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Hydrogen-bond mediated and concentrate-dependent NaHCO_(3) crystal morphology in NaHCO3–Na2CO3 aqueous solution: Experiments and computer simulations

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Chinese Journal of Chemical Engineering 2023年第3期55卷 49-58页

作者： Qiaoqiao Liu Guihong Lin Jian Zhou Liangliang Huang Chang Liu College of Chemical Engineering Nanjing Tech UniversityNanjing 210009China Zhangjiagang Institute of Nanjing Tech University Suzhou 215699China Guangdong Provincial Key Laboratory for Green Chemical Product Technology School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China School of Chemical Biological&Materials EngineeringUniversity of OklahomaNorman 73019United States

Adding Na_(2)CO_(3) to the NaHCO_(3) cooling crystallizer, using the common ion effect to promote crystallization and improve product morphology, is a new process recently proposed in the literature. However, the mechanism of the impact of Na_(2)CO_(3)on the crystal morphology is still indeterminate. In this work, the crystallization of NaHCO_(3)in water and Na_(2)CO_(3)–NaHCO_(3) aqueous solution was investigated by experiments and molecular dynamics simulations(MD). The crystallization results demonstrate that the morphology of NaHCO_(3) crystal changed gradually from needle-like to flake structure with the addition of Na_(2)CO_(3). The simulation results indicate that the layer docking model and the modified attachment energy formula without considering the roughness of crystal surface can obtain the crystal morphology in agreement with the experimental results, but the lower molecules of the crystal layer have to be fixed during MD. Thermodynamic calculation of the NaHCO_(3) crystallization process verifies that the common ion effect from Na^(+)and the ionization equilibrium transformation from CO_(3)^(2-) jointly promote the precipitation of NaHCO_(3) crystal. The radial distribution function analysis indicates that the oxygen atoms of Na_(2)CO_(3) formed strong hydrogen bonds with the hydrogen atoms of the(0 1 1) face, which weakened the hydration of water molecules at the crystal surface, resulting in a significant change in the attachment energy of this crystal surface. In addition, Na+and CO_(3)^(2-) are more likely to accumulate on the(011) face,resulting in the fastest growth rate on this crystal surface, which eventually leads to a change in crystal morphology from needle-like to flake-like.

关键词： NaHCO_(3) crystal morphology Hydrogen bond Molecular simulation

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Preparation of Ultrafine TATB and the Technology for crystal morphology Control

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Chinese Journal of Chemistry 2012年第2期30卷 293-298页

作者： Yang,Li Ren,Xiaoting Li,Tiecheng Wang,Shiwei Zhang,Tonglai State Key Laboratory of Explosion Seience and Technology Beijing Institute of TechnologyBeijing 100081China The 42nd Institute of the Fourth Academy of China Aerospace Science and Technology Corporation Xiangyang 441003China

The ultrafine 1,3,5-triamino-2,4,6-trinitrobenzene （TATB） has been prepared by using solvent and non-solvent method, and the influencing factors in close relationship with the grain size and crystal morphology control such as categories and dosage of surfactants, volume ratio of solvent to non-solvent have also been considered in this paper. It showed that these factors had remarkable effect on the crystal morphology, particle size and agglomeration during the crystallization process. By using 0.095% （mass percentage） ionic surfactant （S） as the additive and using spray-drops feeding device as the dropping equipment, 1.06 g TATB raw materials have been refined into free-running ellipsoid and spherical TATB grains with the grain size from 30 to 50 nm. By using 0.014% （mass percentage） non-ionic surfactant （P） as the additive, spherical TATB grains with the particle diameter of 50 nm and with narrow particle-size distribution have also been obtained. It was shown by the characterizations that the ultrafine particle of TATB had better heat resisting evenness and its 5 seconds ignition point is advanced by 7.5 K.

关键词： 1,3,5-triamino-2,4,6-trinitrobenzene solvent and non-solvent method ultrafine crystal morphology crystal growth surfactants

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Regulation mechanism of catalyst structure on diamond crystal morphology under HPHT process

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Chinese Physics B 2020年第7期29卷 555-559页

作者： Ya-Dong Li Yong-Shan Cheng Meng-Jie Su Qi-Fu Ran Chun-Xiao Wang Hong-An Ma Chao Fang Liang-Chao Chen College of Electronical Information Engineering Yangtze Normal UniversityChongqing 408100China State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012China Key Laboratory of Material Physics of Ministry of Education School of Physical EngineeringZhengzhou UniversityZhengzhou 450052China

To elucidate the regulation mechanism of catalyst geometry structure to diamond growth,we establish three catalyst modes with different *** simulation results show that with the decrease of the protruding height of the catalyst,the low-temperature region gradually moves toward the center of the catalyst,which causes the distribution characteristics of the temperature and convection field in the catalyst to *** temperature difference in vertical direction of the catalyst decreases gradually and increases in the horizontal direction,while the catalyst convection velocity has the same variation regularity in the corresponding *** variation of temperature difference and convection velocity lead the crystal growth rate in different crystal orientations to change,which directly affects the crystal morphology of the synthetic *** simulation results are consistent with the experimental results,which shows the correctness of the theoretical rational *** work is expected to be able to facilitate the understanding of catalyst structure regulation mechanism on diamond morphology and the providing of an important theoretical basis for the controllable growth of special crystal shape diamond under HPHT process.

