Artículos de revistas: "Crystal Engineering Approach"

1

Lutfiyah, Dhea Sultana, Lili Fitriani, Muhammad Taher y Erizal Zaini. "Crystal Engineering Approach in Physicochemical Properties Modifications of Phytochemical". Science and Technology Indonesia 7, n.º 3 (28 de julio de 2022): 353–71. http://dx.doi.org/10.26554/sti.2022.7.3.353-371.

Texto completo

Resumen

Phytochemicals have been used to reduce the risk of diseases and maintain good health and well-being. However, most phytochemicals have a limitation in their physicochemical properties, which can be modified by reforming the shape of the crystals. Therefore, crystal engineering is a promising approach to optimize physicochemical characteristics of the active pharmaceutical ingredients (APIs) in a phytochemical without altering its pharmacological efficacy. Hence, this paper reviews current strategies for the use of crystal engineering to optimize physicochemical properties of phytochemicals, which is followed by the design of the synthesis and characterization of particular phytochemicals, including piperine (PIP), quercetin (QUE), curcumin (CUR), genistein (GEN), and myricetin (MYR). The literature indicates that crystal engineering of multicomponent crystals (MCCs) enhances phytochemical physicochemical properties, including solubility, dissolution rate, stability, and permeability. The MCCs provide a lower lattice energy and noncovalent bonding, which translate into lower melting points and weak intermolecular interactions that generate greater solubility, higher dissolution rate, and better stability of the APIs. Nevertheless, the absence of reported studies of phytochemical crystal engineering leads to a lack of variation in the selection of coformers, methods of preparation, and improvement of physicochemical properties. Therefore, more extensive evaluation of the design and physicochemical characteristics of phytochemicals using MCCs is necessary and manifests the opportunity to enhance the application of phytochemicals in the pharmaceutical industry.

Los estilos APA, Harvard, Vancouver, ISO, etc.

2

Paul, Mithun y Gautam R. Desiraju. "Designing multi-component molecular crystals: a crystal engineering approach". Acta Crystallographica Section A Foundations and Advances 73, a2 (1 de diciembre de 2017): C675. http://dx.doi.org/10.1107/s2053273317088982.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

3

Krishna, Gamidi, Ramesh Devarapalli, Garima Lal y C. Reddy. "Design of Mechanically Flexible Organic Crystals: A Crystal Engineering Approach". Acta Crystallographica Section A Foundations and Advances 70, a1 (5 de agosto de 2014): C648. http://dx.doi.org/10.1107/s2053273314093516.

Texto completo

Resumen

Utilization of organic single crystal materials is increasing day by day owing to their promising applications in organic light emitting diodes [1], organic solar cells, mechanochromic luminescence [2] and tablatability [3] of APIs etc. These desirable functions, especially mechanical properties, can be achieved by imparting soft nature in organic materials, however unfortunately there is no simple strategy to attain this. Till date all the findings are serendipitous discoveries, so a rational design strategy is necessary to accomplish such soft mechanical behavior in molecular crystals. Here we propose a design strategy to attain plastically deformable organic materials by introducing slip planes in the crystal structures. The high plasticity can be achieved by introducing hydrophobic groups, such as t-Bu, -OMe, -Me and multiple –Cl (or) –Br groups on -Ar building blocks, for example on naphthalene diimide (NDI), which leads to the formation of slip planes in the crystal structures (as shown in attached figure), hence facilitate the plastic (irreversible) bending [2].

Los estilos APA, Harvard, Vancouver, ISO, etc.

4

Mann, Stephen. "Biomineralization: a novel approach to crystal engineering". Endeavour 15, n.º 3 (enero de 1991): 120–25. http://dx.doi.org/10.1016/0160-9327(91)90155-5.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

5

Matsumoto, Yuji, Shingo Maruyama y Kenichi Kaminaga. "Compositionally graded crystals as a revived approach for new crystal engineering for the exploration of novel functionalities". CrystEngComm 24, n.º 13 (2022): 2359–69. http://dx.doi.org/10.1039/d2ce00041e.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

6

Anand, Rachna, Arun Kumar y Arun Nanda. "Pharmaceutical Co-Crystals - Design, Development and Applications". Drug Delivery Letters 10, n.º 3 (10 de septiembre de 2020): 169–84. http://dx.doi.org/10.2174/2210303109666191211145144.

Texto completo

Resumen

Background: Solubility and dissolution profile are the major factors which directly affect the biological activity of a drug and these factors are governed by the physicochemical properties of the drug. Crystal engineering is a newer and promising approach to improve physicochemical characteristics of a drug without any change in its pharmacological action through a selection of a wide range of easily available crystal formers. Objective: The goal of this review is to summarize the importance of crystal engineering in improving the physicochemical properties of a drug, methods of design, development, and applications of cocrystals along with future trends in research of pharmaceutical co-crystals. Co-crystallization can also be carried out for the molecules which lack ionizable functional groups, unlike salts which require ionizable groups. Conclusion: Co-crystals is an interesting and promising research area amongst pharmaceutical scientists to fine-tune the physicochemical properties of drug materials. Co-crystallization can be a tool to increase the lifecycle of an older drug molecule. Crystal engineering carries the potential of being an advantageous technique than any other approach used in the pharmaceutical industry. Crystal engineering offers a plethora of biopharmaceutical and physicochemical enhancements to a drug molecule without the need of any pharmacological change in the drug.

Los estilos APA, Harvard, Vancouver, ISO, etc.

7

Lombardo, Giuseppe M., Antonio Rescifina, Ugo Chiacchio, Alessia Bacchi y Francesco Punzo. "A top–down approach to crystal engineering of a racemic Δ2-isoxazoline". Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 70, n.º 1 (16 de enero de 2014): 172–80. http://dx.doi.org/10.1107/s2052520613030862.

