Calculation of the working element for layer-by-layer soil-free tillage

The paper proves the scheme and proposes a technique of engineering calculation of the working element for layer-by-layer soil-free tillage in conditions of insufficient moisture. Soil treatment causes significant changes in the volume ratio of the solid, liquid and gaseous phases influencing the chemical, physico-chemical and biological processes, accelerating or slowing down the rate of synthesis and destruction of organic matter. Soil cultivation creates favorable physical conditions for soil fertility. It continues to be one of the most important ways to control weeds, pests and diseases of crops. However, the use of known working elements for soil cultivation does not allow to intensify all the factors ensuring the increase and reproduction of effective fertility. The most effective way to achieve this can be the use of a working organ that decompresses the lower horizons, providing differential crumbling of soil layers, creating a mulch layer on the surface and increasing erosion resistance, i.e. layer-by-layer loosening. This improves the structure of the soil, moisture accumulation and aeration of the root layer, which activates the processes of nitrification and will allow plants to use additional nutrients.

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Amphiphilic Nanocarrier Systems for Curcumin Delivery in Neurodegenerative Disorders

Medicines ◽

10.3390/medicines5040126 ◽

2018 ◽

Vol 5 (4) ◽

pp. 126 ◽

Cited By ~ 23

Author(s):

Miora Rakotoarisoa ◽

Angelina Angelova

Keyword(s):

Neurodegenerative Disorders ◽

Liquid Crystalline ◽

Water Solubility ◽

Neuronal Loss ◽

Drug Solubility ◽

Neuroprotective Effects ◽

Slowing Down ◽

Combination Treatments ◽

Physico Chemical ◽

Lateral Sclerosis

Neurodegenerative diseases have become a major challenge for public health because of their incurable status. Soft nanotechnology provides potential for slowing down the progression of neurodegenerative disorders by using innovative formulations of neuroprotective antioxidants like curcumin, resveratrol, vitamin E, rosmarinic acid, 7,8-dihydroxyflavone, coenzyme Q10, and fish oil. Curcumin is a natural, liposoluble compound, which is of considerable interest for nanomedicine development in combination therapies. The neuroprotective effects of combination treatments can involve restorative mechanisms against oxidative stress, mitochondrial dysfunction, inflammation, and protein aggregation. Despite the anti-amyloid and anti-tau potential of curcumin and its neurogenesis-stimulating properties, the utilization of this antioxidant as a drug in neuroregenerative therapies has huge limitations due to its poor water solubility, physico-chemical instability, and low oral bioavailability. We highlight the developments of soft lipid- and polymer-based delivery carriers of curcumin, which help improve the drug solubility and stability. We specifically focus on amphiphilic liquid crystalline nanocarriers (cubosome, hexosome, spongosome, and liposome particles) for the encapsulation of curcumin with the purpose of halting the progressive neuronal loss in Alzheimer’s, Parkinson’s, and Huntington’s diseases and amyotrophic lateral sclerosis (ALS).

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Kinetics of solanidine hydrolytic extraction from potato (Solanum tuberosum L) haulm solid-liquid systems

Journal of the Serbian Chemical Society ◽

10.2298/jsc0301009n ◽

2003 ◽

Vol 68 (1) ◽

pp. 9-16 ◽

Cited By ~ 5

Author(s):

Nada Nikolic ◽

Mihajlo Stankovic

Keyword(s):

Solanum Tuberosum ◽

Hydrochloric Acid ◽

Solid Phase ◽

Solanum Tuberosum L ◽

Volume Ratio ◽

Single Step ◽

Ethanolic Solution ◽

Liquid Systems ◽

Solid Liquid ◽

Kinetics Of

Dried and milled haulm of potato (Solanum tuberosum L) was used as the solid phase. An ethanolic solution of hydrochloric acid mixed with chloroform in different volume ratios was the liquid phase. The aim of paper was to unite in a single step the processes of glycoalkaloids extraction from haulm, their hydrolysis to solanidine and the extraction of solanidine. This could make the procedure of obtaining solanidine faster and simpler. The best degree of solanidine hydrolytic extraction of 84.5% was achieved using 10% w/v hydrochloric acid in 96% vol. ethanol mixed with chloroform in a volume ratio of 2:3, after 120 min of hydrolytic extraction.

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Deposition Mechanisms in Layer-by-Layer or Step-by-Step Deposition Methods: From Elastic and Impermeable Films to Soft Membranes with Ion Exchange Properties

ISRN Materials Science ◽

10.5402/2012/701695 ◽

2012 ◽

Vol 2012 ◽

pp. 1-13 ◽

Cited By ~ 35

Author(s):

Marc Michel ◽

Valérie Toniazzo ◽

David Ruch ◽

Vincent Ball

Keyword(s):

Short Review ◽

Multilayer Films ◽

Film Deposition ◽

Layer By Layer ◽

Operational Parameters ◽

Polyelectrolyte Multilayer ◽

Interacting Species ◽

Growth Regime ◽

Versatile Tool ◽

Solid Liquid

The modification of solid-liquid interfaces with polyelectrolyte multilayer films appears as a versatile tool to confer new functionalities to surfaces in environmentally friendly conditions. Indeed such films are deposited by alternate dipping of the substrates in aqueous solutions containing the interacting species or spraying these solutions on the surface of the substrate. Spin coating is more and more used to produce similar films. The aim of this short review article is to provide an unifying picture about the deposition mechanisms of polyelectrolyte multilayer films. Often those films are described as growing either in a linear or in a supralinear growth regime with the number of deposited “layer pairs”. The growth regime of PEM films can be controlled by operational parameters like the temperature or the ionic strength of the used solutions. The control over the growth regime of the films as a function of the number of deposition steps allows to control their functional properties: either hard and impermeable films in the case of linear growth or soft and permeable films in the case of supralinear growth. Such different properties can be obtained with a given combination of interacting species by changing the operational parameters during the film deposition.

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Influence of galactic arm scale dynamics on the molecular composition of the cold and dense ISM III. Elemental depletion and shortcomings of the current physico-chemical models

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2016 ◽

2020 ◽

Vol 497 (2) ◽

pp. 2309-2319

Author(s):

V Wakelam ◽

W Iqbal ◽

J-P Melisse ◽

P Gratier ◽

M Ruaud ◽

...

Keyword(s):

Gas Phase ◽

Molecular Form ◽

Dense Medium ◽

Chemical Model ◽

Physical Conditions ◽

Dense Cores ◽

Chemical Models ◽

Physico Chemical ◽

Galactic Model ◽

Elemental Depletion

ABSTRACT We present a study of the elemental depletion in the interstellar medium. We combined the results of a Galactic model describing the gas physical conditions during the formation of dense cores with a full-gas-grain chemical model. During the transition between diffuse and dense medium, the reservoirs of elements, initially atomic in the gas, are gradually depleted on dust grains (with a phase of neutralization for those which are ions). This process becomes efficient when the density is larger than 100 cm−3. If the dense material goes back into diffuse conditions, these elements are brought back in the gas phase because of photo-dissociations of the molecules on the ices, followed by thermal desorption from the grains. Nothing remains on the grains for densities below 10 cm−3 or in the gas phase in a molecular form. One exception is chlorine, which is efficiently converted at low density. Our current gas–grain chemical model is not able to reproduce the depletion of atoms observed in the diffuse medium except for Cl, which gas abundance follows the observed one in medium with densities smaller than 10 cm−3. This is an indication that crucial processes (involving maybe chemisorption and/or ice irradiation profoundly modifying the nature of the ices) are missing.

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Anomalous Behaviour of the Mean Dipole Polarizability α of Neopentane C(CH3)4 in the Temperature Range between 250 K and 360 K

Zeitschrift für Naturforschung A ◽

10.1515/zna-1991-1109 ◽

1991 ◽

Vol 46 (11) ◽

pp. 983-988 ◽

Cited By ~ 3

Author(s):

Uwe Hohm ◽

Klaus Kerl

Keyword(s):

Absorption Band ◽

Temperature Dependence ◽

Anomalous Behaviour ◽

Dipole Polarizability ◽

Gaseous State ◽

Temperature Range ◽

Physico Chemical ◽

The Mean ◽

Solid Liquid

Abstract The temperature dependence of the dynamic dipole polarizability α(λ) of gaseous neopentane has been re-examined in the temperature range between T = 250 K and T - 360 K at the four HeNelaser wavelengths λ = 543.51 nm, 594.11 nm, 611.97 nm, and 632.99 nm. These interferometric measurements are compared with former determinations of the dynamic as well as the static dipole polarizability in the solid, liquid and gaseous state. In all cases, a shape of α(T) in the range between 290 K and 310 K has been observed which is similar to the shape of α (λ) in an absorption band. This observation is connected with other physico-chemical quantities of neopentane.

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Adsorptive Removal of Copper Ions from Polluted Water Using Sorbents Derived from Cordia dichotoma, Albizia thompsonii and Polyalthia cerasoides Plants

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22777 ◽

2020 ◽

Vol 32 (10) ◽

pp. 2653-2659

Author(s):

Tumma Prasanna Kumar Reddy ◽

Sayana Veerababu ◽

Malireddy Venkata Sai Mohan Reddy ◽

Kunta Ravindhranath

Keyword(s):

Activated Carbons ◽

Copper Ions ◽

Industrial Effluent ◽

Industrial Effluents ◽

Liquid Interface ◽

Polluted Water ◽

Physico Chemical ◽

Solid Liquid Interface ◽

Solid Liquid ◽

Direct Applicability

Three different activated carbons as effective adsorbents were prepared by digesting the stems of Cordia dichotoma, Albizia thompsonii and Polyalthia cerasoides plants in conc. H2SO4 for Cu2+ removal from wastewater. The sorption natures of these sorbents are optimized with respect to various physico-chemical characteristics for the maximum Cu2+ removal using simulated waters. Cordia dichotoma (CDAC), Albizia thompsonii (ATAC) and Polyalthia cerasoides (PCAC) activated carbons show good sorption capacities of values: 97.0, 76.8 and 66.7 mg/g, respectively in a wide pH ranges. Unlike that of other two activated carbons, Cordia dichotoma activated carbon is effective even in acid conditions, indicting its direct applicability to Cu-based industrial effluents which are generally acidic in nature. Interference of two fold excess of co-ions is minimal. The established extraction conditions for the removal of more than 95.0% from 10 ppm Cu2+ solution at room temperature (303 K) using CDAC as sorbent are: pH: 3-9; time of equilibration: 1 h; sorbent dosage: 0.100 g/100 mL; with ATAC: pH: 6-9; time of equilibration: 1.5 h and sorbent dosage: 0.125 g/100 mL; and with PCAC: pH: 6-9; time of equilibration: 2.0 h and sorbent dosage 0.50 g/100 mL. Spent adsorbents can be regenerated and reused until four cycles with minimal loss of adoption capacities. Thermodynamic studies revealed that the sorption is spontaneous and endothermic in nature. Further, the ΔH value for CDAC is 30.156 KJ/mol; it indicates the strong chemisorption and may be through reduction to Cu+/Cu and/or complex formation between Cu2+ and functional groups of the adsorbent. The ΔH values of other two activated carbons, ATAC and PCAC, indicated that the sorption is mainly physical with strong inclination towards chemical nature. Positive ΔS values of all the three sorbents, emphasizes the disorder or randomness at the solid-liquid interface and hence favourable conditions for more penetration of Cu2+ into the surface layers of the adsorbent and hence, more removal of Cu2+ ions. The negative ΔG values indicate that the sorption forces are good enough to cross the potential barrier at the solid-liquid interface and hence the process is spontaneous. The prepared three activated carbons were also successfully applied to industrial effluent and polluted lake samples.

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Wiener Indices and Molecular Surfaces

Zeitschrift für Naturforschung A ◽

10.1515/zna-1995-0707 ◽

1995 ◽

Vol 50 (7) ◽

pp. 669-671 ◽

Cited By ~ 7

Author(s):

Ivan Gutmana ◽

Tamás Körtvélyesi

Keyword(s):

Volume Ratio ◽

Wiener Index ◽

Molecular Surface ◽

Molecular Volume ◽

Saturated Hydrocarbons ◽

Molecular Surfaces ◽

Physico Chemical ◽

First Time

A correlation between the Wiener index (W) and the molecular surface of the respective alkane is established for the first time. This correlation is curvilinear and not particularly good. W is only weakly correlated to molecular volume of saturated hydrocarbons and does not reflect at all their surface-to-volume ratio. By this a long-existing controversy concerning the physico-chemical interpretation of W is resolved.

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X-Ray Reflectivity Measurements of Layer-by-Layer Films at the Solid/Liquid Interface

Langmuir ◽

10.1021/la802060e ◽

2008 ◽

Vol 24 (21) ◽

pp. 12093-12096 ◽

Cited By ~ 18

Author(s):

Svetlana Erokhina ◽

Tatiana Berzina ◽

Luigi Cristofolini ◽

Victor Erokhin ◽

Claudia Folli ◽

...

Keyword(s):

Liquid Interface ◽

Layer By Layer ◽

X Ray ◽

Solid Liquid Interface ◽

Solid Liquid

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On the thermocapillary motion of partially engulfed compound drops

Journal of Fluid Mechanics ◽

10.1017/s0022112009005874 ◽

2009 ◽

Vol 626 ◽

pp. 263-289 ◽

Cited By ~ 12

Author(s):

L. ROSENFELD ◽

O. M. LAVRENTEVA ◽

A. NIR

Keyword(s):

Temperature Gradient ◽

Volume Ratio ◽

Thermal Conductivity Ratio ◽

External Temperature ◽

Interfacial Tensions ◽

Thermocapillary Motion ◽

Physical Conditions ◽

Thermal Fields ◽

Induced Motion ◽

Compound Drops

In this work the thermocapillary-induced motion of partially engulfed compound drops is considered. This phenomenon occurs in many natural and technological processes in which heat is exchanged between such hybrid drops and the medium around them through the interfaces. Two types of thermal fields and the resulting motions are studied; flow induced by an external temperature gradient and spontaneous thermocapillary motion. For the first flow type, it was found that, in general, the motion is induced in the direction of the temperature gradient. However, under certain physical conditions and drops' configuration a motion against the temperature gradient may be observed. In the second case, spontaneous thermocapillary motion, the compound drop moves due to surface tension gradients which result from the geometric non-uniformity of the system. Results are presented for several parameters such as configuration of the compound drop, viscosity, thermal conductivity ratio, the dependence of the various interfacial tensions on temperature and the volume ratio of the phases within the drop.

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Solid-liquid systems for the hydrolysis of glycoalkaloids from potato (Solanum tuberosum L) tuber sprouts and solanidine isolation

Hemijska industrija ◽

10.2298/hemind0306288n ◽

2003 ◽

Vol 57 (6) ◽

pp. 288-292

Author(s):

Nada Nikolic ◽

Mihajlo Stankovic ◽

Milorad Cakic

Keyword(s):

Solanum Tuberosum ◽

Liquid Phase ◽

Hydrochloric Acid ◽

Solid Phase ◽

Solanum Tuberosum L ◽

Volume Ratio ◽

Liquid Systems ◽

Pharmacologically Active ◽

Solid Liquid ◽

Hydrolysis Of

Solanidine (C17H43O/V) is a steroidal aglycone of glycoalkaloids and an important precursor for the synthesis of hormones and some pharmacologically active compounds. Glycoalkaloids are hydrolysed by mineral acid yielding solanidine and a carbohydrate moiety. In this paper the kinetics of hydrolysis of glycoalkaloids from potato (Solanum tuberosum L) tuber sprouts by using solid-liquid systems were studied as well as solanidine isolation from the liquid phase of the system. The dried and milled tuber sprouts of potato were used as the solid phase and solutions of hydrochloric acid of different concentration in 96 % vol. ethanol, mixed with chloroform in a volume ratio of 2:3, 1:1, 3:2 and 4:1, were used as the liquid phase. The aim of the paper was to choose the optimal concentration of hydrochloric acid in ethanol, the volume ratio of hydrochloric acid in ethanol to chloroform in the liquid phase and the time for solanidine hydrolytic extraction, as well as to isolate solanidine from the liquid phase.

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