scholarly journals The Luminescent Property of Magnetic Polymers and Its Influencing Factors

2020 ◽  
Vol 213 ◽  
pp. 02011
Author(s):  
Zeren Li
Keyword(s):  
Charge Transfer ◽  
Metal Ions ◽  
Functional Groups ◽  
Influencing Factors ◽  
Luminescent Property ◽  
Luminescent Properties ◽  
Generation Mechanism ◽  
Side Chains ◽  
Factors Affecting ◽  
Practical Applications

In this paper, the generation mechanism, influencing factors and application of the luminescent properties of magnetic polymers are reviewed. In practical applications, magnetic polymers exhibit a variety of unique luminescent properties, including photoluminescence, electroluminescence and thermoluminescence. There are many factors affecting the luminescent properties of different kinds of magnetic polymers, including the types of magnetic centers, the properties of metal ions, the charge transfer between metal ions and ligands, and the influence of functional groups on the main and side chains of the polymers. This paper explains the luminescent properties of magnetic polymers from the aspects of generation mechanism and influencing factors.

scholarly journals SYNTHESIS AND SPECTRAL CHARACTERISTICS OF Cu(II), Ni(II) AND Fe(III) NANOSIZED COM­PLEXES ON THE SURFACE OF CARBON QUANTUM DOT

2021 ◽  
Vol 87 (9) ◽  
pp. 3-13
Author(s):  
Volodymyr Ogenko ◽  
Svitlana Orysyk ◽  
Ljudmila Kharkova ◽  
Oleg Yanko ◽  
Dongchu Chen
Keyword(s):  
Charge Transfer ◽  
Hydrochloric Acid ◽  
Metal Ions ◽  
Absorption Spectra ◽  
Functional Groups ◽  
Spectral Characteristics ◽  
Visible Region ◽  
Heating Time ◽  
Electron Transitions ◽  
Coordination Bonds

Processes of interaction between carbon quantum dots (CQDs) and solutions of Cu(II) Ni(II) and Fe(III) chlorides in the surface layer have been investigated by electron and IR spectroscopy. When hydrochloric acid is added to the aqueous suspension of CQDs, there is a signi­ficant batochromic shift of the average absorption band (AB) by 1285 cm-1 with a decrease in its intensity to ε = 23.39. The presence of copper in the suspension of CQDs at room temperature leads to a decrease in the intensity of this AB (ε = 21.80), which indicates the interaction of CQDs with metal ions. After heating the suspension for 1 and 3 hours, the gypsochromic shift of this ABs (by 335 cm-1) to 27790 cm-1 with a decrease in intensity depending on the heating time was recorded. Such changes in the UV–Vis Spectrum are due to the redistribution of the electron density of electron transitions n → π *due to the coordination of functional groups with metal ions and the appearance of transitions with charge transfer from ligand to metal (CQD→Cu2+). When heating the suspensions significantly increases the absorption intensity of the AB at 22070 cm-1: from ε = 4.59 to ε = 6.75, which indicates the formation of transitions with charge transfer from ligand to metal (ChTLM) due to the coordination of copper ions with CQD. In the absorption spectra of CQD suspensions with NiCl2 before heating, a hypsochromic shift of AB at 27305 cm-1 by 150 cm-1 and an increase in the intensity of its to ε = 4.95 were registered. That is, Ni(II) ions also form coordination bonds with functional groups on the periphery of the CQD. After heating hydrochloric acid suspensions of CQD with FeCl3, in contrast to the chlorides of previous metals, in the UV-region registered shoulder-shaped AB at 31545 cm-1, the intensity of which increases with heating time (from ε = 9.59 to ε = 12.10), and in the visible region, a weakly intense shoulder-shaped AB at 19345 cm-1 (ε = 3.71 and 4.58), associated with the presence of dd-electron transitions in the metal ion. Such changes in the absorption spectra are explained by the fact that iron may interact with CQD in different ways (in addition to coordination with functional donor groups, the formation of coordination bonds with the π-electron system of conjugated CQDs bonds), which leads to additional weak shoulder-like AB at 31545 cm-1. The IR-spectra data of CQDs showed the presence of a number of characteristic ABs for functionalized CQDs: ν(N–H) at 3260 сm1, (C=O) at 1830, 1840 and 1850 сm1, –С=O(NH) at 1770 сm1, ν(C=N) at 1680 and δ(N–H) at 1640 сm1 and 320-360 см-1 СП ν(Cu–Cl, Ni–Cl, Fe–Cl), which confirms the coordination of metals on the surface of CQDs.

