MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)最新文献

{"title":"Electrocatalytic Activity of Manganese Tetra 4-Aminophenyl Porphyrin Conjugated to Graphene Quantum Dots","authors":"Mbulelo Jokazi, L. Mpeta, T. Nyokong","doi":"10.2139/ssrn.3856018","DOIUrl":"https://doi.org/10.2139/ssrn.3856018","url":null,"abstract":"A manganese tetra 4-aminophenyl porphyrin (MnTAPP) was synthesized and conjugated to graphene quantum dots (GQDs) through  stacking and covalent linkage to give MnTAPP GQDs and MnTAPP@GQDs. The electrochemical behavior was tested by Cyclic voltammetry and chronoamperometry towards hydrazine. Both methods of conjugation  improved the activity of the electrocatalysis compared to individual components. MnTAPP@GQDs showed better catalytic activity of 4.36 × 10 2 Ms -1 and lowest LoD of 0.00237 µM followed by MnTAPP GQDs.","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76036909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Macroplastic Properties and Distribution Influenced by Field Managements with a Long-Term Plastic-Film-Mulching in Mollisols of Northeast China","authors":"Pengke Yan, Jiuqi Wang, Wan Wang, Bing Xu, Xinhua Hao, Muhammad Aurangzeib, Shaoliang Zhang","doi":"10.2139/ssrn.3929274","DOIUrl":"https://doi.org/10.2139/ssrn.3929274","url":null,"abstract":"Plastic-film-mulching (PFM) has been widely used for improving the soil moisture and temperature in the farmland, while most of them are degraded into macroplastic (MaP) in soils and cause negative effects on biota. However, it is still not clear how field management, such as tillage frequency and fertilization, influences MaP in soils. In this study, MaP was investigated at 0-20 cm and 20-30 cm soil depths in three vegetable fields (5.2 ha, 6.5 ha, and 3.4 ha) with different management methods (MM) after thirteen years’ PFM in Mollisols of Northeast China. The MM2 has the highest tillage frequency, followed by MM1 and MM3. The total fertilization after transforming into chemical fertilizers was MM1> MM2>MM3. The results showed that (1) Polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET) were the top frequently occurring MaP, melamine-formaldehyde resin (MF) and Poly (ether urethane) (PEUR) were also found. (2) PE-MaP (>87%) was the predominant MaP type mainly coming from PFM, and field cultivation increased the chances of MaP coming from the outside field. (3) Abundance, mass and accumulated areas of MaP significantly decreased from 0-20 cm to 20-30 cm soil layer, and were mainly influenced by the tillage practice. (4) MM2 has the highest abundance of MaP with size < 4 cm2, while MM3 has the highest abundance at the size of 4-16 cm2 and >16 cm2. (5) Compared with the original plastics, new function groups appeared on the surface of PE, PP, PS and PET, and both the higher fertilization and tillage frequency increased the chances of MaP oxidation. Generally, compared with low fertilization and tillage frequency, both high fertilization and high tillage frequency increased degradation of MaP, decreased negative effects of MaP sizes on crop growth, while produced more hazardous substances.","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86855130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Catalytic Behavior of La2O3-Promoted SO42-/ZrO2 in the Simultaneous Esterification and Transesterification of Palm Oil","authors":"D. Rattanaphra, Asama Temrak, S. Nuchdang, Wilasinee Kingkam, V. Puripunyavanich, Anusith Thanapimmetha, Maythee Saisriyoot, P. Srinophakun","doi":"10.2139/ssrn.3889956","DOIUrl":"https://doi.org/10.2139/ssrn.3889956","url":null,"abstract":"Catalytic behavior of La 2 O 3 promoted SO 4 2- /ZrO 2 (SZ) in the simultaneous esterification and transesterification of palm oil with 10wt% myristic acid was studied. La 2 O 3 (90% purity) derived from domestic monazite ore was introduced into SZ by impregnation method. Effects of La 2 O 3 loading and reaction parameters on the reaction behavior and the conversion were also investigated. The 20%La 2 O 3 -SZ catalyst possessed dual strong basic and acid sites which could efficiently promote both esterification and transesterification reactions. Using the 20%La 2 O 3 -SZ catalyst, the initial reaction rate of esterification and transesterification reactions was faster, and equilibrium was reached faster. The equilibrium of total fatty acid methyl ester (FAME) content of 74.51% and myristic acid methyl ester (MAME) content of 8.41% were achieved. The 20%La 2 O 3 -SZ catalyst maintained a relatively stable catalytic behavior during three reaction cycles. No significant loss in catalyst activity for esterification reaction was observed after reusing the catalyst five times without