Texto completo

Resumen

The crystal structure of racemic dimethyl (4RS,5RS)-3-(4-nitrophenyl)-4,5-dihydroisoxazole-4,5-dicarboxylate, C13H12N2O7, has been determined by single-crystal X-ray diffraction. By analysing the degree of growth of the morphologically important crystal faces, a ranking of the most relevant non-covalent interactions determining the crystal structure can be inferred. The morphological information is considered with an approach opposite to the conventional one: instead of searching inside the structure for the potential key interactions and using them to calculate the crystal habit, the observed crystal morphology is used to define the preferential lines of growth of the crystal, and then this information is interpreted by means of density functional theory (DFT) calculations. Comparison with the X-ray structure confirms the validity of the strategy, thus suggesting this top–down approach to be a useful tool for crystal engineering.

Los estilos APA, Harvard, Vancouver, ISO, etc.

8

Chopra, Deepak y Dhananjay Dey. "Computational approaches towards crystal engineering in molecular crystals". Acta Crystallographica Section A Foundations and Advances 70, a1 (5 de agosto de 2014): C642. http://dx.doi.org/10.1107/s2053273314093577.

Texto completo

Resumen

The investigation of a large number of crystal structures has resulted in the development of the area of crystal engineering, which involves the study of intermolecular interactions in crystalline solids [1]. It is now of importance to understand the nature and energetics associated with different interactions [2] which influence the crystal packing. In this regard, different computational approaches (utilizing PIXEL and TURBOMOLE) have been developed which aid in the understanding of intra- and intermolecular interactions (for example, hydrogen and halogen bonding) in molecular crystals. This approach has been successfully applied in different classes of molecules [3]. These approaches can be combined with topological analysis of the electron density using the quantum theory of atoms in molecules (QTAIM) (in absence of high quality crystals for experimental electron density studies). In order to validate the above-mentioned methodology, we have performed a comprehensive analysis of a series of synthesized fluoro-derivatives of N'-phenylbenzimidamide to gain quantitative insights into different interactions which accompany crystal formation. The packing of the molecules has contributions from strong N-H...N, weak N-H...π [Fig 1], C-H...N, C-H...F, and C-H...π intermolecular interactions along with π-π stacking. In addition to that, ubiquitous H...H contacts are also present in the solid state. This methodology can be extended to include cocrystals, polymorphs (including solvates) and protein-ligand interactions at the active site.

Los estilos APA, Harvard, Vancouver, ISO, etc.

9

Chen, Jia-Mei, Zi-Zhou Wang, Chuan-Bin Wu, Song Li y Tong-Bu Lu. "Crystal engineering approach to improve the solubility of mebendazole". CrystEngComm 14, n.º 19 (2012): 6221. http://dx.doi.org/10.1039/c2ce25724f.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

10

Talatahari, Babak, Mahdi Azizi, Siamak Talatahari, Mohamad Tolouei y Pooya Sareh. "Crystal structure optimization approach to problem solving in mechanical engineering design". Multidiscipline Modeling in Materials and Structures 18, n.º 1 (1 de marzo de 2022): 1–23. http://dx.doi.org/10.1108/mmms-10-2021-0174.

Texto completo

Resumen

PurposeIn this paper, the authors aim to examine and comparatively evaluate a recently-developed metaheuristic called crystal structure algorithm (CryStAl) – which is inspired by the symmetries in the internal structure of crystalline solids – in solving engineering mechanics and design problems.Design/methodology/approachA total number of 20 benchmark mathematical functions are employed as test functions to evaluate the overall performance of the proposed method in handling various functions. Moreover, different classical and modern metaheuristic algorithms are selected from the optimization literature for a comparative evaluation of the performance of the proposed approach. Furthermore, five well-known mechanical design examples are utilized to examine the capability of the proposed method in dealing with challenging optimization problems.FindingsThe results of this study indicated that, in most cases, CryStAl produced more accurate outputs when compared to the other metaheuristics examined as competitors.Research limitations/implicationsThis paper can provide motivation and justification for the application of CryStAl to solve more complex problems in engineering design and mechanics, as well as in other branches of engineering.Originality/valueCryStAl is one of the newest metaheuristic algorithms, the mathematical details of which were recently introduced and published. This is the first time that this algorithm is applied to solving engineering mechanics and design problems.

Los estilos APA, Harvard, Vancouver, ISO, etc.

11

Mukherjee, Gargi y Kumar Biradha. "Topological Equivalences between Coordination Polymer and Co-crystal: A Tecton Approach in Crystal Engineering". Crystal Growth & Design 14, n.º 2 (15 de enero de 2014): 419–22. http://dx.doi.org/10.1021/cg401858s.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

12

Vaghela, Pooja D. y H. M. Tank. "Improvement in Pharmacokinetic Parameters of Ibuprofen by Crystal Engineering Approach". Indo Global Journal of Pharmaceutical Sciences 10, n.º 01 (2020): 19–24. http://dx.doi.org/10.35652/igjps.2020.10103.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

13

Sahoo, P., D. K. Kumar, S. R. Raghavan y P. Dastidar. "The crystal engineering approach to design the pheromone releasing LMWG". Acta Crystallographica Section A Foundations of Crystallography 67, a1 (22 de agosto de 2011): C231. http://dx.doi.org/10.1107/s0108767311094220.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

14

Nath, Krishna G., Oleksandr Ivasenko, Jennifer M. MacLeod, Jill A. Miwa, James D. Wuest, Antonio Nanci, Dmitrii F. Perepichka y Federico Rosei. "Crystal Engineering in Two Dimensions: An Approach to Molecular Nanopatterning". Journal of Physical Chemistry C 111, n.º 45 (noviembre de 2007): 16996–7007. http://dx.doi.org/10.1021/jp0762774.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