关键词： diamond single crystal growth high pressure and high temperature crystal morphology

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crystals of suspended marine barite in the eastern equatorial Pacific:processes of dissolution and effects on crystal morphology

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Chinese Journal of Oceanology and Limnology 2015年第1期33卷 194-203页

作者：孙晓霞杨作升范德江李云海 College of Marine Geosciences Ocean University of China Key Laboratory of.Submarine Geosciences and Prospecting Technology Ministry of Education Third Institute of Oceanography State Oceanic Administration

Suspended particulate substances were sampled in the eastem equatorial Pacific in water column from surface to near bottom in five stations in 2005, from which 868 barite crystals were recovered. The barite crystals were examined under scanning electron microscopy. About 61% of the total barites crystals contained detectable Sr by energy dispersive X-ray spectrometry. Barite crystals could be classified into four groups based on their morphology： 1） bladed; 2） ovoid or rounded; 3） arrow-like; and 4） irregularly shaped. The arrow-like barite crystals in natural environment has never been reported before. In addition, about a half of the studied crystals showed features of dissolution as cavities or holes inside of the crystals or around their edges. We found that differential dissolution of barite crystals is consequence of heterogeneous Sr distribution in barite crystals. Our results would help in understanding the biogeochemical processes of marine barite formation and preservation in seawater and marine sediments.

关键词： marine barite crystal morphology Equatorial Pacific preferential dissolution Sr substitution in marine barite

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Effect of solvent on the crystal morphology of royal demolition explosive

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Journal of Beijing Institute of Technology 2015年第2期24卷 260-268页

作者：王东旭陈树森李燕月杨佳云魏田玉李丽洁 School of Materials Science and Engineering Beijing Institute of Technology Gansu Yinguang Chemical Industry Group Co Ltd

Important crystal faces that dominate the crystal morphology of royal demolition explosive （RDX） in vacuum were analyzed with the attachment energy （AE） method. Molecular dynamics （MD） simulations were used to calculate the interaction energies between these crystal faces and different solvent molecules for an attachment energy correction. Growth habits in the presence of different solvents were generated. The results showed that some crystal faces in solutions became morphologically more important than that in vacuum while others became less important. Thus, crystal shape and surface property changed a lot with the variation of crystal faces. The results from calcula- tion were in agreement with those from the re-crystallization experiment, which indicated that cyclohexanone （CH） was a promising solvent to modify the crystal morphology of RDX for obtaining products with regular shape and high purity, while butyrolactone （BL） played a great role in improving the surface electrostatic property of RDX.

关键词： royal demolition explosive (RDX) crystal morphology solvent molecular dynamics attachment energy

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Effects of Solvent and Impurities on crystal morphology of Zinc Lactate Trihydrate

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Chinese Journal of Chemical Engineering 2014年第2期22卷 221-226页

作者：杨芗钰钱刚张相洋段学志周兴贵 State Key Laboratory of Chemical Engineering East China University of Science and Technology

The crystal morphology of zinc lactate trihydrate in the absence or presence of impurities(*** acid,L-malic acid and D-malic acid)is investigated by molecular simulation based on surface docking model and COMPASS force *** simulation results with our previous experimental results,it is found that the solvent mainly has an inhibition effect on the(0 0 2)surface,and succinic acid impurity will inhibit the growth of(0 0 2)and(0 1 1)surfaces while two enantiomers of malic acid impurity will inhibit the(0 0 2)and(1 0 0)surfaces,which are in good agreement with the experimental results.

关键词： crystal morphology molecular simulation solvent effect impurity adsorption

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morphology prediction of dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) crystal in different solvent systems using modified attachment energy model

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Chinese Journal of Chemical Engineering 2023年第1期53卷 181-193页

作者： Fang Chen Tao Zhou Lijie Li Chongwei An Jun Li Duanlin Cao Jianlong Wang School of Chemical Engineering and Technology North University of ChinaTaiyuan 030051China School of Material Science and Engineering Beijing Institute of TechnologyBeijing 100081China School of Environmental and Safety Engineering North University of ChinaTaiyuan 030051China

In order to theoretically study the growth morphology of dihydroxylammonium 5,5’-bistetrazole-1,1’-dio late(TKX-50)crystal in different solvent systems,crystal–solvent models were established,and then molecular dynamics(MD)methods were adopted as a means to simulate particle *** attachment energy(MAE)model was employed to calculate the growth morphology of *** simulation results demonstrate that COMPASS force field and RESP charge are suitable for molecular dynamics simulation of *** morphologically dominant growth surfaces of TKX-50 in vacuum are(020),(011),(11–1),(100)and(120),*** water(H_(2)O)and N,N-dimethylformamide(DMF)solvents,the(11–1)face is the largest in the habit face,the growth rate of(020)face becomes *** the increase of temperature,the aspect ratios of TKX-50 crystal in DMF solvent increase,and the areas of the(120)faces *** ethylene glycol/H_(2)O mixed solvent system with volume ratio of 1/1,aspect ratio of TKX-50 is relatively *** formic acid/H_(2)O mixed solvents with different volume ratios(1/4,1/3,1/2,1/1 and 2/1),aspect ratio of TKX-50 is relatively small when volume ratio is 1/2.

关键词： TKX-50 crystal morphology Solvents Modified attachment energy model Molecular dynamics simulation

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A comparison of the proto-dolomite induced by cyanobacteria and halophilic bacteria:implications for dolomite-inducing microbe identification

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Journal of Palaeogeography 2025年第01期14卷 277-290页

作者：赵延洋 Xiang-Yu Wei Xiao Gao Na Guo Jie Li Kai-Ming Hu Chao Han Qi-Yu Wang 韩作振 Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Science and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Key Laboratory of Sedimentary Basin and Oil and Gas Resources Ministry of Natural Resources Key Laboratory of Deep Oil and Gas China University of Petroleum

This study investigates the morphological and mineralogical characteristics of proto-dolomite induced by two specific microorganisms with varying lifestyles:the extremely halophilic bacterium Vibrio harveyi QPL2 and the cyanobacterium Leptolyngbya boryana. Halophilic bacterially-induced proto-dolomite(HBD) and cyanobacterially-induced proto-dolomite (CBD) were subjected to comprehensive characterization techniques, including X-ray diffraction, scanning electron microscopy, Focused Ion Beam, thermogravimetric analysis, and X-ray photoelectron spectroscopy. The results indicate that both HBD and CBD exhibit a low degree of crystallinity and possess comparable molar ratios of MgCO3to CaCO3. Moreover, neither of them exhibits the ordered structure of ideal dolomite. HBD and CBD exhibit notable distinctions in external morphology and internal structure. HBD forms a subunit aggregate with a less dense surface and numerous pinhole structures resulting from bacterial survival. In contrast, CBD adopts a bispherical shape with a relatively dense surface and minimal indications of cyanobacterial survival. Both HBD and CBD have an internal hollow structure. However, HBD is characterized by sparse population and loosely arranged subunits, while CBD features only a central cavity. Additionally, HBD particles are smaller compared to CBD particles. These morphological differences suggest that HBD primarily grows through bacterial surface-dependent processes,whereas the growth of CBD is not directly reliant on the surface of cyanobacteria. Compositionally, the weightpercentage of crystalline water in CBD exceeded that of HBD with a value of 29.42%compared to 5.9%. This increase in internal crystalline water enables a faster conversion of CBD to the ordered ideal dolomite in a specific diagenetic environment. This study implies that the morphology and composition of microbial protodolomite may aid in identifying the type of dolomite-inducing microbes.

关键词： Proto-dolomite Cyanobacteria Halophile crystal morphology Water of crystallization

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morphology OF(Mn,Fe)S SINGLE crystal GROWTH IN CAST STEEL

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Acta Metallurgica Sinica(English Letters) 1989年第1期2卷 77-80页

作者： JIANG Xishan GONG Yansheng ZHANG Guichang Research Institute of Qiqihar Steel Works.Qiqihar,Heilongjiang,China

The step pattern of single crystal growth and the morphology at equilibrium state of(Mn, Fe)S on the wall of micro-voids in ZG25 cast steel have been observed using scanning electron *** face-centred cubic(Mn,Fe)S single crystal at equilibrium state is shown to be tetrakaidecahedron consisted of eight{111}planes and six{100}planes,and is a typical example of the O_h—m3m cubic crystal system.

关键词： cast steel (Mn,Fe)S single crystal growth crystal morphology

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The characteristic morphology of benzophenone crystal

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Progress in Natural Science:Materials International 1996年第2期 109-116页

作者：仓怀兴黄卫东周尧和

The theoretical and experimental studies on the characteristic morphology of benzophenone (BP) crystal were carried out. The experimental morphology of BP crystal was enclosed by (110), (101), (111), (Oil), (021), (010) and (001) faces of which (021), (010) and (001) faces were not predicted by the morphological theory of crystal growth. This difference was due to the neglect of the waveness of face net. The studies show that BP crystal grown from its undercooled melt could reflect its characteristic morphology.

关键词： benzophenone crystal growth crystal morphology organic crystal.

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