ◽  
Keyword(s):  
Emerging Contaminants ◽  
Residue Analysis ◽  
Sewage Treatment ◽  
Emerging Pollutants ◽  
Environmental Issue ◽  
Published Data ◽  
Aquatic Environments ◽  
Contamination Source ◽  
Toxicological Effects ◽  
Reliable Methods

Nowadays, the scientific community has focused and prioritised research on “emerging pollutants”. The term “emerging pollutants” stands for the substances that are released in the environment for which currently no regulations are established for their environmental monitoring. Their occurrence is reported worldwide in a range of aquatic environments, such as lakes, rivers, freshwater catchments, estuaries, reservoirs and marine waters. Nevertheless, due to their large number (ranging in an order of thousands), only few of these compounds are toxicologically evaluated. Published data concerning occurrence and potential toxicological effects is limited. The contamination source of the aquatic environment is mainly the effluents from the sewage treatment plants (STPs). Reliable methods are available for residue analysis of these pollutants down to low ng L-1 levels. However, an urgent need is highlighted for the investigation (primarily in environmental media and following in biological ones) of the toxicity and transformation pathways of all emerging pollutants. The aims of this mini-review are to briefly present: (a) the major classes of emerging pollutants; (b) the reasons why these substances constitute an environmental issue; and (c) developments and applications of environmental analysis in this field.

Organic- or Inorganic-based Nanomaterials: Opportunities and Challenges in the Selection for Biomedicine

2021 ◽  
Vol 27 ◽  
Author(s):  
Ranjith Kankala
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Surface Area ◽  
Therapeutic Strategies ◽  
Lessons Learned ◽  
Clinical Translation ◽  
Significant Progress ◽  
Morphological Attributes ◽  
The Past ◽  
Selection For

: Since the inception of nanotechnology, several efforts have been dedicated to fabricating diverse nanodevices with exceptional performance. These innovative constructs have been applied in medicine due to their tailorable physicochemical properties (chemical composition, optical activity, spectra, and charge) and morphological attributes (size, shape, and surface area). Moreover, these versatile nanomedicines could promisingly offer better performance over the conventional therapeutic strategies. Broadly speaking, in terms of chemical composition, nanobiomaterials are classified into two predominant categories of organic and inorganic-based components. Despite their success and enormous versatile advancements in the past two decades, the significant progress towards clinical translation has been hampered by their corresponding intrinsic limitations. In this perspective, we give a brief overview of these organic- and inorganic-based materials, highlighting opportunities and challenges towards their utilization in medicine. Finally, we provide an interesting outlook in lessons learned and looking forward to developing these materials, emphasizing their scope towards clinical translation.

scholarly journals Impact of Biochar on Physicochemical Properties of Haplic Luvisol Soil under Different Land Use: A Plot Experiment

Agronomy ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 531 ◽  
Author(s):  
Marta Cybulak ◽  
Zofia Sokołowska ◽  
Patrycja Boguta
Keyword(s):  
Physicochemical Properties ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Physicochemical Characterization ◽  
Organic Carbon Content ◽  
Limited Information ◽  
Opposite Trend ◽  
And Function ◽  
Positive Effect

There is limited information regarding the effect of biochar (BioC) on improving the fertility of degraded soils (fallow and grassland), particularly with respect to changes with time. The objective of the study was to evaluate, in a three-year field experiment, the influence of BioC on the physicochemical properties of Haplic Luvisol. BioC, obtained via wood waste pyrolysis at 650 °C, was applied to the soil of subplots under fallow and grassland at rates of 0, 1, 2, and 3 kg·m−2. Soil samples were collected eight times, from 2013 to 2015. Physicochemical characterization was performed for soil and BioC by analyzing density, pH, surface charge, as well as ash and organic carbon content. BioC’s influence on the physicochemical properties of degraded soils was determined by analyzing the changes in pH, specific surface area, radius, and volume of the micropore. The addition of BioC affected analyzed soils to varying degrees. In the case of the fallow, a positive effect on changes in these parameters was observed, particularly at the highest biochar dose and for the last year of the experiment. However, for the grassland, in most cases we observed the opposite trend—for example, pH and specific surface area values decreased with increasing biochar dose. We believe that it is necessary to examine how BioC affects sorption properties of organic matter of fallow and grassland soils, as well as the BioC’s influence on humic acids of these soils as a function on BioC dose and function of time.

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