15

Collier, E. A., R. J. Davey, R. J. Roberts y S. N. Black. "A crystallisation/crystal engineering approach to aid salt selection - anions". Acta Crystallographica Section A Foundations of Crystallography 58, s1 (6 de agosto de 2002): c321. http://dx.doi.org/10.1107/s0108767302097805.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

16

Lai, Hanjian y Feng He. "Crystal Engineering in Organic Photovoltaic Acceptors: A 3D Network Approach". Advanced Energy Materials 10, n.º 47 (29 de octubre de 2020): 2002678. http://dx.doi.org/10.1002/aenm.202002678.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

17

Paz, Filipe A. Almeida y Jacek Klinowski. "Designing novel organic–inorganic frameworks". Pure and Applied Chemistry 79, n.º 6 (1 de enero de 2007): 1097–110. http://dx.doi.org/10.1351/pac200779061097.

Texto completo

Resumen

Crystal engineering of coordination frameworks is a topical and rapidly advancing field, and a variety of entirely new solid materials have been synthesized. We describe the main challenges involved in the hydrothermal approach to these materials using, as an example, cadmium- and zinc-based coordination frameworks. We discuss the unusual crystal architectures of the products, and show that the kind and quality of the resulting crystals are directly controlled by the composition of the ternary reactive mixture and the temperature regime used in the hydrothermal synthesis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

18

Staar, Marcel, Sophie Staar y Anett Schallmey. "Crystal Contact Engineering for Enhanced Cross-Linking Efficiency of HheG Crystals". Catalysts 12, n.º 12 (1 de diciembre de 2022): 1553. http://dx.doi.org/10.3390/catal12121553.

Texto completo

Resumen

The generation of cross-linked enzyme crystals is a very attractive method for immobilization of enzymes displaying high crystalizability. However, the commonly used cross-linker glutaraldehyde is not always compatible with enzyme activity. Therefore, we previously reported the engineering of halohydrin dehalogenase HheG from Ilumatobacter coccineus to enable thiol-specific cross-linking during CLEC generation by insertion of cysteine residues in the crystal contact. To broaden the applicability of this approach, herein crystal contact engineering of HheG has been performed to incorporate additional lysine residues as defined cross-linking sites for CLEC generation. Using the primary amine-specific cross-linker dithiobis(succinimidyl propionate) (DSP), CLECs of HheG variant V46K were obtained that displayed a high gain in thermal stability compared to wild-type HheG, while using only a low cross-linker concentration. Moreover, respective V46K CLECs exhibited a 10 K higher reaction temperature optimum as well as significantly improved activity and stability at acidic pH and in the presence of organic co-solvents. Overall, our study demonstrates that lysine-specific cross-linkers can also be used as an alternative to glutaraldehyde for stable CLEC generation of halohydrin dehalogenases, and that cross-linking efficiency is significantly improved upon crystal contact engineering.

Los estilos APA, Harvard, Vancouver, ISO, etc.

19

Geng, Yina, Greg van Anders, Paul M. Dodd, Julia Dshemuchadse y Sharon C. Glotzer. "Engineering entropy for the inverse design of colloidal crystals from hard shapes". Science Advances 5, n.º 7 (julio de 2019): eaaw0514. http://dx.doi.org/10.1126/sciadv.aaw0514.

Texto completo

Resumen

Throughout the physical sciences, entropy stands out as a pivotal but enigmatic concept that, in materials design, typically takes a backseat to energy. Here, we demonstrate how to precisely engineer entropy to achieve desired colloidal crystals via particle shapes that, importantly, can be made in the laboratory. We demonstrate the inverse design of symmetric hard particles that assemble six different target colloidal crystals due solely to entropy maximization. Our approach efficiently samples 108 particle shapes from 92- and 188-dimensional design spaces to discover thermodynamically optimal shapes. We design particle shapes that self-assemble into known crystals with optimized symmetry and thermodynamic stability, as well as new crystal structures with no known atomic or other equivalent.

Los estilos APA, Harvard, Vancouver, ISO, etc.

20

Tupe, Suraj Ankush, Shital Prabhakar Khandagale y Amrapali B. Jadhav. "Pharmaceutical Cocrystals: An Emerging Approach to Modulate Physicochemical Properties of Active Pharmaceutical Ingredients". Journal of Drug Delivery and Therapeutics 13, n.º 4 (15 de abril de 2023): 101–12. http://dx.doi.org/10.22270/jddt.v13i4.6016.

Texto completo

Resumen

Most of the Active Pharmaceutical Ingredients (APIs) are typically formulated and administered to patients in oral solid dosage forms due to ease of administration, patient compliance and cost effectiveness. Poor water solubility, low permeability and low bioavailability of APIs are major hurdles in development of oral solid dosage forms. In recent years, cocrystal development has evolved as a feasible approach for enhancing the solubility and bioavailability of poorly soluble drugs. Crystal engineering strategies have been asserted to enhance the likelihood of discovering new solid forms of an API. A pharmaceutical cocrystal is made up of two basic components, an API and a harmless material known as a coformer in stoichiometric ratio. Cocrystallization of an API with a pharmaceutically acceptable coformer can improve the physical characteristics of the API, such as solubility, hygroscopicity, and compaction behavior, without affecting the API's pharmacological efficacy. This review article offers a comprehensive overview of pharmaceutical cocrystals, their physiochemical characteristics, and methods of preparation, with an emphasis on cocrystal screening and cocrystal characterization. The review also included recent FDA and EMA guidance on pharmaceutical cocrystals as well as an outline of multidrug cocrystals. Keywords: Pharmaceutical co-crystals, crystal engineering, coformers, supramolecular synthons, Solubility

Los estilos APA, Harvard, Vancouver, ISO, etc.

