Shipping of water on a two-dimensional structure. Part 2

2007 ◽  
Vol 581 ◽  
pp. 371-399 ◽  
Author(s):  
M. GRECO ◽  
G. COLICCHIO ◽  
O. M. FALTINSEN
Keyword(s):  
Three Dimensional ◽  
Quantitative Information ◽  
Front Velocity ◽  
Green Water ◽  
Dimensional Structure ◽  
Two Dimensional ◽  
Incoming Wave ◽  
Water On Deck ◽  
Type Water ◽  
Water Front

The water-shipping problem is modelled in a two-dimensional framework and studied experimentally and numerically for the case of a fixed barge-shaped structure. The analysis represents the second step of the research discussed in Greco et al. (J. Fluid Mech., vol. 525, 2005, p. 309). The numerical investigation is performed by using both a boundary element method and a domain-decomposition strategy. The model tests highlight the occurrence of dam-breaking-type water on deck, (a) with and (b) without an initial plunging phase, and (c) an unusual type of water shipping connected with blunt water–deck impacts here called a hammer-fist type event never documented before. Cases (a) and (c) are connected with the most severe events and the related features and green-water loads are discussed in detail. A parametric analysis of water-on-deck phenomena has also been carried out in terms of the local incoming waves and bow flow features. We classify such phenomena in a systematic way to provide a basis for further investigations of water-on-deck events. The severity of (a)-type water-on-deck events is analysed in terms of initial cavity area and water-front velocity along the deck. The former increases as the square power of the modified incoming-wave (front-crest) steepness while the latter scales with its square-root. The two-dimensional investigation gives useful quantitative information in terms of water-front velocity for comparison with three-dimensional water-on-deck experiments on fixed bow models interacting with wave packets.

Three-Dimensional Structure of Cloned T3 Connector Protein at 1.6nm Resolution

1990 ◽  
Vol 48 (1) ◽  
pp. 282-283
Author(s):  
José L. Carrascosa ◽  
José M. Valpuesta ◽  
Hisao Fujisawa
Keyword(s):  
Dna Sequences ◽  
Expression Vector ◽  
Three Dimensional ◽  
Deae Cellulose ◽  
Dna Packaging ◽  
Dimensional Structure ◽  
Two Dimensional ◽  
Freezing And Thawing ◽  
Three Dimensional Structure ◽  
Dimensional Reconstruction

The head to tail connector of bacteriophages plays a fundamental role in the assembly of viral heads and DNA packaging. In spite of the absence of sequence homology, the structure of connectors from different viruses (T4, Ø29, T3, P22, etc) share common morphological features, that are most clearly revealed in their three-dimensional structure. We have studied the three-dimensional reconstruction of the connector protein from phage T3 (gp 8) from tilted view of two dimensional crystals obtained from this protein after cloning and purification.DNA sequences including gene 8 from phage T3 were cloned, into Bam Hl-Eco Rl sites down stream of lambda promotor PL, in the expression vector pNT45 under the control of cI857. E R204 (pNT89) cells were incubated at 42°C for 2h, harvested and resuspended in 20 mM Tris HC1 (pH 7.4), 7mM 2 mercaptoethanol, ImM EDTA. The cells were lysed by freezing and thawing in the presence of lysozyme (lmg/ml) and ligthly sonicated. The low speed supernatant was precipitated by ammonium sulfate (60% saturated) and dissolved in the original buffer to be subjected to gel nitration through Sepharose 6B, followed by phosphocellulose colum (Pll) and DEAE cellulose colum (DE52). Purified gp8 appeared at 0.3M NaCl and formed crystals when its concentration increased above 1.5 mg/ml.

Numerical Research on FPSOs With Green Water Occurrence

2009 ◽  
Vol 53 (01) ◽  
pp. 7-18
Author(s):  
Renchuan Zhu ◽  
Guoping Miao ◽  
Zhaowei Lin
Keyword(s):  
Three Dimensional ◽  
Green Water ◽  
Floating Body ◽  
Incoming Wave ◽  
Model Case ◽  
Floating Structures ◽  
Design And Optimization ◽  
Head Waves ◽  
Wave Heights ◽  
The Impact