A Strategy for Thioamide Incorporation During Fmoc Solid-Phase Peptide Synthesis with Robust Stereochemical Integrity

2019 ◽  
Author(s):  
luis camacho III ◽  
Bryan J. Lampkin ◽  
Brett VanVeller
Keyword(s):  
Amino Acid ◽  
Functional Groups ◽  
Peptide Synthesis ◽  
Solid Phase ◽  
Solid Phase Peptide Synthesis ◽  
Side Chains ◽  
Amino Acid Side Chains ◽  
Peptide Elongation

We describe a method to protect the sensitive stereochemistry of the thioamide—in analogy to the protection of the functional groups of amino acid side chains—in order to preserve the thioamide moiety during peptide elongation.<br>

scholarly journals Aphid–Plant–Phytovirus Pathosystems: Influencing Factors from Vector Behaviour to Virus Spread

Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 502
Author(s):  
Junior Corneille Fingu-Mabola ◽  
Frédéric Francis
Keyword(s):  
Influencing Factors ◽  
Virus Transmission ◽  
Physical Factors ◽  
Factors Affecting ◽  
Vector Borne Diseases ◽  
Vector Behaviour ◽  
Crop Fields ◽  
Host Seeking ◽  
The Impact ◽  
Vector Efficiency

Aphids are responsible for the spread of more than half of the known phytovirus species. Virus transmission within the plant–aphid–phytovirus pathosystem depends on vector mobility which allows the aphid to reach its host plant and on vector efficiency in terms of ability to transmit phytoviruses. However, several other factors can influence the phytoviruses transmission process and have significant epidemiological consequences. In this review, we aimed to analyse the aphid behaviours and influencing factors affecting phytovirus spread. We discussed the impact of vector host-seeking and dispersal behaviours mostly involved in aphid-born phytovirus spread but also the effect of feeding behaviours and life history traits involved in plant–aphid–phytovirus relationships on vector performances. We also noted that these behaviours are influenced by factors inherent to the interactions between pathosystem components (mode of transmission of phytoviruses, vector efficiency, plant resistance, …) and several biological, biochemical, chemical or physical factors related to the environment of these pathosystem components, most of them being manipulated as means to control vector-borne diseases in the crop fields.

scholarly journals The role of serum β-trophin and endostatin in patients with polycystic ovary syndrome: Are they correlated?

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wei Gong ◽  
Aikmu Bilixzi ◽  
Xinmei Wang ◽  
Yanli Lu ◽  
Li Wan ◽  
...  
Keyword(s):  
Polycystic Ovary Syndrome ◽  
Influencing Factors ◽  
Polycystic Ovary ◽  
Pearson Correlation ◽  
Healthy Controls ◽  
Newly Diagnosed ◽  
Ovary Syndrome ◽  
Factors Affecting ◽  
Main Factors

Abstract Background It’s necessary to investigate the serum β-trophin and endostatin (ES) level and its influencing factors in patients with newly diagnosed polycystic ovary syndrome (PCOS). Methods Newly diagnosed PCOS patients treated in our hospital were selected, and healthy women who took physical examination during the same period as healthy controls. We detected and compared the related serum indicators between two groups, Pearson correlation were conducted to identify the factors associated with β-trophin and ES, and the influencing factors of β-trophin and ES were analyzed by logistic regression. Results A total of 62 PCOS patients and 65 healthy controls were included. The BMI, WHI, LH, FSH, TT, FAI, FBG, FINS, HOMA-IR, TC, TG, LDL, ES in PCOS patients were significantly higher than that of healthy controls, while the SHBG and HDL in PCOS patients were significantly lower than that of healthy controls (all p < 0.05). β-trophin was closely associated with BMI (r = 0.427), WHR (r = 0.504), FBG (r = 0.385), TG (r = 0.405) and LDL (r = 0.302, all p < 0.05), and ES was closely associated with BMI (r = 0.358), WHR (r = 0.421), FBG (r = 0.343), TC (r = 0.319), TG (r = 0.404, all p < 0.05). TG, BMI, WHR and FBG were the main factors affecting the serum β-trophin levels (all p < 0.05). FBG, TC and BMI were the main factors affecting the serum ES levels (all p < 0.05). The TG, β-trophin, ES level in PCOS patients with insulin resistance (IR) were significantly higher than that of those without IR (all p < 0.05). Conclusion Increased β-trophin is closely associated with increased ES in patients with PCOS, which may be the useful indicators for the management of PCOS.