21

Lian, Weiguang, Yulong Lin, Min Wang, Caiqin Yang y Jing Wang. "Crystal engineering approach to produce complex of azelnidipine with maleic acid". CrystEngComm 15, n.º 19 (2013): 3885. http://dx.doi.org/10.1039/c3ce26967a.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

22

Nam, Ki Hyun. "Processing of Multicrystal Diffraction Patterns in Macromolecular Crystallography Using Serial Crystallography Programs". Crystals 12, n.º 1 (13 de enero de 2022): 103. http://dx.doi.org/10.3390/cryst12010103.

Texto completo

Resumen

Cryocrystallography is a widely used method for determining the crystal structure of macromolecules. This technique uses a cryoenvironment, which significantly reduces the radiation damage to the crystals and has the advantage of requiring only one crystal for structural determination. In standard cryocrystallography, a single crystal is used for collecting diffraction data, which include single-crystal diffraction patterns. However, the X-ray data recorded often may contain diffraction patterns from several crystals. The indexing of multicrystal diffraction patterns in cryocrystallography requires more precise data processing techniques and is therefore time consuming. Here, an approach for processing multicrystal diffraction data using a serial crystallography program is introduced that allows for the integration of multicrystal diffraction patterns from a single image. Multicrystal diffraction data were collected from lysozyme crystals and processed using the serial crystallography program CrystFEL. From 360 images containing multicrystal diffraction patterns, 1138 and 691 crystal lattices could be obtained using the XGANDALF and MOSFLM indexing algorithms, respectively. Using this indexed multi-lattice information, the crystal structure of the lysozyme could be determined successfully at a resolution of 1.9 Å. Therefore, the proposed approach, which is based on serial crystallography, is suitable for processing multicrystal diffraction data in cryocrystallography.

Los estilos APA, Harvard, Vancouver, ISO, etc.

23

Dhondale, Madhukiran R., Pradip Thakor, Amritha G. Nambiar, Maan Singh, Ashish K. Agrawal, Nalini R. Shastri y Dinesh Kumar. "Co-Crystallization Approach to Enhance the Stability of Moisture-Sensitive Drugs". Pharmaceutics 15, n.º 1 (5 de enero de 2023): 189. http://dx.doi.org/10.3390/pharmaceutics15010189.

Texto completo

Resumen

Stability is an essential quality attribute of any pharmaceutical formulation. Poor stability can change the color and physical appearance of a drug, directly impacting the patient’s perception. Unstable drug products may also face loss of active pharmaceutical ingredients (APIs) and degradation, making the medicine ineffective and toxic. Moisture content is known to be the leading cause of the degradation of nearly 50% of medicinal products, leading to impurities in solid dose formulations. The polarity of the atoms in an API and the surface chemistry of API particles majorly influence the affinity towards water molecules. Moisture induces chemical reactions, including free water that has also been identified as an important factor in determining drug product stability. Among the various approaches, crystal engineering and specifically co-crystals, have a proven ability to increase the stability of moisture-sensitive APIs. Other approaches, such as changing the salt form, can lead to solubility issues, thus making the co-crystal approach more suited to enhancing hygroscopic stability. There are many reported studies where co-crystals have exhibited reduced hygroscopicity compared to pure API, thereby improving the product’s stability. In this review, the authors focus on recent updates and trends in these studies related to improving the hygroscopic stability of compounds, discuss the reasons behind the enhanced stability, and briefly discuss the screening of co-formers for moisture-sensitive drugs.

Los estilos APA, Harvard, Vancouver, ISO, etc.

24

Gonz´lez Mantero, D., A. Neels, F. Stoeckli y H. Stoeckli-Evans. "2-D and 3-D metal-organic frameworks: a crystal engineering approach". Acta Crystallographica Section A Foundations of Crystallography 61, a1 (23 de agosto de 2005): c363—c364. http://dx.doi.org/10.1107/s0108767305084527.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

25

Yan, Yan, Jia-Mei Chen y Tong-Bu Lu. "Simultaneously enhancing the solubility and permeability of acyclovir by crystal engineering approach". CrystEngComm 15, n.º 33 (2013): 6457. http://dx.doi.org/10.1039/c3ce41017j.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

26

Adarsh, N. N., Pathik Sahoo y Parthasarathi Dastidar. "Is a Crystal Engineering Approach Useful in Designing Metallogels? A Case Study". Crystal Growth & Design 10, n.º 11 (3 de noviembre de 2010): 4976–86. http://dx.doi.org/10.1021/cg101078f.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

27

An, Guanghui, Pengfei Yan, Jingwen Sun, Yuxin Li, Xu Yao y Guangming Li. "The racemate-to-homochiral approach to crystal engineering via chiral symmetry breaking". CrystEngComm 17, n.º 24 (2015): 4421–33. http://dx.doi.org/10.1039/c5ce00402k.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

28

GAN, YONG X. y XI CHEN. "MACRO- AND MICROSCOPIC APPROACHES TO PLANE STRAIN DEFORMATION STATES OF FACE-CENTERED CUBIC METALS UNDER WEDGE INDENTATION". International Journal of Applied Mechanics 01, n.º 01 (marzo de 2009): 41–60. http://dx.doi.org/10.1142/s1758825109000022.

Texto completo

Resumen

Face-centered cubic (FCC) metals show active slip under indentation loading. In this work, both macro- and microscopic models are proposed to analyze the deformation behavior of face-centered-cubic (FCC) single crystals under wedge indentation. In the part of macroscopic approach, stress distribution and anisotropic yielding were investigated. Load-displacement relation was obtained to reveal the mechanical responses of the crystals. In the microscopic approach section, an indention induced lattice rotation zone was identified and the deformation behavior was analyzed using the single crystal plasticity theory. The crystal lattice rotation experimental results and slip line trace observations validate the analytical predictions.

