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Molecular Dynamics Simulation of Shock Response of CL-20 Co-crystals Containing Void Defects
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作者 Changlin Li Wei Yang +5 位作者 Qiang Gan Yajun Wang Lin Liang Wenbo Zhang Shuangfei Zhu Changgen Feng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期364-374,共11页
To investigate the effect of void defects on the shock response of hexanitrohexaazaisowurtzitane(CL-20)co-crystals,shock responses of CL-20 co-crystals with energetic materials ligands trinitrotoluene(TNT),1,3-dinitro... To investigate the effect of void defects on the shock response of hexanitrohexaazaisowurtzitane(CL-20)co-crystals,shock responses of CL-20 co-crystals with energetic materials ligands trinitrotoluene(TNT),1,3-dinitrobenzene(DNB),solvents ligands dimethyl carbonate(DMC) and gamma-butyrolactone(GBL)with void were simulated,using molecular dynamics method and reactive force field.It is found that the CL-20 co-crystals with void defects will form hot spots when impacted,significantly affecting the decomposition of molecules around the void.The degree of molecular fragmentation is relatively low under the reflection velocity of 2 km/s,and the main reactions are the formation of dimer and the shedding of nitro groups.The existence of voids reduces the safety of CL-20 co-crystals,which induced the sensitivity of energetic co-crystals CL-20/TNT and CL-20/DNB to increase more significantly.Detonation has occurred under the reflection velocity of 4 km/s,energetic co-crystals are easier to polymerize than solvent co-crystals,and are not obviously affected by voids.The results show that the energy of the wave decreases after sweeping over the void,which reduces the chemical reaction frequency downstream of the void and affects the detonation performance,especially the solvent co-crystals. 展开更多
关键词 CL-20 co-crystals Molecular dynamics simulation Reactive forcefield Impact response Hot spot Void defect
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One-step rapid preparation of CL-20/TNT co-crystal assembly and spheroidized coating based on droplet microfluidic technology 被引量:1
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作者 Jiahui Shi Bidong Wu +4 位作者 Jinqiang Zhou Dawei Ren Dongxu Zhang Chongwei An Jingyu Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第9期251-262,共12页
Energetic materials pose challenges in preparation and handling due to their contradictory properties of high-energy and low-sensitivity.The emergence of co-crystal explosives is a new opportunity to change this situa... Energetic materials pose challenges in preparation and handling due to their contradictory properties of high-energy and low-sensitivity.The emergence of co-crystal explosives is a new opportunity to change this situation.If the co-crystal explosive is coated into spherical particles with uniform particle size distribution,this contradiction can be further reduced.Therefore,binder-coated hexanitrohexaazaisowurtzitane/2,4,6-trinitrotoluene(CL-20/TNT)co-crystal microspheres were prepared by droplet microfluidic technology in this work.The coating effects of different binder formulations of nitrocellulose(NC)and NC/fluorine rubber(F2604)on the co-crystal spheres were studied.The scanning electron microscopy(SEM)results showed that the use of droplet microfluidic technology with the above binders can provide co-crystal microspheres with regular spherical morphology,uniform particle size distribution and good dispersion.X-ray diffraction(XRD),fourier-transform infrared(FT-IR),differential scanning calorimetry(DSC)and thermo-gravimetric(TG)methods were employed to compare the properties of the co-crystal microspheres,raw material and pure co-crystal.The formation of CL-20/TNT co-crystal in the microspheres was confirmed,and the co-crystal microspheres exhibited better thermal stability than the raw material and pure co-crystal.In addition,the mechanical sensitivity and combustion performance of the co-crystal microspheres were further studied.The results showed that the co-crystal microspheres were more insensitive than CL-20 and pure co-crystal,and displayed excellent self-sustained combustion performance and theoretical detonation performance.This study provides a new method for the fast,simple and one-step preparation of CL-20/TNT co-crystal microspheres,with binder coating,uniform particle size distribution,and excellent performance level. 展开更多
