scholarly journals Computing the Ediz eccentric connectivity index of discrete dynamic structures

Open Physics ◽  
2017 ◽  
Vol 15 (1) ◽  
pp. 354-359 ◽  
Author(s):  
Hualong Wu ◽  
Muhammad Kamran Siddiqui ◽  
Bo Zhao ◽  
Jianhou Gan ◽  
Wei Gao

AbstractFrom the earlier studies in physical and chemical sciences, it is found that the physico-chemical characteristics of chemical compounds are internally connected with their molecular structures. As a theoretical basis, it provides a new way of thinking by analyzing the molecular structure of the compounds to understand their physical and chemical properties. In our article, we study the physico-chemical properties of certain molecular structures via computing the Ediz eccentric connectivity index from mathematical standpoint. The results we yielded mainly apply to the techniques of distance and degree computation of mathematical derivation, and the conclusions have guiding significance in physical engineering.

2018 ◽  
Vol 74 (1-2) ◽  
pp. 25-33 ◽  
Author(s):  
Zahid Iqbal ◽  
Muhammad Ishaq ◽  
Adnan Aslam ◽  
Wei Gao

AbstractPrevious studies show that certain physical and chemical properties of chemical compounds are closely related with their molecular structure. As a theoretical basis, it provides a new way of thinking by analyzing the molecular structure of the compounds to understand their physical and chemical properties. The molecular topological indices are numerical invariants of a molecular graph and are useful to predict their bioactivity. Among these topological indices, the eccentric-connectivity index has a prominent place, because of its high degree of predictability of pharmaceutical properties. In this article, we compute the closed formulae of eccentric-connectivity–based indices and its corresponding polynomial for water-soluble perylenediimides-cored polyglycerol dendrimers. Furthermore, the edge version of eccentric-connectivity index for a new class of dendrimers is determined. The conclusions we obtained in this article illustrate the promising application prospects in the field of bioinformatics and nanomaterial engineering.


Open Physics ◽  
2017 ◽  
Vol 15 (1) ◽  
pp. 261-269
Author(s):  
Jianzhang Wu ◽  
Mohammad Reza Farahani ◽  
Xiao Yu ◽  
Wei Gao

AbstractIt’s revealed from the earlier researches that many physical-chemical properties depend heavily on the structure of corresponding moleculars. This fact provides us an approach to measure the physical-chemical characteristics of substances and materials. In our article, we report the eccentricity related indices of certain important molecular structures from mathematical standpoint. The eccentricity version indices of nanostar dendrimers are determined and the reverse eccentric connectivity index for V-phenylenic nanotorus is discussed. The conclusions we obtained mainly use the trick of distance computation and mathematical derivation, and the results can be applied in physics engineering.


2021 ◽  
Vol 22 (15) ◽  
pp. 8191
Author(s):  
Fumihiro Kawagoe ◽  
Sayuri Mototani ◽  
Atsushi Kittaka

The discovery of a large variety of functions of vitamin D3 and its metabolites has led to the design and synthesis of a vast amount of vitamin D3 analogues in order to increase the potency and reduce toxicity. The introduction of highly electronegative fluorine atom(s) into vitamin D3 skeletons alters their physical and chemical properties. To date, many fluorinated vitamin D3 analogues have been designed and synthesized. This review summarizes the molecular structures of fluoro-containing vitamin D3 analogues and their synthetic methodologies.


2021 ◽  
pp. 10-24
Author(s):  
C. R. Abah ◽  
C. N. Ishiwu ◽  
J. E. Obiegbuna ◽  
E. F. Okpalanma ◽  
C. S. Anarado

Quality cassava(Manihotesculentus, Crantz) flour is often influenced by process variables such as slice weight and soaking time which may affect its nutritional quality. In this study, the effect of process variables (slice weight and soaking time) on quality of cassava flour was carried out. Cassava root was peeled, washed and cut into varied sizes (25.86 - 54.14 g) and soaked at varied time (7.03 - 40.97 h). The proximate composition, physical and chemical properties of the flour were carried out using standard methods. The result in our findings showed that slice weight and soaking time had significant increase (p<0.05) on the proximate and physico-chemical properties of the flour.The amylose and amylopectin content of the flour increased with increasing soaking time while the hydrogen cyanide content decreased with increase in soaking time. Overall, the quality cassava flour displayed desirable properties for its incorporation into baked goods.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Christian Haynl ◽  
Jitraporn Vongsvivut ◽  
Kai R. H. Mayer ◽  
Hendrik Bargel ◽  
Vanessa J. Neubauer ◽  
...  

Abstract Our understanding of the extraordinary mechanical and physico-chemical properties of spider silk is largely confined to the fibers produced by orb-weaving spiders, despite the diversity of foraging webs that occur across numerous spider families. Crab spiders (Thomisidae) are described as ambush predators that do not build webs, but nevertheless use silk for draglines, egg cases and assembling leaf-nests. A little-known exception is the Australian thomisid Saccodomus formivorus, which constructs a basket-like silk web of extraordinary dimensional stability and structural integrity that facilitates the capture of its ant prey. We examined the physical and chemical properties of this unusual web and revealed that the web threads comprise microfibers that are embedded within a biopolymeric matrix containing additionally longitudinally-oriented submicron fibers. We showed that the micro- and submicron fibers differ in their chemical composition and that the web threads show a remarkable lateral resilience compared with that of the major ampullate silk of a well-investigated orb weaver. Our novel analyses of these unusual web and silk characteristics highlight how investigations of non-model species can broaden our understanding of silks and the evolution of foraging webs.