Los estilos APA, Harvard, Vancouver, ISO, etc.

29

Roy Choudhury, Angshuman, Gurpreet Kaur, Maheswararao Karanam y Sandhya Patel. ""Organic Fluorine" and its Importance in Crystal Engineering". Acta Crystallographica Section A Foundations and Advances 70, a1 (5 de agosto de 2014): C669. http://dx.doi.org/10.1107/s2053273314093309.

Texto completo

Resumen

The phrase "Organic fluorine" [1] was introduced by Dunitz and Taylor in 1997 to identify the C–F bonds in organic systems. Different research groups have used the phrase to glorify or deny the influence of C–F bond in crystal lattices. Once Dunitz stated that "Organic Fluorine: Odd Man Out" and Howard et al. questioned the role of "Organic fluorine" in crystal engineering. While some researchers have refuted the role of "organic fluorine" in crystal packing; the others indicated the importance of the interactions involving the same group. A number of publications have shown the importance of "Organic fluorine" in influencing crystal packing. We have been interested in the area of weak interactions in organic solid state chemistry since 1999 [2]; especially interactions involving "Organic fluorine". The study is being conducted following a systematic approach and is still in progress. We have looked at the structures of a number if tetrahydroisoquinoline derivatives, a number of differently substituted imines, phenyleacetanilydes, benzanilides and azobenzenes [3] etc. in order to elucidate the influence of "Organic fluorine" in crystal engineering both in the presence and in the absence of strong hydrogen bonding functional groups present within the molecule. A short summary of our observations will be highlighted in the presentation.

Los estilos APA, Harvard, Vancouver, ISO, etc.

30

Sonina, Alina A., Darya S. Cheshkina y Maxim S. Kazantsev. "Additive-Assisted Crystallization of 9,10-Diphenylanthracene". Crystals 13, n.º 6 (24 de mayo de 2023): 861. http://dx.doi.org/10.3390/cryst13060861.

Texto completo

Resumen

Crystallization control of organic conjugated small molecules is in high demand for the engineering of functional materials in organic optoelectronics. Here, we report solution additive-assisted crystallization of a model non-planar aromatic hydrocarbon derivative 9,10-diphenylanthracene. Among the studied series of related aromatic hydrocarbons comprising pyrene, perylene, anthracene, tetracene, and rubrene, only tetracene revealed clear reproducible effects allowing one to perform selective crystallization of metastable 9,10-diphenylanthracene polymorphs. Additionally, crystallization of 9,10-diphenylanthracene and pyrene produced a stoichiometric co-crystal (PYR–DPA) having a segregated layered molecular packing with alternating 9,10-diphenylanthracene and pyrene layers. Remarkably, the molecular packing of pyrene within the co-crystal is unique and represented by the herringbone motif, whereas the molecular packing in known pyrene polymorphs is represented by π-stacked molecules. The co-crystal also demonstrated a bright photoluminescence with a photoluminescence quantum yield of 51%. Considering the morphology of 9,10-diphenylanthracene crystals obtained and crystal structures of PYR–DPA co-crystal and tetracene, we have proposed the mechanism of additive-assisted polymorphism based on the inhibition of (111) facet of α-DPA and promoting of the layered structure crystallization corresponding to metastable polymorphs (β- and γ-DPA). We highlight the additive-assisted crystallization approach as a powerful tool for the crystal engineering of functional materials for organic optoelectronics.

Los estilos APA, Harvard, Vancouver, ISO, etc.

31

Cvetkovski, Aleksandar. "The Challenge for Engineering Pharmaceutical Crystalline Solids: Scientific and Regulatory Affairs Perspectives for Crystal Structure Design and Prediction". International Journal of Contemporary Research and Review 11, n.º 11 (9 de noviembre de 2020): 20201–10. http://dx.doi.org/10.15520/ijcrr.v11i11.859.

Texto completo

Resumen

The Breakthrough into solid-state research has become emerging approach for structure determination of Active Pharmaceutical Ingredients (APIs) and excipeents that consequently influence their physic-chemical properties, biopharmaceutical and pharmacokinetic profiles. The concept of conventional pharmaceutical salts has been extended to multicomponent crystals which diversity in nature of the non-covalent intermolecular interactions determine the crystal packing patterns within the structures, and thus modulate the native properties of APIs. Therefore, the aim of this review is to highlight how accomplishments in crystallographic research on molecular crystal have influenced their classification and how these new solid phases have been recognized by the regulatory bodies. The advantage to explore the pharmaceutical crystalline solids of one API implies the selection of the form with favorable properties for the development of formulations for pharmaceutical dosage forms.

Los estilos APA, Harvard, Vancouver, ISO, etc.

32

Dost, Sadik. "Recent Developments in Modeling of Liquid Phase Electroepitaxy: A Continuum Approach". Applied Mechanics Reviews 49, n.º 12 (1 de diciembre de 1996): 477–95. http://dx.doi.org/10.1115/1.3101920.

Texto completo

Resumen

Liquid phase electroepitaxy (LPEE) is a low temperature, solution growth technique which has been proven to be successful in growing high quality, thick compound and alloy semiconducting single crystal layers. The availability of such high quality alloy layers would open new horizons in the production of optoelectronic and high-speed devices. Due to the technological importance of this crystal growth technique, some theoretical models for its growth process have been developed recently to provide needed information to experimentalists to develop growth configurations for reproducible desired single crystals. These models have shed light on various aspects of the LPEE growth process. This review article, with 71 references, provides the reader with an overview of recently developed macroscopic continuum models for the LPEE growth process of binary and ternary semiconductors. Fundamental equations of these models are obtained from the basic principles of electrodynamics and thermomechanics of the continuum. The models include various thermoelectric effects observed in LPEE and also incorporates microscopic surface phenomena such as surface kinetics. Results of numerical simulations are presented, and compared with available experimental data. The significance of research results are discussed.