Green water loads on sailing ships or floating structures occur when an incoming wave significantly exceeds freeboard and water runs onto the deck. In this paper, numerical programs developed based on the platform of the commercial software Fluent were used to numerically model green water occurrence on floating structures exposed to waves. The phenomena of the fixed floating production, storage, and offloading unit (FPSO) model and oscillating vessels in head waves have been simulated and analyzed. For the oscillating floating body case, a combination idea is presented in which the motions of the FPSO are calculated by the potential theory in advance and computional fluid dynamics (CFD) tools are used to investigate the details of green water. A technique of dynamic mesh is introduced in a numerical wave tank to simulate the green water occurrence on the oscillating vessels in waves. Numerical results agree well with the corresponding experimental results regarding the wave heights on deck and green water impact loads; the two-dimensional fixed FPSO model case conducted by Greco (2001), and the three-dimensional oscillating vessel cases by Buchner (2002), respectively. The research presented here indicates that the present numerical scheme and method can be used to actually simulate the phenomenon of green water on deck, and to predict and analyze the impact forces on floating structures due to green water. This can be of great significance in further guiding ship design and optimization, especially in the strength design of ship bows.

scholarly journals Mechanochemical Synthesis of a Mercury(II) Metal-Organic Framework Reveals a Two-Dimensional Polymorph Stabilized by Weak Interactions

2019 ◽  
Author(s):  
Isaiah R. Speight ◽  
Igor Huskić ◽  
Mihails Arhangelskis ◽  
Hatem M. Titi ◽  
Robin Stein ◽  
...  
Keyword(s):  
Density Functional ◽  
Weak Interactions ◽  
Metal Organic Framework ◽  
Three Dimensional ◽  
Density Functional Theory Calculations ◽  
Dimensional Structure ◽  
Reaction Monitoring ◽  
Two Dimensional ◽  
Functional Theory ◽  
Metal Organic

Solid-state mechanochemistry revealed a novel polymorph of the mercury(II) imidazolate framework, based on square-grid (sql) topology layers. Reaction monitoring and periodic density functional theory calculations show that the sql-structure is of higher stability than the previously reported three-dimensional structure, with the unexpected stabilization of a lower dimensionality structure explained by contributions of weak interactions, which include short C-H···Hg contacts.

Poly[deca-μ2-cyanido-dicyanidobis(μ2-ethylenediamine)bis(ethylenediamine)tricadmium(II)dicobalt(III)]: a two-dimensional coordination polymer

2009 ◽  
Vol 65 (3) ◽  
pp. m118-m120
Author(s):  
Olha Sereda ◽  
Helen Stoeckli-Evans
Keyword(s):  
Coordination Polymer ◽  
Network Structure ◽  
General Position ◽  
Rotation Axis ◽  
Three Dimensional ◽  
The Other ◽  
Dimensional Structure ◽  
Two Dimensional ◽  
Asymmetric Unit ◽  
Dimensional Network

The title coordination polymer, [Cd3Co2(CN)12(C2H8N2)4]n, has an infinite two-dimensional network structure. The asymmetric unit is composed of two crystallographically independent CdIIatoms, one of which is located on a twofold rotation axis. There are two independent ethylenediamine (en) ligands, one of which bis-chelates to the Cd atom that sits in a general position, while the other bridges this Cd atom to that sitting on the twofold axis. The Cd atom located on the twofold rotation axis is linked to four equivalent CoIIIatomsviacyanide bridges, while the Cd atom that sits in a general position is connected to three equivalent CoIIIatomsviacyanide bridges. In this way, a series of trinuclear, tetranuclear and pentanuclear macrocycles are linked to form a two-dimensional network structure lying parallel to thebcplane. In the crystal structure, these two-dimensional networks are linkedviaN—H...N hydrogen bonds involving an en NH2H atom and a cyanide N atom, leading to the formation of a three-dimensional structure. This coordination polymer is only the second example involving a cyanometallate where the en ligand is present in both chelating and bridging coordination modes.

A new two-dimensional managnese(II) coordination polymer constructed by 2,2′-(1,2-phenylene)bis(1H-imidazole-4,5-dicarboxylate)

2018 ◽  
Vol 74 (5) ◽  
pp. 599-603 ◽  
Author(s):  
Yan-Ju Liu ◽  
Di Cheng ◽  
Ya-Xue Li ◽  
Xiang-Ru Meng ◽  
Huai-Xia Yang
Keyword(s):  
Solid State ◽  
Coordination Polymer ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Coordination Geometry ◽  
Two Dimensional ◽  
Carboxylate Ligands ◽  
Rich Variety ◽  
Distorted Octahedral ◽  
Solvothermal Conditions

