Systematic investigation of the relationships between 25 crystal structures containing the carbamazepine molecule or a close analogue: a case study of the XPac method

CrystEngComm ◽  
2006 ◽  
Vol 8 (6) ◽  
pp. 448 ◽  
Author(s):  
Thomas Gelbrich ◽  
Michael B. Hursthouse
Keyword(s):  
Crystal Structures ◽  
Systematic Investigation ◽  
Close Analogue

Systematic investigation of non-conformance root cause in prefabrication: a nuclear case study

2021 ◽  
Author(s):  
Steven Chuo ◽  
Qian Chen ◽  
Mohammad Mahdi Sharif ◽  
Carl T. Haas ◽  
Bryan T. Adey
Keyword(s):  
Systematic Investigation ◽  
Root Cause

A systematic investigation of structural transformation in a copper pyrazolato system: a case study

2020 ◽  
Vol 49 (4) ◽  
pp. 1116-1123 ◽  
Author(s):  
Jing-Huo Chen ◽  
Donghui Wei ◽  
Guang Yang ◽  
Jian-Gong Ma ◽  
Peng Cheng
Keyword(s):  
Structural Transformation ◽  
Mixed Valence ◽  
Systematic Investigation ◽  
Structural Conversion ◽  
System A

The mixed-valence CuI3CuII2(OMe)2pz5 has been isolated as a possible key intermediate in the structural conversion from (CuIpz)3/(CuIpz)4 to cyclic hexanuclear CuII species.

Stern Flap for Resistance Reduction of Planing Hull Craft: A Case Study with a Fast Crew Boat Model

2012 ◽  
Author(s):  
Omar Yaakob ◽  
Suhaili Shamsuddin ◽  
Kho King Koh
Keyword(s):  
Reduction Rate ◽  
Cost Effective ◽  
Systematic Investigation ◽  
Percent Reduction ◽  
Geometrical Characteristics ◽  
Resistance Reduction ◽  
Cost Effective Method ◽  
Zero Degree ◽  
Resistance Performance

Kajian terhadap pelbagai cara mengurangkan rintangan bot peronda telah dilakukan oleh ramai penyelidik. Kaedah yang dikaji termasuk penggunaan kepak buritan, baji buritan dan suntikan gelembung mikro. Walau bagaimanapun, disebabkan oleh sifatnya yang mudah dan praktikal, kepak buritan didapati amat berpotensi. Kertas kerja ini membentangkan kajian terhadap kesan kepak buritan terhadap prestasi rintangan bot kelasi berbentuk planing. Ujian model dijalankan bagi membuktikan keberkesanan kepak bagi mengurangkan rintangan. Lima kepak berlainan telah digunakan dalam rangka kajian sistematik bagi menentukan ciri geometrik optimum kepak buritan. Hasil ujian model menunjukkan empat kepak menambah rintangan kapal manakala kepak kelima pada sudut sifar mengurangkan rintangan sehingga 7.2 peratus pada 23 knots dan pengurangan purata sekitar 4.5 peratus. Pada 23 knots, pengurangan 8.2 peratus kuasa berkesan diperolehi. Kata kunci: Reka bentuk bot peronda, ujian model, pesawat laju The study on various methods of reducing the resistance of patrol craft have been carried out by many researchers. These methods included the application of stern flaps, stern wedges, and microbubble injection. However, due to its simplicity and practicality, stern flap is the most promising and cost effective method. The effect of a stern flap on the resistance performance of the planing hull crew boat is presented. Model tests were conducted to prove the effectiveness of the stern flap on reducing planing hull craft resistance. Five different stern flap designs were tested as part of systematic investigation to determine the optimum geometrical characteristics of the stern flap. Results of model resistance experiments showed that four of the flaps tested showed an increase in resistance while the flap at zero degree angle reduced the total resistance by 7.2 percent at 23 knots, and an average reduction rate of 4.5 percent. At 23 knots, an 8.2 percent reduction in effective power was predicted. Key words: Patrol boats design, model testing, fast craft

scholarly journals Global search for low-lying crystal structures using the artificial force induced reaction method: A case study on carbon

2017 ◽  
Vol 95 (18) ◽  
Author(s):  
Makito Takagi ◽  
Tetsuya Taketsugu ◽  
Hiori Kino ◽  
Yoshitaka Tateyama ◽  
Kiyoyuki Terakura ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Global Search ◽  
Reaction Method ◽  
Induced Reaction

Hydrogen bonding in enantiomeric versus racemic mono-carboxylic acids; a case study of 2-phenoxypropionic acid

2003 ◽  
Vol 59 (1) ◽  
pp. 132-140 ◽  
Author(s):  
Henning Osholm Sørensen ◽  
Sine Larsen
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Crystal Structures ◽  
Carboxylic Acids ◽  
Crystal Packing ◽  
Cyclic Dimer ◽  
Optically Pure ◽  
Pure Enantiomer ◽  
Hydrogen Bonded

The structural and thermodynamic backgrounds for the crystallization behaviour of racemates have been investigated using 2-phenoxypropionic acid (PPA) as an example. The racemate of PPA behaves normally and forms a racemic compound that has a higher melting point and is denser than the enantiomer. Low-temperature crystal structures of the pure enantiomer, the enantiomer cocrystallized with n-alkanes and the racemic acid showed that hydrogen-bonded dimers that form over crystallographic symmetry elements exist in all but the structure of the pure enantiomer. A database search for optically pure chiral mono-carboxylic acids revealed that the hydrogen-bonded cyclic dimer is the most prevalent hydrogen-bond motif in chiral mono-carboxylic acids. The conformation of PPA depends on the hydrogen-bond motif; the antiplanar conformation relative to the ether group is associated with a catemer hydrogen-bonding motif, whereas the more abundant synplanar conformation is found in crystals that contain cyclic dimers. Other intermolecular interactions that involve the substituent of the carboxylic group were identified in the crystals that contain the cyclic dimer. This result shows how important the nature of the substituent is for the crystal packing. The differences in crystal packing have been related to differences in melting enthalpy and entropy between the racemic and enantiomeric acids. In a comparison with the equivalent 2-(4-chlorophenoxy)-propionic acids, the differences between the crystal structures of the chloro and the unsubstituted acid have been identified and related to thermodynamic data.

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