Los estilos APA, Harvard, Vancouver, ISO, etc.

33

Qazi, M. J., H. Salim, C. A. W. Doorman, E. Jambon-Puillet y N. Shahidzadeh. "Salt creeping as a self-amplifying crystallization process". Science Advances 5, n.º 12 (diciembre de 2019): eaax1853. http://dx.doi.org/10.1126/sciadv.aax1853.

Texto completo

Resumen

Salt creeping is a ubiquitous phenomenon in which crystals precipitate far from an evaporating salt solution boundary, which constitutes a major problem in outdoor electronics, civil engineering, artworks, and agriculture. We report a novel experimental approach that allows to quantitatively describe the creeping mechanism and demonstrate its universality with respect to different salts. We show that there exists a critical contact angle below which salt creeping occurs, provided also the nucleation of multiple crystals is favored. The precipitation of new crystals happens ahead of the contact line by the meniscus that progressively advances over the crystals forming also nanometric precursor films. This enlarges the evaporative area, causing an exponential increase in the crystal mass in time. The self-amplifying process then results in a spectacular three-dimensional crystal network at macroscopic distances from the solution reservoir. These findings also allow us to control the creeping by using crystallization modifiers.

Los estilos APA, Harvard, Vancouver, ISO, etc.

34

Cazacu, Oana y Ioan R. Ionescu. "Dynamic crystal plasticity: An Eulerian approach". Journal of the Mechanics and Physics of Solids 58, n.º 6 (junio de 2010): 844–59. http://dx.doi.org/10.1016/j.jmps.2010.04.001.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

35

Bardella, Fernando, Andre Montes Rodrigues y Ricardo Mendes Leal Neto. "CrystalWalk: crystal structures, step by step". Journal of Applied Crystallography 50, n.º 3 (25 de mayo de 2017): 949–50. http://dx.doi.org/10.1107/s160057671700560x.

Texto completo

Resumen

CrystalWalk is a crystal editor and visualization software designed for teaching materials science and engineering. Based on WebGL/HTML5, it provides an accessible and interactive platform to students and teachers by introducing a simplified crystallographic approach that creates crystal structures by combining a lattice with a motif without the use of its internal symmetry. CrystalWalk is the first software to use solely translational symmetry, aiming to introduce engineering students to the basic concepts of lattice and motif. Although very restrictive from the crystallographic point of view, CrystalWalk makes it simple for students to experiment, reproduce and visualize, in an interactive manner, most of the crystal structures that are commonly introduced in materials science and engineering curricula.

Los estilos APA, Harvard, Vancouver, ISO, etc.

36

Caginalp, G. "A mathematical approach to crystal growth". Superlattices and Microstructures 3, n.º 6 (enero de 1987): 595–98. http://dx.doi.org/10.1016/0749-6036(87)90189-3.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

37

Belyakov, Vladimir A. "Optical Kossel Lines and Fluorescence in Photonic Liquid Crystals". Crystals 10, n.º 6 (24 de junio de 2020): 541. http://dx.doi.org/10.3390/cryst10060541.

Texto completo

Resumen

We propose a general analytical way to describe the fluorescence peculiarities in photonic liquid crystals (revealing themselves as an optical analog of the X-ray Kossel lines in conventional crystals) based at the localized optical edge modes existing in perfect photonic liquid crystal layers. The proposed approach allows us to predict theoretically the properties of optical Kossel lines in photonic liquid crystal (fluorescence polarization, spectral and angular fluorescence distribution, influence of the light absorption in liquid crystal, and, in particular, existing the optical Borrmann effect if the absorption in liquid crystal is locally anisotropic). Comparison of the theoretical results and the known experimental data shows that the theory reproduces sufficiently well the observation results on the fluorescence in photonic liquid crystals. For confirming a direct connection of the optical Kossel lines to the localized optical edge modes in perfect photonic liquid crystal, we propose the application of time-delayed techniques in studying the optical Kossel lines.

Los estilos APA, Harvard, Vancouver, ISO, etc.

38

Snyder, Ryan C. y Michael F. Doherty. "Predicting crystal growth by spiral motion". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 465, n.º 2104 (6 de enero de 2009): 1145–71. http://dx.doi.org/10.1098/rspa.2008.0234.

Texto completo

Resumen

We present a systematic modelling methodology using the spiral growth mechanism of Burton, Cabrera and Frank to predict the steady-state shape of organic molecular crystals grown from solution. This methodology has been developed to eliminate the need for special modifications for each new crystal system studied. Therefore, the mechanisms and choices for spiral shapes, edges and evolution are mathematically determined as governed by the underlying solid-state chemistry and physics. The power of the approach is demonstrated for several crystal systems: naphthalene grown from both ethanol and cyclohexane; anthracene grown from 2-propanol; and glycine grown from water. The predicted crystal shapes are in good agreement with experiment.

Los estilos APA, Harvard, Vancouver, ISO, etc.

39

Pekamwar, S. S., D. D. Gadade y G. K. Kale. "CO-CRYSTALLIZATION: TECHNIQUE FOR IMPROVEMENT OF PHARMACEUTICAL PROPERTIES". INDIAN DRUGS 53, n.º 09 (28 de septiembre de 2016): 5–11. http://dx.doi.org/10.53879/id.53.09.10454.

Texto completo

Resumen

Physicochemical characteristics of active pharmaceutical compounds, including solubility and flow properties, are crucial in the development of drug formulation. The physical form of compound and formulation has potential effect on biopharmaceutical parameters of the drug. The crystal engineering approach can be employed for modification of physicochemical properties of the active pharmaceutical ingredients whilst maintaining the intrinsic activity of the drug molecule. This article covers the advantages of co-crystals over salts, solvates (hydrates), solid dispersions and polymorphs, mechanism of formation of co-crystals, methods of preparation of co-crystals and application of co-crystals to modify physicochemical characteristics of active pharmaceutical ingredients along with case studies.