In recent years, N-heterocyclic carboxylate ligands have attracted much interest in the preparation of new coordination polymers since they contain N-atom donors, as well as O-atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. A new two-dimensional coordination polymer, namely poly[[μ3-2,2′-(1,2-phenylene)bis(4-carboxy-1H-imidazole-5-carboxylato)-κ6 O 4,N 3,N 3′,O 4′:O 5:O 5′]manganese(II)], [Mn(C16H8N4O8)] n or [Mn(H4Phbidc)] n , has been synthesized by the reaction of Mn(OAc)2·4H2O (OAc is acetate) with 2,2′-(1,2-phenylene)bis(1H-imidazole-4,5-dicarboxylic acid) (H6Phbidc) under solvothermal conditions. In the polymer, each MnII ion is six-coordinated by two N atoms from one H4Phbidc2− ligand and by four O atoms from three H4Phbidc2− ligands, forming a significantly distorted octahedral MnN2O4 coordination geometry. The MnII ions are linked by hexadentate H4Phbidc2− ligands, leading to a two-dimensional structure parallel to the ac plane. In the crystal, adjacent layers are further connected by N—H...O hydrogen bonds, forming a three-dimensional structure in the solid state.

scholarly journals Structural diversity induced by ligand geometry: From two-dimensional to three-dimensional coordination polymers with pyridine

2020 ◽  
pp. 174751982096816
Author(s):  
Fang-Kuo Wang ◽  
Shi-Yao Yang ◽  
Hua-Ze Dong
Keyword(s):  
Coordination Polymers ◽  
Three Dimensional ◽  
Structural Diversity ◽  
Dimensional Structure ◽  
Layer By Layer ◽  
Two Dimensional ◽  
Guest Molecules ◽  
X Ray ◽  
Benzenedicarboxylic Acid ◽  
Benzenetricarboxylic Acid

Two coordination polymers with two-dimensional and three-dimensional structures are, {[Zn3(bdc)3(py)2]·2NMP}n (1) (H2bdc = 1,4-benzenedicarboxylic acid) and [Zn2(NO3−)(btc)(nmp)2(py)]n (2) (H3btc = 1,3,5-benzenetricarboxylic acid), synthesized by hot-solution reactions of Zn(NO3)2·6H2O, pyridine (py) and two different ligands in N-methylpyrrolidone (NMP). {[Zn3(bdc)3(py)2]·2NMP}n exhibits two-dimensional networks with trizinc subunits [Zn3(COO)6py2] stacking with a layer-by-layer alignment, and there are strong π–π interactions involving py from adjacent layers. [Zn2(NO3−)(btc)(nmp)2(py)]n has a three-dimensional structure containing two independent zinc ions, tetrahedral ZnO4 and octahedral ZnNO5. Based on X-ray studies, the coordination polymers {[Zn3(bdc)3(py)2]·2NMP}n (1) have a porous structure with NMP guest molecules. In contrast, X-ray studies revealed that coordination polymer [Zn2(NO3−)(btc)(nmp)2(py)]n (2) had a larger void that was inhabited by coordinated py and NMP. In addition, the form of the two coordination polymers changed from two-dimensional to three-dimensional with transformation of the ligand geometry.

scholarly journals Crystal structure ofcatena-poly[bis(formato-κO)bis[μ2-1,1′-(1,4-phenylene)bis(1H-imidazole)-κ2N3:N3′]cobalt(II)]

2015 ◽  
Vol 71 (9) ◽  
pp. m156-m157
Author(s):  
Guo-Wang Xu ◽  
Ye-Nan Wang ◽  
Hong-Xu Xia ◽  
Zhong-Long Wang
Keyword(s):  
Crystal Structure ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Supramolecular Network ◽  
Nitrate Hexahydrate ◽  
Coordination Geometry ◽  
Two Dimensional ◽  
Asymmetric Unit ◽  
Hydrogen Bonding Interactions ◽  
Block Shaped Crystal

A red block-shaped crystal of the title compound, [Co(HCOO)2(C12H10N4)2]n, was obtained by the reaction of cobalt(II) nitrate hexahydrate, formic acid and 1,1′-(1,4-phenylene)bis(1H-imidazole) (bib) molecules. The asymmetric unit consists of one CoIIcation, one formate ligand and two halves of a bib ligand. The central CoIIcation, located on an inversion centre, is coordinated by two carboxylate O atoms and four N atoms from bib ligands, completing an octahedral coordination geometry. The CoIIcentres are bridged by bib ligands, giving a two-dimensional net. Topologically, taking the CoIIatoms as nodes and the bib ligands as linkers, the two-dimensional structure can be simplified as a typicalsql/Shubnikov tetragonal plane network. The structure features C—H...O hydrogen-bonding interactions between formate and bib ligands, resulting in a three-dimensional supramolecular network.

Sign in / Sign up

Export Citation Format

Share Document