2020 ◽  
Vol 9 (1) ◽  
pp. 46-53
Author(s):  
V. A. Shelekhova ◽  
K. R. Savelyeva ◽  
S. V. Polyakov ◽  
V. N. Shestakov

Introduction. Pantoprazole sodium sesquihydrate is a proton pump inhibitor. This substance is used in the treatment of peptic ulcer of the duodenum or stomach in the acute phase, including those associated with the use of non-steroidal anti-inflammatory drugs.Text. Pantoprazole is sodium 5-(difluoromethoxy)-2-[(RS)-[(3,4-dimethoxypyridin-2-yl)methyl]sulfinyl]benzimidazol-1-ide sesquihydrate in its structure. The substance is readily soluble in water and ethyl alcohol. The identification of pantoprazole is confirmed by infrared absorption spectrophotometry, as well as by a positive reaction to sodium ion. For the assay of this substance chemical and physico-chemical methods are used. The first group of methods includes titration in a non-aqueous medium with perchloric acid and permanganatometry. Physico-chemical methods used for pantoprazole assay are spectrophotometry and HPLC. The most commonly used method is direct spectrophotometry associated with the measurement of optical density at a wavelength of the maximum absorption of pantoprazole in various solvents. In addition, spectrophotometric methods of assay are known, based on the study of the absorption of colored pantoprazode reaction products. The derivative spectrophotometry is used for the analysis of its preparations. The control of the content of impurities and pantoprazole in the substance and its dosage forms is carried out, as a rule, using HPLC.Conclusion. An analysis of the literature has shown that this substance is unstable. Therefore, this feature of pantoprazole must be considered when choosing excipients when developing a dosage form. The preferred method for analyzing pantoprazole preparations is HPLC, since it is possible to determine the substance in the presence of other compounds, which will allow one to control the quantitative content and stability of pantoprazole in the preparation.


Author(s):  
Nemah Sahib Mohammed Husien ◽  
Rajaa Abd Alameer Gafel ◽  
Noor Dia Jaffer

This  literature  involved  explanation  about  separation organic  components  in  mixture such  as(chromatography ,extraction ,filtration, centrifuge…) , principles of separation  , methods of separation ,types of separation , purification  of separated  compounds , conditions of separation , physical and chemical properties of  mixture.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yang Li ◽  
Li Qiao ◽  
Cong Chen ◽  
Zhenguo Wang ◽  
Xianjun Fu

Abstract Background The sentence of “Danshen (Salvia Miltiorrhizae Radix et Rhizoma) and Siwu decoction are similar in function” was first recorded in an ancient Chinese medical book “Fu Ren Ming Li Lun”. This theory has far-reaching influence on the clinical practice of Chinese medicine and is highly respected by Chinese medical doctors. However, the theory has limitations and controversial part for there is no in-depth and system comparative study. Methods We collected the molecular structures of 129 compounds of Danshen and 81 compounds of Siwu decoction from the literatures. MACCS fingerprints and Tanimoto similarity were calculated based on the molecular structures for comparing the structural feature. Molecular descriptors which represent physical and chemical properties were calculated by Discovery Studio. Principal component analysis (PCA) of was performed based on the descriptors. The ADMET properties were predicted by FAF-Drugs4. The effect targets for the compounds with good ADMET properties were confirmed from experimental data and predicted using the algorithm comprising Bernoulli Naive Bayes profiling. Results Based on the molecular structures, the presented study compared the structural feature, physical and chemical properties, ADMET properties, and effect targets of compounds of Danshen and Siwu decoction. It is found that Danshen and Siwu decoction do not have the same main active components. Moreover, the 2D structure of compounds from Danshen and Siwu decoction is not similar. Some of the compounds of Danshen and Siwu decoction are similar in 3D structure. The compounds with good ADMET properties of Danshen and Siwu decoction have same predicted targets, but some have different targets. Conclusions It can be inferred from the result that Danshen and Siwu decoction have some similarities, but also present differences from each other in the structure of the compounds and predicted targets. This may be the material basis of the similar and different traditional efficacy of Danshen and Siwu decoction. The setence of “ Danshen and Siwu decoction are similar in function. “ which is used in clinical has its material basis and target connotation to some extent. However, the traditional effects of Danshen and Siwu decoction are not exactly the same.


Author(s):  
S. Kantharaju ◽  
M. Mylarappa

The present work is focus on physical and chemical properties of purified Carboxylesterase using the Seeds of Tamarindus Indica.The esterases are extracted from the germinating tamarind seeds using 50 mM phosphate buffer, pH 7 and purified. The Km with α-naphthyl acetate, β-naphthyl acetate and α-naphthyl butyrate as the substrates is 28.6 μM, 22.2 μM and 26.7 μM respectively. The Vmax for the same substrates is 7.1 x 10-3 µmole/min, 7.41 x 10-3 µmole/min and 8.00 x 10-3 µmole/min respectively. The enzymes optimally active at pH 7.0 and are stable between pH 5.0 to 8.0. The optimum temperature of esterase activity is 40˚C. The molecular weight of 27.5 kD as determined by SDS-PAGE, both in the presence and absence of β-mercaptothanol and is in close agreement with the molecular weight determined by gel-filtration on Sephadex G-100 (26.9 kD).


Sign in / Sign up

Export Citation Format

Share Document