Los estilos APA, Harvard, Vancouver, ISO, etc.

40

Ermanova, Inga, Narges Yaghoobi Nia, Enrico Lamanna, Elisabetta Di Bartolomeo, Evgeny Kolesnikov, Lev Luchnikov y Aldo Di Carlo. "Crystal Engineering Approach for Fabrication of Inverted Perovskite Solar Cell in Ambient Conditions". Energies 14, n.º 6 (22 de marzo de 2021): 1751. http://dx.doi.org/10.3390/en14061751.

Texto completo

Resumen

In this paper, we demonstrate the high potentialities of pristine single-cation and mixed cation/anion perovskite solar cells (PSC) fabricated by sequential method deposition in p-i-n planar architecture (ITO/NiOX/Perovskite/PCBM/BCP/Ag) in ambient conditions. We applied the crystal engineering approach for perovskite deposition to control the quality and crystallinity of the light-harvesting film. The formation of a full converted and uniform perovskite absorber layer from poriferous pre-film on a planar hole transporting layer (HTL) is one of the crucial factors for the fabrication of high-performance PSCs. We show that the in-air sequential deposited MAPbI3-based PSCs on planar nickel oxide (NiOX) permitted to obtain a Power Conversion Efficiency (PCE) exceeding 14% while the (FA,MA,Cs)Pb(I,Br)3-based PSC achieved 15.6%. In this paper we also compared the influence of transporting layers on the cell performance by testing material depositions quantity and thickness (for hole transporting layer), and conditions of deposition processes (for electron transporting layer). Moreover, we optimized second step of perovskite deposition by varying the dipping time of substrates into the MA(I,Br) solution. We have shown that the layer by layer deposition of the NiOx is the key point to improve the efficiency for inverted perovskite solar cell out of glove-box using sequential deposition method, increasing the relative efficiency of +26% with respect to reference cells.

Los estilos APA, Harvard, Vancouver, ISO, etc.

41

Noh, D. y J. W. Yoon. "Reduced texture approach for crystal plasticity finite element method toward macroscopic engineering applications". IOP Conference Series: Materials Science and Engineering 967 (19 de noviembre de 2020): 012071. http://dx.doi.org/10.1088/1757-899x/967/1/012071.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

42

Mercier, Gabriel M., Koen Robeyns y Tom Leyssens. "Altering the Photochromic Properties of N-Salicylideneanilines Using a Co-Crystal Engineering Approach". Crystal Growth & Design 16, n.º 6 (18 de mayo de 2016): 3198–205. http://dx.doi.org/10.1021/acs.cgd.6b00108.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

43

Liu, Jun Jie, Yangzong Qin, Maya Bar Dolev, Yeliz Celik, J. S. Wettlaufer y Ido Braslavsky. "Modelling the influence of antifreeze proteins on three-dimensional ice crystal melt shapes using a geometric approach". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, n.º 2147 (27 de junio de 2012): 3311–22. http://dx.doi.org/10.1098/rspa.2011.0720.

Texto completo

Resumen

The melting of pure axisymmetric ice crystals has been described previously by us within the framework of so-called geometric crystal growth . Non-equilibrium ice crystal shapes evolving in the presence of hyperactive antifreeze proteins (hypAFPs) are experimentally observed to assume ellipsoidal geometries (‘lemon’ or ‘rice’ shapes). To analyse such shapes, we harness the underlying symmetry of hexagonal ice I h and extend two-dimensional geometric models to three-dimensions to reproduce the experimental dissolution process. The geometrical model developed will be useful as a quantitative test of the mechanisms of interaction between hypAFPs and ice.

Los estilos APA, Harvard, Vancouver, ISO, etc.

44

von Wolff, Lars, Felix Weinhardt, Holger Class, Johannes Hommel y Christian Rohde. "Investigation of Crystal Growth in Enzymatically Induced Calcite Precipitation by Micro-Fluidic Experimental Methods and Comparison with Mathematical Modeling". Transport in Porous Media 137, n.º 2 (24 de febrero de 2021): 327–43. http://dx.doi.org/10.1007/s11242-021-01560-y.

Texto completo

Resumen

AbstractEnzymatically induced calcite precipitation (EICP) is an engineering technology that allows for targeted reduction of porosity in a porous medium by precipitation of calcium carbonates. This might be employed for reducing permeability in order to seal flow paths or for soil stabilization. This study investigates the growth of calcium-carbonate crystals in a micro-fluidic EICP setup and relies on experimental results of precipitation observed over time and under flow-through conditions in a setup of four pore bodies connected by pore throats. A phase-field approach to model the growth of crystal aggregates is presented, and the corresponding simulation results are compared to the available experimental observations. We discuss the model’s capability to reproduce the direction and volume of crystal growth. The mechanisms that dominate crystal growth are complex depending on the local flow field as well as on concentrations of solutes. We have good agreement between experimental data and model results. In particular, we observe that crystal aggregates prefer to grow in upstream flow direction and toward the center of the flow channels, where the volume growth rate is also higher due to better supply.

Los estilos APA, Harvard, Vancouver, ISO, etc.

45

Lee, Alfred Y. y Allan S. Myerson. "Particle Engineering: Fundamentals of Particle Formation and Crystal Growth". MRS Bulletin 31, n.º 11 (noviembre de 2006): 881–86. http://dx.doi.org/10.1557/mrs2006.207.