scholarly journals Hydroxyurea—The Good, the Bad and the Ugly

Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 1096
Author(s):  
Marcelina W. Musiałek ◽  
Dorota Rybaczek
Keyword(s):  
Cancer Progression ◽  
Specific Interaction ◽  
Interaction Mechanism ◽  
Myeloproliferative Disorders ◽  
Prolonged Treatment ◽  
Actual State ◽  
Cytotoxic Effects ◽  
Factors Affecting ◽  
Cell Cycles ◽  
Practical Applications

Hydroxyurea (HU) is mostly referred to as an inhibitor of ribonucleotide reductase (RNR) and as the agent that is commonly used to arrest cells in the S-phase of the cycle by inducing replication stress. It is a well-known and widely used drug, one which has proved to be effective in treating chronic myeloproliferative disorders and which is considered a staple agent in sickle anemia therapy and—recently—a promising factor in preventing cognitive decline in Alzheimer’s disease. The reversibility of HU-induced replication inhibition also makes it a common laboratory ingredient used to synchronize cell cycles. On the other hand, prolonged treatment or higher dosage of hydroxyurea causes cell death due to accumulation of DNA damage and oxidative stress. Hydroxyurea treatments are also still far from perfect and it has been suggested that it facilitates skin cancer progression. Also, recent studies have shown that hydroxyurea may affect a larger number of enzymes due to its less specific interaction mechanism, which may contribute to further as-yet unspecified factors affecting cell response. In this review, we examine the actual state of knowledge about hydroxyurea and the mechanisms behind its cytotoxic effects. The practical applications of the recent findings may prove to enhance the already existing use of the drug in new and promising ways.

scholarly journals A Short Review on Recent Advances of Hydrogel-Based Adsorbents for Heavy Metal Ions

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 864
Author(s):  
Suguna Perumal ◽  
Raji Atchudan ◽  
Thomas Nesakumar Jebakumar Immanuel Edison ◽  
Rajendran Suresh Babu ◽  
Petchimuthu Karpagavinayagam ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Large Scale ◽  
Water Bodies ◽  
Dimensional Structure ◽  
High Porosity ◽  
Adsorption Method ◽  
Toxic Heavy Metal ◽  
Practical Applications

The growth of industry fulfills our necessity and promotes economic development. However, pollutants from such industries pollute water bodies which pose a high risk for living organisms. Thus, researchers have been urged to develop an efficient method to remove toxic heavy metal ions from water bodies. The adsorption method shows promising results for the removal of heavy metal ions and is easy to operate on a large scale, thus can be applied to practical applications. Numerous adsorbents were developed and reported, among them hydrogels, which attract great attention because of the reusability, ease of preparation, and handling. Hydrogels are generally prepared by the cross-linking of polymers that result in a three-dimensional structure, showing high porosity and high functionality. They are hydrophilic in nature because of the functional groups, and are non-toxic. Thus, this review provides various methods of hydrogel adsorbents preparation and summarizes recent progress in the use of hydrogel adsorbents for the removal of heavy metal ions. Further, the mechanism involved in the removal of heavy metal ions is briefly discussed. The most recent studies about the adsorption method for the treatment of heavy metal ions contaminated water are presented.

scholarly journals Grey Relational Grade Based Quantitative Analysis of the Factors Influencing the Load Characteristics of A Power Grid

2018 ◽  
Vol 53 ◽  
pp. 01012 ◽  
Author(s):  
Wei Pan ◽  
Caijia Lei ◽  
Wei Jia ◽  
Hui Gao ◽  
Binghua Fang
Keyword(s):  
Quantitative Analysis ◽  
Influencing Factors ◽  
Power Grid ◽  
Grey System Theory ◽  
Grey System ◽  
Factors Affecting ◽  
Grey Relational Grade ◽  
Load Characteristics ◽  
Grey Relational ◽  
Main Factor

Regarding analysis of load characteristics of a power grid, there are multiple factors that influence the variation of load characteristics. Among these factors, the influence of different ones on the change of load characteristic is somewhat different, thus the degree of influence of various factors needs to be quantified to distinguish the main and minor factors of load characteristics. Based on this, the grey relational analysis in the grey system theory is employed as the basis of mathematical model in this paper. Firstly, the main factors affecting the load characteristics of a power grid are analysed. Then, the principle of quantitative analysis of the influencing factors by using grey relational grade is introduced. Lastly, the load of Guangzhou power grid is selected as the research object, thereby the main factor of temperature affecting the load characteristics is quantitatively analysed, such that the correlation between temperature and load is established. In this paper, by investigating the influencing factors and the degree of influence of load characteristics, the law of load characteristics changes can be effectively revealed, which is of great significance for power system planning and dispatching operation.

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