regeneration.","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81307584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction on the Theoretical Strength of Diamond, c-Bn, Cu and CeO 2","authors":"Zhao-Hua Liu, Biao Wang","doi":"10.2139/ssrn.3820203","DOIUrl":"https://doi.org/10.2139/ssrn.3820203","url":null,"abstract":"The theoretical (ideal) strength is the upper strength limit that any solid can withstand. Estimation of the theoretical strength of materials is vital for their applications. In material science field, the Griffith theory is the most widely used criterion for estimating the theoretical strength materials which sets an upper bound strength of ~ E/9. Besides, Frenkel and Orowan-Polanyi’s derivation from the force-displacement relationship using the sinusoidal correlation also gives a similar value of ~ E/10. Recently, with the improved quality of fabricated samples, people have reported the possibility of reaching or exceeding the theoretical strength. In this work, first-principles calculations based on density functional theory (DFT) is used to study the theoretical strength of four representative materials (diamond, <i>c</i>-BN, Cu, and CeO²) under uniaxial tensile loading along the low-index crystallographic directions. The results demonstrate that the theoretical strength of materials exhibit strong anisotropy. It is found that the ideal strength calculated by DFT is larger than the ideal strength predicted by Griffith theory or the approximate value of E/10, in all the four materials along some specific directions. This discrepancy is explained by the analysis of the fracture mechanism. In addition, based on the stability analysis of thermodynamical systems, the strength criterion based on the energy-strain relation was established which is verified by the DFT results.","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83357149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research Design Formation to Determine Quality Indicators of Potential API, 2. Quality Risks Arising in the Process of Scaling the Synthesis Procedure","authors":"N. Bevz, V. Mishchenko, V. Khomenko, V. Georgiyants","doi":"10.15587/2519-4852.2020.221940","DOIUrl":"https://doi.org/10.15587/2519-4852.2020.221940","url":null,"abstract":"Within the framework of the current pharmaceutical legislation, harmonized as much as possible with the EU and the USA to ensure the import / export of high-quality medicines (within the framework of the ICH and the positions of the global pharmaceutical sector), the transfer of technology for obtaining an active pharmaceutical ingredient requires taking into account many factors. Particular attention should be paid to identifying and eliminating risks that may arise when transferring a compound synthesis procedure to an industrial site. The scaling up of the synthesis procedure is accompanied by risks that can affect the quality of the final product, its safety and effectiveness. The aim. The aim of this work is to summarize information regarding the emergence of risks that may arise when scaling the method of synthesis of active biological substances and quality control methods that allow avoiding the emergence of risks in production, studying stability and further application in medical practice. Materials and methods. To carry out the research, we used the collection and analysis of data presented in modern scientific literature and documents of regulatory bodies and the results of our own experimental studies. With the help of FMEA analysis, the stages of scaling of the synthesis technique are identified, which are the most critical, and appropriate measures are proposed to reduce them. Based on the results of a survey of experts in the field of organic synthesis and pharmaceutical production, an appropriate matrix was drawn up and the priority number of risks was calculated according to three criteria: the severity of the consequences, the likelihood of influencing the stages of scaling up the synthesis method, and the degree of probability of detecting a hazard. Results. The risks arising from changes in the synthesis technology during the transfer of a laboratory procedure to a pilot and/or industrial site (simplification of the synthesis scheme, use of reagents and solvents of a different purity class, replacement of a compound isolation method, etc.) have been identified and can affect the pharmacological action, efficiency, safety and storage conditions of biologically active substances. On the basis of risk analysis, it is proposed to use quality control techniques that allow avoiding these risks in the future in the production of a biologically active compound. Conclusions. The stages of scaling up the methodology for the synthesis of a potential active compound for transfer to clinical and preclinical trials are determined, the reasons for the emergence of risks that must be taken into account in the industrial synthesis of BAS, the development of quality control methods and the preparation of an appropriate “certificate of quality” for a new biologically active compound are considered","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"135 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87912350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two-Dimensional Janus Ti 3C 2F xO 2-X MXene with Tunable Electronic and Mechanical Properties","authors":"Chenliang Li, Jing Guo, Chao-ying Wang, D. Ma, Baolai Wang","doi":"10.2139/ssrn.3742926","DOIUrl":"https://doi.org/10.2139/ssrn.3742926","url":null,"abstract":"Abstract In two-dimensional (2D) Janus materials, the asymmetric surface termination structure can significantly enhance material functionality. Here we explore the combined influence of surface termination composition and disorder on the electronic and mechanical properties of Janus T i 3 C 2 F x n O2-x (x = 0.5, 1, or 1.5, n = 1–3). Increasing compositions of surface O atoms induce weak C-p-Ti-d coupling due to a relatively strong interaction between the surface Ti and O atoms; while the presence of F in the mixed surface termination considerably enhances the C-p-Ti-d coupling strength compared with a purely F-terminated structure. Asymmetric disordered surface functionalization influences electronic structure, creating controllable mechanical properties. Mixed surface termination leads to a significant enhancement in the elastic constant. Janus Ti3C2F1O configuration is found to possess superior flexibility, with 31% critical strain, especially useful in practical large-magnitude-strain engineering. Our results provide a strategy to tune the electronic and mechanical properties of 2D materials.","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"PP 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84169790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"'High-Entropy Polymers': A New Mixing Route of Suppressed Phase Separation","authors":"Yu-Jr Huang, J. Yeh, A. Yang","doi":"10.2139/ssrn.3708726","DOIUrl":"https://doi.org/10.2139/ssrn.3708726","url":null,"abstract":"Alloys and ceramics of multi-component compositions and hence having high entropy at random solution states recently received focused attentions. The present work emulates the “high-entropy” concept by using a common solvent to prepare polymer blends from a number of polymers, which shows interesting unique phenomena and promising properties. By investigating the heterogeneous domain size (Λ) of thin solid films prepared by spin coating, we found that de-mixing, commonly observed in polymer blends, can be suppressed when the number of polymer species (n) in the blend increased. In binary blends (n=2), de-mixing occurred, manifesting a wide spread of Λ strongly influenced by the inter-segmental enthalpy and chain length. However, as n increased, the Λ distribution shrank sharply by a declining upper edge, indicating significant de-mixing suppression. The suppression is attributable to high mixing entropy and a kinetic steric effect blocking like-polymer aggregation during film formation. The de-mixing suppression was found effective in dispersing poly(9,9’-dioctylfluorene), a conjugated polymer (CP), in the optically inert n=5 blend where the CP molecules remained well separated, as shown spectroscopically, for CP fractions up to 50 wt.%, manifesting excellent efficiency performance.","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91034123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Uniaxial Compression of [001]-Oriented CaFe 2As 2 Single Crystal the Effect of Microstructure and Temperature on Superelasticity Part II: Modeling","authors":"I. Bakst, J. Sypek, S. Vijayan, Shuyang Xiao, M. Aindow, S. Lee, C. Weinberger","doi":"10.2139/ssrn.3693592","DOIUrl":"https://doi.org/10.2139/ssrn.3693592","url":null,"abstract":"Density functional theory simulations are combined with analytical models to describe the impact that defects and temperature have on the mechanical response of [001]-orientated compression of CaFe 2 As 2 . Our experiments, described in a companion paper, demonstrate that the solution in which CaFe 2 As 2 is grown (either in a Sn or FeAs solution), as well as post-growth heat treatment, can affect the mechanical response of these materials. To address these questions, we use DFT to understand the phase equilibria in the Ca-Fe-As systems and determine which defect structures and precipitates should form in the FeAs-grown CaFe 2 As 2 . Our results demonstrate that FeAs and iron should precipitate out of iron-rich CaFe 2 As 2 and that there should be a low-energy coherent interface between the precipitate and the CaFe 2 As 2 matrix that influences what actually precipitates. Additionally, the simulations show that off-stoichiometric CaFe 2 As 2 should occur through the formation of vacancies in the structure. The simulations of the mechanical response of CaFe 2 As 2 demonstrate that mechanical stiffening observed in experiments can be a result of point defects, the most likely source being As vacancies. Finally, by using free energy calculations within DFT, we show that the temperature dependent stress-strain curves can be partially explained by the inclusion of vibrational entropy differences between the orthorhombic and collapsed tetragonal phases in CaFe 2 As 2 .","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86185907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative In-Situ Study of Strength-Governed Interfacial Failure between H-Bn and Polymer-Derived Ceramic","authors":"Boyu Zhang, Xing Liu, Hua Guo, Kaiqi Yang, G. Gao, B. Sheldon, Huajian Gao, J. Lou","doi":"10.2139/ssrn.3683516","DOIUrl":"https://doi.org/10.2139/ssrn.3683516","url":null,"abstract":"Abstract To quantitatively study the toughening behavior in two-dimensional (2D) material reinforced ceramics, pull-out experiments were conducted to investigate the properties of the interface between multi-layer h-BN nanosheet and polymer-derived ceramic (PDC). By using nanoindentation-assisted micro-mechanical devices integrated with scanning electron microscopy (SEM), the interfacial sliding and failure behaviors between h-BN and PDC were systematically studied. The failure process was monitored in situ with precise quantitative measurements of the relative displacements across the interface that were obtained with digital image correlation (DIC). An analytical cohesive shear-lag model was developed, and the interfacial modulus and strength of the h-BN/PDC interface were measured to be 5.65 ± 1 GPa•µm−1 and 66.4 ± 16.8 MPa, respectively. A micromechanical analysis shows that the interfacial failure in these materials is governed by the interfacial strength at small length scales, rather than the interfacial fracture energy.","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77747268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of the Influence of Natural Antioxidant Concentrations on the Shelf Life of Sunflower Oil","authors":"N. Sytnik, E. Kunitsa, V. Mazaeva, A. Chernukha, Oleg Bezuglov, O. Bogatov, Dmytro Beliuchenko, A. Maksymov, M. Popov, I. Novik","doi":"10.15587/1729-4061.2020.209000","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.209000","url":null,"abstract":"The influence of natural antioxidants from different types of vegetable raw materials on the processes of oxidative and hydrolytic spoilage of sunflower oil during storage is studied. Plant antioxidants are more environmentally friendly and safer than synthetic ones. Green tea leaves and oak bark were used as vegetable raw materials. Water-ethanol extracts from vegetable raw materials were added to oil samples in experimental concentrations. The samples were stored in the laboratory conditions at the temperature of (20±2) °C. The study was performed for 5 months. The values of the acid and peroxide numbers were determined. The most effective blend of antioxidants showed the increase in the acid number from 0.12 to 0.20 mg KOH/g (concentration of green tea extract – 0.05 %, without the addition of oak bark extract). According to the values of the peroxide number, the most effective blends of antioxidants were the experiment points with the following green tea extract:oak bark extract ratio: (0.05:0.05) %, (0.025:0.025) %, (0.025:0.05) %, (0.05:0.025) %. To determine the induction period of oil and, accordingly, its shelf life under experimental conditions, the values of the peroxide numbers were used. It is rational to use extractives from oak bark and green tea under the following conditions: the concentration of each of the antioxidant extracts in terms of dry matter – (0.025‑0.04) %. The maximum induction period is 100 days. The efficiency of natural antioxidants in terms of the concentration of oak bark and green tea extracts is 0.05 and 0.025 %, respectively, was compared to the effectiveness of the corresponding concentration of one of the synthetic antioxidants – butylhydroxyanisole. When using butylhydroxyanisole, the induction period of oil was 65 days, and when using natural antioxidants – 74 days","PeriodicalId":18279,"journal":{"name":"MatSciRN: Computational Studies of Inorganic & Organic Materials (Topic)","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78650754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}