Texto completo

Resumen

AbstractThe engineering of particles with customized properties optimized for dosage form manufacture (tablet, capsule, ointment, etc.) has long been a goal of the pharmaceutical industry. Particles can be designed through modification in the size, morphology, and packing arrangement of the solids. The most common approach in achieving this is through crystallization. In this bottom-up process, the two main steps, nucleation and crystal growth, both play a decisive role in shaping the quality of the final crystalline product. In this review, the role of nucleation and crystal growth in controlling particle properties is discussed, and examples are provided that demonstrate the variation in solid-state properties as a function of size, habit (morphology), and internal structure of the particles. In addition, the role of particle properties in product performance and dosage form development of pharmaceuticals is also discussed.

Los estilos APA, Harvard, Vancouver, ISO, etc.

46

Sudha, N., S. Anbuselvi, Sudhakar Jyothula, A. Thiruppathi, B. Vijayakumar, Kartikeya Parmar, G. Puthilibai y Leevesh Kumar. "Synthesis, Structural, Spectroscopic, and Hirshfeld Surface Analysis, and DFT Investigation of Benzaldehyde Semicarbazone". Advances in Materials Science and Engineering 2022 (16 de junio de 2022): 1–14. http://dx.doi.org/10.1155/2022/4091119.

Texto completo

Resumen

By using slow evaporation, single crystals of BDSC (chemical name: 2-benzylidenehydrazine carboxamide) have been formed. A slow evaporation approach was used to generate BDSC single crystals. By using single-crystal XRD, the nonlinear characteristics of the material were studied. The presence of molecular groups was carefully examined using fundamental vibrational analysis. A Hirshfeld analysis was used to study the interactions between molecules. A series of UV-visible, photoluminescence, and VCD spectroscopic experiments were used to verify the optical characteristics of the material. In order to determine the electrical characteristics, dielectric investigations were carried out. Tests of Vickers hardness were used to measure mechanical strength. The SHG behaviour of the crystal was determined using the Kurtz–Perry method. To assess the molecule’s thermal stability, all quantitative calculations were performed using the B3LYP approach with a basis function of 6-31 + G(d,p) and TG/DTA experiments.

Los estilos APA, Harvard, Vancouver, ISO, etc.

47

Zhang, Liangzhe, Rémi Dingreville, Timothy Bartel y Mark T. Lusk. "A stochastic approach to capture crystal plasticity". International Journal of Plasticity 27, n.º 9 (septiembre de 2011): 1432–44. http://dx.doi.org/10.1016/j.ijplas.2011.04.002.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

48

Honjo, S., M. J. Cima, M. C. Flemings, T. Ohkuma, H. Shen, K. Rigby y T. H. Sung. "Seeded Crystal Growth of Yba2Cu3O6.5 in Semisolid Melts". Journal of Materials Research 12, n.º 4 (abril de 1997): 880–90. http://dx.doi.org/10.1557/jmr.1997.0128.

Texto completo

Resumen

Melt textured single crystals of YBa2Cu3O6.5 (123) superconductors were produced by isothermal solidification from a semisolid melt using single crystal NdBa2Cu3O6.5 or SmBa2Cu3O6.5 seeds. The microstructure within the single crystals shows an inhomogeneous segregation of Y2BaCO5 (211) particles trapped in the 123 crystals during solidification. The concentration of 211 particles varies with the crystal axes in 123 crystals produced from precursors with compositions of 80 wt.% 123 powder and 20 wt.% excess 211. The 211 particle concentration along the c-axis in the crystal is much lower than that along the a- or b-axes during initial crystallization. This concentration increases in both directions as the crystal grows larger. The 211 concentration along the c-axis increases more quickly than the concentration along the other axes during solidification, which allows the 211 concentration to approach that on the other axes as the solidification continues. 211 particle segregation in stoichiometric 123 samples formed “X”-shaped tracks instead of the variations in 211 concentration described above. A single crystal growth model of 123 is proposed and employed to interpret these experimental observations. Quenched samples were prepared to investigate the volume fraction of 211 particles in the liquid phase. A constant distribution of 211 particles was observed in the liquid, except very near the crystal interface, where the 211 concentration decreased rapidly. Copper oxide content in the liquid was also measured. It is found that the copper content is lower at the (001) interface compared with (100) or (010) interfaces.

Los estilos APA, Harvard, Vancouver, ISO, etc.

49

Tanida, S., N. Takata, R. Takano, A. Sakon, T. Ueto, K. Shiraki, K. Kadota, Y. Tozuka y M. Ishigai. "Cocrystal structure design for CH5134731 based on isomorphism". CrystEngComm 20, n.º 3 (2018): 362–69. http://dx.doi.org/10.1039/c7ce01878a.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

50

McArthur, John B. y Xi Chen. "Glycosyltransferase engineering for carbohydrate synthesis". Biochemical Society Transactions 44, n.º 1 (9 de febrero de 2016): 129–42. http://dx.doi.org/10.1042/bst20150200.

Texto completo

Resumen

Glycosyltransferases (GTs) are powerful tools for the synthesis of complex and biologically-important carbohydrates. Wild-type GTs may not have all the properties and functions that are desired for large-scale production of carbohydrates that exist in nature and those with non-natural modifications. With the increasing availability of crystal structures of GTs, especially those in the presence of donor and acceptor analogues, crystal structure-guided rational design has been quite successful in obtaining mutants with desired functionalities. With current limited understanding of the structure–activity relationship of GTs, directed evolution continues to be a useful approach for generating additional mutants with functionality that can be screened for in a high-throughput format. Mutating the amino acid residues constituting or close to the substrate-binding sites of GTs by structure-guided directed evolution (SGDE) further explores the biotechnological potential of GTs that can only be realized through enzyme engineering. This mini-review discusses the progress made towards GT engineering and the lessons learned for future engineering efforts and assay development.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Artículos de revistas sobre el tema "Crystal Engineering Approach"

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros