chemical character
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2022 ◽  
Vol 951 (1) ◽  
pp. 012046
Author(s):  
T Bachtiar ◽  
I Anas ◽  
A Sutandi ◽  
Ishak

Abstract This study was conducted to test the method of sterilization using autoclave and Co-60 gamma rays irradiation on chemical properties changes of biofertilizer carriers (Jasinga Latosols, Pasar Jumat Latosols, compost, Rawa Pening peat, Kalimantan peat). This research was conducted in July 2016 to April 2017 at Center for the Application of Isotopes and Radiation National Nuclear Energy Agency (PAIR BATAN) laboratory and Ilmu Tanah Sumber Daya Lahan Insitut Pertanian Bogor (IPB) laboratory. The design used in this study is completely randomized design, with seven treatment and five replications. The treatments provided include the control (without sterilization), sterilization using autoclave, and sterilization using gamma ray of Co-60 with doses of 10 kilo Gray (kGy), 20 kGy, 30 kGy, 40 kGy and 50 kGy. The parameters observed in this research was available Mn2+, available Fe2+, available Zn2+, and effectiveness of sterilization method. This research also showed chemical character changes in materials as shown by Fouier-Transform Infrared Spectrometer (FTIR) spectra. The results showed that the methods sterilization was gave significant effect on pH changes, the levels of available P, the levels of available nitrates, available Mn2+, available Fe2+, and available Zn2+. Autoclave has led to a higher metal increase compared to Co-60 gamma irradiation. A dose of 30 kGy is an effective dose to sterilize the carriers material.


2021 ◽  
Vol 905 (1) ◽  
pp. 012057
Author(s):  
S H Poromarto ◽  
Supyani ◽  
Supriyadi ◽  
Hadiwiyono

Abstract In the latest years, a disease epidemy of Moler caused by Fusarium oxysporum f.sp. cepae have just occurred in Brebes Central Java. The disease intensity, however, varies between the shallot production lands. Some lands show suppressive with disease intensity lower than 5%, and others are conducive to disease intensity over 50%. It is interesting that in Brebes occur suppressive and conducive soil to moler disease. The suppressiveness may be determined by environmental conditions, including chemical soil characters. This paper reports the chemical character of suppressive and conducive soil to moler disease in Brebes. The evidence shows that the suppressive soil is more fertile than that conducive one. The suppressive soil is chemically characterized by significantly higher organic mineral, C-organic, P-available, K-exchangeable, and Cation Exchange Capacity than that conducive one.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12363
Author(s):  
Paul M. Harrison

Compositionally-biased (CB) regions in biological sequences are enriched for a subset of sequence residue types. These can be shorter regions with a concentrated bias (i.e., those termed ‘low-complexity’), or longer regions that have a compositional skew. These regions comprise a prominent class of the uncharacterized ‘dark matter’ of the protein universe. Here, I report the latest version of the fLPS package for the annotation of CB regions, which includes added consideration of DNA sequences, to label the eight possible biased regions of DNA. In this version, the user is now able to restrict analysis to a specified subset of residue types, and also to filter for previously annotated domains to enable detection of discontinuous CB regions. A ‘thorough’ option has been added which enables the labelling of subtler biases, typically made from a skew for several residue types. In the output, protein CB regions are now labelled with bias classes reflecting the physico-chemical character of the biasing residues. The fLPS 2.0 package is available from: https://github.com/pmharrison/flps2 or in a Supplemental File of this paper.


Author(s):  
Zi Li ◽  
Yong Yang ◽  
Xing Nie ◽  
Tianlv Xu ◽  
Steven Kirk ◽  
...  

We seek to determine the two-way transfer of chemical character due to the coupling occurring between hydrogen-bonds and covalent-bonds known to account for the unusual strength of hydrogen-bonds in water. We have provided a vector-based quantification of the chemical character of uncoupled hydrogen-bonds and covalent-bonds and then determined the effects of two-way coupling consistent with the total local energy density H(rb) < 0 for hydrogen-bonds. We have calculated the precessions Kʹ of the eigenvectors around the bond-path for the Ehrenfest Force F(r) and compared with the corresponding QTAIM Kʹ. In doing so we explain why the Ehrenfest Force F(r) provides insights into the coupling between the hydrogen and covalent bonds whilst QTAIM cannot. Conditions for favorable transfer of electron momentum from the hydrogen atom of a sigma bond to the hydrogen-bond are found, with excellent agreement with the hydrogen-bond BCP and covalent-bond BCP separations providing the theoretical bounds for coupling.


2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Mia Juliana Siregar ◽  
Adi Nugroho

Ultisol soil is a less fertile soil characterized by low soil fertility rate, high acidity with pH<5, high Al saturation. This land has an area of 25% of the total land area of Indonesia. Riau Island is one of the provinces dominated by Ultisol land, so many land is not productive to use as agricultural land. This research was conducted to look at the characteristics of red soil in the agricultural land in Batam City after mixed with organic material in this case which is used is goat manure and chicken manure. From the results of research, the addition of goat manure and chicken manure that is incubated for 30 days can already give changes to the physical and chemical character of the soil, such as soil becoming more loose, having higher water content, increasing soil C organic, Nitorgen, P2O5, K, Mg, and Mn, able to reduce Fe levels in the soil. The addition of chicken manure can increase the available of Phosphate, gives K, Mg, and Mn higher than compared mixing blanko with goat manure. The addition of goat manure can increase the total of C organic and N in the soil is higher than chicken manure.


2021 ◽  
Vol 11 (4) ◽  
pp. 24-32
Author(s):  
Piotr Jan Niemiec

In this paper the influence of substituting the tungsten atom with an iron ion in the primary structure of the phosphotungstic heteropolyacid with the Keggin anion structure was investigated. Characterization of the electronic structure of the modified heteropolyacid was performed using: population analysis according to NBO scheme, total (TDOS) and partial (PDOS) density of states spectra, energy and chemical character of frontier orbitals (HOMO / LUMO) and the size of the HOMO-LUMO band gap. Additionally, the mechanism of interaction between the Fe2+ with H2O molecule, acting as a chemical reaction medium, was investigated. Most cases showed a significant effect of the introduced transition metal ion (Fe2+) on the above-mentioned properties in relation to the nonmodified heteropolyacid H3PW12O40.


Author(s):  
P. Vrábel ◽  
◽  
P. Šimurka ◽  
M. Maryška ◽  
P. Vl ◽  
...  

Cord appearance in the glass industry is a serious problem in high glass quality tableware production. The increased frequency of sharp cords provoked a serious analysis on cord origin and their elimination at the production line. Optical microscopy and electron microprobe analysis (EMA) were applied as direct methods for cord identification. A computational flow dynamics calculation (CFD) and process data analysis were used to verify the hypothesised source of the inhomogeneity. The hypothesis on origin of ZrO2 free cords containing high amounts of Al2O3 was postulated in relation to the refractory material composition of the forehearth. Calculations showed that the suggested mechanism at temperatures between 1200 and 1300°C was relevant. The hypothesis was supported by a change of chemical character of the cords after partial removal of the poorly resistant material. Also the average cord frequency was reduced on a production line from 53 to 17%. CFD simulations indicated that there may exist an effective mixing strategy on cord dissolution. Increasing stirrer rotation speed in a tempering part of the forehearth had a positive effect on cord disruption. The proposed stirrer set up decreased the cord frequency to less than 2%.


2020 ◽  
Vol 11 (SPL3) ◽  
pp. 319-323
Author(s):  
Ritya Mary Jibu ◽  
Keerthi Sasanka ◽  
Geetha V R

Marginal leakage is the intrusion into the space between all the restorative materials and cavity walls of fluids, bacteria, and ions. It can cause irritation of the pulp, change of color in the tooth and secondary caries, and may also result in restoration failure. The freshly placed prosthetic margins invariably leak. As time goes by there is a rise in marginal leakage associated with the manufacture of corrosion products and the expansion of other materials into the space between the tooth and the prosthesis. Dental researchers have been interested in the efficacy of the restorative materials to seal cavity margins against the entry of salivary constituents for some time. Some studies have shown that normal dentin would allow the penetration of dyes into human teeth's tubules. An analysis of later micro-leakage studies reveals that the structure of the dentin is permeable to the diffusion of fluids by natural and acquired defects. Because the enamel surface contains natural cracks and that allow the fluid to penetrate, the enamel can also have areas of hypo calcification, , chemical breakdown, abrasion, and carious lesions that increase penetration. However, enables the transportation of fluids by processes. Cutting dentin with dental pressure increases the exposed surface area and thus increases the amount of tubules available for fluid transfer into the pulp chamber. While ionic charge and chemical reactivity of diffusing fluids lead to marginal leakage, the physical and chemical character of restorative materials, and the operator's clinical skills are equally essential.


2020 ◽  
Author(s):  
Luis Angel Villaescusa ◽  
Jian Li ◽  
Zihao Gao ◽  
Junliang Sun ◽  
Miguel Camblor

<p> IDM-1 is a new silica zeolite with an ordered and well-defined framework constructed by alternating pentasil layers and interrupted layers, giving rise to an intersecting system of straight medium pores and undulating extra-large lobed pores. This unique structure was solved by rotation electron diffraction and refined against synchrotron powder X-ray diffraction data. Despite the presence of both Si(OSi)<sub>3</sub>(OH) and Si(OSi)<sub>2</sub>(OH)<sub>2</sub> sites, this new zeolite presents high thermal stability, withstanding calcination even to 1000ºC. The location of defects at specific sites of the structure results in alternating hydrophobic SiO<sub>2</sub> and hydrophilic SiO<sub>(2-x)</sub>(OH)<sub>2x</sub> intracrystalline regions. This peculiar combination of intersecting medium and extra-large pores and alternating regions of different chemical character may provide this zeolite with unique catalytic properties.</p>


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