关键词 Droplet microfluidics CL-20 TNT co-crystal Spherical coating
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Pyrolysis of CL20-BTF Co-crystal via ReaxFF-lg Reactive Force Field Molecular Dynamics Simulations 被引量:1
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作者 杨镇 何远航 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第5期557-563,I0001,共8页
To obtain detailed information on the potential energy, the evolution of species, the initial reaction paths, and thermal decomposition products, we conducted simulations on pyrolysis process of CL20/BTF co-crystal us... To obtain detailed information on the potential energy, the evolution of species, the initial reaction paths, and thermal decomposition products, we conducted simulations on pyrolysis process of CL20/BTF co-crystal using the ReaxFF/lg reaction force field, with temperature set at 2000 K to 3000 K. With the analysis of evolution curves of potential energy based on exponential function, we obtain the overall characteristic time. Via a description of the total package reaction with classical Arrhenius law, we obtain the activation energy of CL20/BTF co-crystal: Ea=60.8 kcal/mol. Based on the initial path of CL20/BTF co-crystal thermal decomposition we studied, we conclude that N-NO2 bond of CL20 molecules breaks first, working as a dominant role in the initial stage of thermal decomposition under the condition of different temperatures, and that all CL20 molecules completely decompose before BTF molecular regardless of different temperatures. We also find that the main products of CL20/BTF co-crystal are NO2, NO, NO3, HNO, O2, N2, H2O, CO2, N2O, and HONO, etc., on which the temperature forms certain influence. 展开更多
关键词 ReaxFF/lg Molecular dynamics CL20/BTF co-crystal Reaction mechanism PYROLYSIS
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Preparation of reduced sensitivity co-crystals of cyclic nitramines using spray flash evaporation 被引量:8
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作者 Mrinal Ghosh AKSikder +2 位作者 Shaibal Banerjee MBTalawar NSikder 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第1期188-200,共13页
The present day weapon technology demands novel energetic materials that exhibit simultaneous high explosive yield and reduced sensitivity.This article demonstrates application of spray evaporation to prepare reduced ... The present day weapon technology demands novel energetic materials that exhibit simultaneous high explosive yield and reduced sensitivity.This article demonstrates application of spray evaporation to prepare reduced sensitive co-crystals of high performance nitramine explosives like HMX and CL-20 with a relatively less insensitive explosive 1,1-diamino-2,2-dinitroethylene or FOX-7.Stronger intermolecurar hydrogen bonding in FOX-7 is responsible for limited solubility in nost of o rganic solvents.Large solubility differences of FOX-7 with HMX and CL-20 restricts ifs co-crystallization through classical methods that yields thermodynamically favorable product.Spray flash evaporation,a kinetic crystallization method,has been therefore adopted and could successfully produce CL-20/FOX-7(2:1) and HMX/FQX-7(4:1) co-crystals.The fine powdered materials obtained were characterized by SEM,powder XRD,Raman spectro scopy,DSC-TGA etc.Multipoint Raman spectra showed consistent occurrence of spectral features indicating stoichiometric co-existence of ingredients in the crystal lattices.DSC analysis showed absence of all thermally assisted solidsolid phase transformation in the co-crystals as they were observed in pristine materials.The thermal stability calculated in terms of activation barrier fordecomposition,revealed the CL-20/FOX-7 co-crystal to be interlediately stable on comparison to their constituents while,the HMX/FOX-7 co-crystal is more stable.Compared to pure HMX and CL-20,both the co-crystals have shown higher insensitivity to impact force,suggesting them to be suitable for future generation insensitive munitions. 展开更多
关键词 CYCLIC NITRAMINE Solubility SPRAY evaporation co-crystal REDUCED sensitivity
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Structure of Co-crystals Formation from Imidazolium and Aromatic Ligands 被引量:1
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作者 赵波 张红玲 +4 位作者 唐维 袁威冠 熊芳 敬林海 秦大斌 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第3期415-421,共7页
In this study, two new co-crystals based on rigid imidazolium ligand (2,2'-((1,1’- biphenyl)-4,4'-diyl)bis(2H-imidazo[1,5-a]pyridine-4-ium) hexafluorophosphate (L)) and 4,4'- bipyridine (Bpy) and benze... In this study, two new co-crystals based on rigid imidazolium ligand (2,2'-((1,1’- biphenyl)-4,4'-diyl)bis(2H-imidazo[1,5-a]pyridine-4-ium) hexafluorophosphate (L)) and 4,4'- bipyridine (Bpy) and benzene (Ben), formulated as L(Bpy)0.5 (co-crystal 1) and L(Ben) (co-crystal 2), were obtained. Crystal data for 1: Pī space group with α = 10.921(4), b = 16.998(6), c = 17.666(6) A, α = 95.720(7), β = 104.272(7), γ = 93.340(6)°, V = 3150.5(19) A^3 and Z = 2; and crystal data for 2: monoclinic C2/m space group with α = 25.90(2), b = 9.631(9), c = 6.371(6) A, β = 95.26(2)°, V = 1583(2) A3 and Z = 2. Co-crystal 1 was dependent on hydrogen bonds and π···π stacking, while only hydrogen bonds are present in 2. Two new co-crystals were characterized by IR, NMR spectra, thermogravimetric and ultraviolet absorption analyses. 展开更多
关键词 rigid imidazolium aromatic ligand non-covalent interactions co-crystal X-ray diffraction
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Non-merohedrally Twinned Crystal Structure of the Co-crystal Ethyl 6-(2-5-(Ethoxycarbonyl)-pyridin-2-yl-1,2-dihydroxyethyl)pyridine-3-carb-oxylateethyl 6-(2-5-(Ethoxycarbonyl)pyridin-2-yl-2-hydroxyacetyl)pyridine-3-carboxylate(0.69/0.31) 被引量:1
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作者 ZHANG Wen-Hua NG Seik Weng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第8期1159-1162,共4页
The two component molecules of the co-crystal 0.69(C18H2ON206).0.31(C18H18N2O6) lie on a center-of-inversion that exists midway along the ethylene chain connecting the two aromatic rings. The two molecules are sup... The two component molecules of the co-crystal 0.69(C18H2ON206).0.31(C18H18N2O6) lie on a center-of-inversion that exists midway along the ethylene chain connecting the two aromatic rings. The two molecules are superimposed. The crystal is also a non-morohedral twin with a minor 37.7(2)% component. The refinement of this twinned and disordered crystal structure is detailed. Crystal data: C18H19.38N2O6, monoclinic, P21/c, a = 17.1687(8), b = 5.4389(2), c = 9.3261(4) A, b = 95.270(5)° and V= 867.18(6) A3 at -173 ℃. 展开更多
关键词 co-crystal non-merohedral twin
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Synthesis,Crystal Structure and Evaluations of Its Cytotoxicity,Anti-microbial and Anti-hydroxyl Radical Activities of a New Co-crystal Compound(C6H6Cl2N2O2S)·(Phen)·H2O
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作者 黄岚珍 王雅楠 +1 位作者 蔡卓 秦秀英 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第7期1078-1086,共9页
Co-crystal is a very potential kind of drug solid forms, and has a far-reaching influence on designing and preparing drugs. A new 1:1:1 co-crystal compound consisting of 4-amino-3,5-dichloro-benzenesulfonamide, 1,10... Co-crystal is a very potential kind of drug solid forms, and has a far-reaching influence on designing and preparing drugs. A new 1:1:1 co-crystal compound consisting of 4-amino-3,5-dichloro-benzenesulfonamide, 1,10-phenanthroline and water was synthesized, and its crystal structure was characterized by X-ray diffraction method. The compositions of the co-crystal are self-assembled into a three-dimensional network structure via intermolecular interactions including hydrogen bonds, π-π stacking, Cl???Cl interactions and van der Waals' forces. According to the evaluations of cytotoxicity assays, anti-microbial and anti-hydroxyl radicals, this co-crystal is a potential drug. 展开更多
关键词 4-amino-3 5-dichloro-benzenesulfonamide co-crystal CYTOTOXICITY ANTI-MICROBIAL anti-hydroxyl radical
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Theophyllineecitric acid co-crystals easily induced by DSCeFTIR microspectroscopy or different storage conditions
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作者 Hong-Liang Lin Po-Chun Hsu Shan-Yang Lin 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2013年第1期19-27,共9页
A simultaneous differential scanning calorimetryeFourier transform infrared(DSCeFTIR)microspectroscopy was used to quickly investigate the co-crystal formulation between anhydrous theophylline(TP)and anhydrous citric ... A simultaneous differential scanning calorimetryeFourier transform infrared(DSCeFTIR)microspectroscopy was used to quickly investigate the co-crystal formulation between anhydrous theophylline(TP)and anhydrous citric acid(CA)in a one-step procedure.The raw materials of TP andCA,aswell as the intactTPeCA co-crystal prepared by slow solvent evaporation were also respectively examined by this approach.The result indicates that the TPeCA cocrystal formulation was easily induced using this DSCeFTIR technique.The thermaldependent changes in three-dimensional FTIR spectral contour profiles were started from 165C to induce the co-crystal formation of TPeCA,which was prior to the endothermic peak at 173C found in the conventional DSC curve.Beyond 165C,several new IR absorption peaks at 3515,3124,1730,1710,1677,1648,1552 and 1265 cm1 corresponding to unique IR spectral peaks of intact TPeCA co-crystal were observed.The DSCeFTIR microspectroscopic results also evidenced the dimeremonomer transition of CA,but there were no markedly changes for TP or intact TPeCA co-crystal before its fusion.This strongly implies that the DSCeFTIR technique giving spectroscopic and thermodynamic information could simultaneously induce and identify the TPeCA co-crystal formation and phase transition of samples.Different storage conditions affecting the stability of both physical mixture and ground mixture of TPeCA were also determined.The physicalmixture of TPeCA after storing at 55C/75%RH condition for one day was fast transformed to TPeCA co-crystal,indicating that TPeCA co-crystal was easily induced under accelerated storage condition.While the co-crystal formed from TPeCA ground mixture was stable in both 25C/75%RH and 55C/75%RH conditions. 展开更多
关键词 co-crystal Anhydrous theophylline Anhydrous citric acid DSCeFTIR Storage condition Ground mixture
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Synthesis, Structure and Geometrical Calculation of a Novel Co-crystal of {[4-Bromo-2-(benzimidazol-2-yl)phenolato][2-(1-butylbenzimidazol-2-yl)phenolato]zinc(Ⅱ)] and Bis[μ-2-(1-butylbenzimidazol-2-yl)phenolato]-1κN^3:2κO;1κO:2κN^3-bis{[2-(1-butylbe
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作者 TONG Yi-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第2期143-148,共6页
The title compound has been synthesized and characterized crystallographicaUy. It is a co-crystal consisting of two different neutral zinc(H) complexes with Hbpbm (Hbpbm = 4- bromo-2-(benzimidazol-2-yl)phenol) a... The title compound has been synthesized and characterized crystallographicaUy. It is a co-crystal consisting of two different neutral zinc(H) complexes with Hbpbm (Hbpbm = 4- bromo-2-(benzimidazol-2-yl)phenol) and Hnpbm (Hnpbm = 2-(1-butylbenzimidazol-2-yl)phenol). One is a monomeric mixed-ligand complex of [Zn(bpbm)(npbm)] 1 and the other a dimer of [Zn2(npbm)4] 2 with their ratio of 2:1. Thus the overall formula for the title compound is 21.2. Adjacent 1 and 2 are connected to each other by intermolecular hydrogen bonding interactions in the lattice. The crystal data: monoclinic, space group P21/c, a = 15.0141(12), b = 20.9941(17), c = 18.4686(15) A, β = 97.445(2)°, V = 5772.4(8) A^3, Mr= 2429.68, Z = 2, Dc = 1.398 g/cm^3,μ = 1.579 -1 mm , F(000) = 2504, R = 0.0637 and wR = 0.1771 for 6464 observed reflections (I 〉 2σ(I)). The geometrical structure for 1 has also been theoretically optimized and compared with the experimental one. 展开更多
关键词 zinc complex co-crystal structure 4-bromo-2-(1-butylbenzimidazol-2-yl)phenol 2-(1-butylbenzimidazol-2-yl)phenol
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One-dimensional molecular co-crystal alloys capable of full-color emission for low-loss optical waveguide and optical logic gate
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作者 Zhenhong Qi Yu-Juan Ma Dongpeng Yan 《Aggregate》 EI CAS 2024年第1期299-308,共10页
The luminescence color of molecule-based photoactive materials is the key to the applications in lighting and optical communication.Realizing continuous regulation of emission color in molecular systems is highly desi... The luminescence color of molecule-based photoactive materials is the key to the applications in lighting and optical communication.Realizing continuous regulation of emission color in molecular systems is highly desirable but still remains a challenge due to the individual emission band of purely organic molecules.Herein,a novel alloy strategy based on molecular co-crystals is reported.By adjusting the molar ratio of pyrene(Py)and fluorathene(Flu),three types of molecular co-crystal alloys(MCAs)assemblies are prepared involving Py-Flu-OFN-x%,Py-Flu-TFP-x%,Py-Flu-TCNB-x%.Multiple energy level structure and Förster resonance energy transfer(FRET)process endow materials with tunable full-spectra emission color in visible region.Impressively,these MCAs and co-crystals can be successfully applied to low optical loss waveguide and optical logic gate by virtue of all-color luminescence from blue across green to red,together with smooth surface of onedimensional microrods,which show promising applications as continuous light emitters for advance photonics applications. 展开更多
关键词 full-color emission MICRORODS molecular co-crystal optical waveguide organic alloys
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Co-crystals of non-steroidal anti-inflammatory drugs(NSAIDs):Insight toward formation,methods,and drug enhancement
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作者 Andre L.C.S.Nascimento Richard P.Fernandes +3 位作者 Maxime D.Charpentier Joop H.ter Horst Flavio J.Caires Marius Chorilli 《Particuology》 SCIE EI CAS CSCD 2021年第5期227-241,共15页
Pharmaceutical co-crystals have been explored by many researchers as a strategy to optimize physicochemical properties of solid-state drugs.Their improvements of solubility,bioavailability,and the reduced tendency for... Pharmaceutical co-crystals have been explored by many researchers as a strategy to optimize physicochemical properties of solid-state drugs.Their improvements of solubility,bioavailability,and the reduced tendency for phase transformation occurrence,are factors that highlight benefits of pharmaceutical co-crystals among other solid forms.According to the Biopharmaceutical Classification System(BCS),non-steroidal anti-inflammatory drugs(NSAIDs)are class Ⅱ drugs,which have low aqueous solubility and therefore co-crystallization has the potential to optimize NSAID product properties.In this review,we highlight the recent progress made on NSAIDs co-crystals,their co-formers,synthesis,methods and use,while we underline some promising results on in vitro and in vivo co-crystal properties.A celecoxib-tramadol co-crystal reaches phase Ⅲ clinical trials,showing greater analgesic activity than both individual APIs.The aqueous solubility of the co-crystal formed between l-proline and diclofenac is very high in comparison with the pure drug.Naproxen co-crystals with urea and thiourea have an increase of drug release of almost 60%.Co-crystal design brings a new perspective in drug development since the co-former used can also be a biologically active component allowing to combine different anti-inflammatory drugs,which have an incredible spectrum of application due to the analgesic,anti-pyretic and anti-inflammatory properties. 展开更多
关键词 Pharmaceutical co-crystals NSAIDS Supramolecular synthons co-crystal discovery BIOAVAILABILITY
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Structural Study on Four co-Crystals of N-Containing Heteroaromatics with Iodofluorobenzene 被引量:2
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作者 JI Baoming DENG Dongsheng WANG Weizhou WANG Ke HE Mengli 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2015年第1期84-90,共7页
N-Containing heteroaromatics 1,2,4,5-tetra(pyridin-3-yl)benzene[1,2,4,5-T(3-PY)B] and 1,2,4,5-tetra(pyridin-4-yl)benzene[1,2,4,5-T(4-PY)B] were each co-crystallized with 1,2-diiodo-tetrafluoro-benzene(1,2-DI... N-Containing heteroaromatics 1,2,4,5-tetra(pyridin-3-yl)benzene[1,2,4,5-T(3-PY)B] and 1,2,4,5-tetra(pyridin-4-yl)benzene[1,2,4,5-T(4-PY)B] were each co-crystallized with 1,2-diiodo-tetrafluoro-benzene(1,2-DITFB), or 1,4-diiodo-tetrafluoro-benzene(1,4-DITFB), respectively, generating four co-crystals, namely, (1,2-DITFB)4 [1,2,4,5-T(3-PY)B](1), (1,2-DITFB)4.[ 1,2,4,5-T(4-PY)B](2), (1,4-DITFB)2.[1,2,4,5-T(3-PY)B]-CHCI3(3), and (1,4-DITFB)-[1,2,4,5-T(4-PY)B]2CHCI3(4). This study takes aim at providing an insight into the relative importance of fundamental solid state halogen bonding interactions(i.e., halogen..N, halogen,..halogen, and halogen...π in systems. The effects of the donor and acceptor on supramolecular assembly and the crystal structure determined interactions were discussed. The N...I halogen bonds are the main directing interactions responsible for the observed structures. In compounds 1 and 2, the donors exhibited lower-than-expected supramolecular connectivity. In spite of this, co-crystal 2 exhibits polymeric structures consisting of infinite one-dimensional(1D) double-zigzag chains of alternating electron donor and acceptor. The basic structure of co-crystals 3 and 4 is also infinite 1D chain. Therefore, the ID halogen bonded supramolecular assemblies can be obtained by matching the appropriate donor and acceptor. 展开更多
关键词 SELF-ASSEMBLY co-crystal Halogen bond Crystal structure
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Co-crystallization of glycine anhydride with the hydroxybenzoic acids: Controlled formation of dimers via synthons cooperation and structural characterization 被引量:1
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作者 WANG Lei ZHAO Lei +3 位作者 LIU WeiMing CHEN RuiXin GU YuanXiang YANG Yu 《Science China Chemistry》 SCIE EI CAS 2012年第11期2381-2387,共7页
The results of crystallographic analyses on 1:1 and 1:4 well-defined co-crystals formed between glycine anhydride and each of 4-hydroxybenzoic acid and 3,5-dihydroxybenzoic acid are described. Neutral molecules are ... The results of crystallographic analyses on 1:1 and 1:4 well-defined co-crystals formed between glycine anhydride and each of 4-hydroxybenzoic acid and 3,5-dihydroxybenzoic acid are described. Neutral molecules are connected via heteromeric O-H.-.O and N-H…O contacts leading to different packing arrangements of supramolecular chains. On the basis of the molec- ular structures of glycine anhydride and carboxylic acid guests, the hydrogen bonds are arranged to give centrosymmetric synthons V and VII which are noteworthy for their robustness. Hydrogen-bond interactions between glycine anhydride and aromatic acid provide sufficient driving force to direct molecular recognition and crystal packing. Utilization of the orientation of functional groups of the building blocks, the acidity, and weak interactions provides a route for the creation of novel supra- molecular architectures in the crystal lattice. Both two co-crystals contain the expected hydrogen-bonded motifs, and there has been no proton transfer from either of the two carboxylic acids to the aza compound moiety. This demonstrates that glycine anhydride is very capable of affecting the construction of binary co-crystals in a predictable and rationale manner. It is noted that synthons Ⅷ and IX are fairly large, but the real challenge in crystal engineering is to find a big enough synthon that occurs often enough. Thermal stability of these compounds has been investigated by thermogravimetric analysis (TGA) of mass loss. 展开更多
关键词 co-crystalS crystal structure supramolecular synthons glycine anhydride
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Crystal Engineering of Multiple-component Organic Compound: Organic co-Crystals of the Functional Groups of Carboxyl and Amino with Persistent Hydrogen Bonding Motifs
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作者 SONG Ge BAI Feng-ying +3 位作者 XING Na CHEN Chen SHAN Hui XING Yong-heng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2013年第3期408-413,共6页
Three small organic molecular co-crystal compounds (C3N6H6)·(C6H10O4)·H2O(I), C3HsN2O(3) and (H4btec)2.(4,4'-bipy)(4)(H4btec=1,2,4,5-benzenetetracarboxylic acid, 4,4'-bipy=4,4'-bipyridine)... Three small organic molecular co-crystal compounds (C3N6H6)·(C6H10O4)·H2O(I), C3HsN2O(3) and (H4btec)2.(4,4'-bipy)(4)(H4btec=1,2,4,5-benzenetetracarboxylic acid, 4,4'-bipy=4,4'-bipyridine) and one coordination supramolecular compound [Mn(CEO4)(HEO)E]'C6HllNO2(2) were synthesized by hydrothermal reaction. They were characterized by elemental analysis, infrared(IR) spectroscopy and single crystal X-ray diffraction(XRD). Structural analyses reveal that these 2D or 3D supramolecular networks of the compounds were formed by C--H…O, N--H…O, N--H…N, O--H…O and O-H…N hydrogen bonds. Therein, the functional groups of--COOH, --NH2 and --OH play important roles in constructing supramolecular architectures. 展开更多
关键词 co-crystal compound Hydrogen bond Hydrothermal reaction
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Synthesis, Crystal Structures, Hirshfeld Surfaces, Thermo Characteristics and Solubility of Co-crystal of Buprofezin with Hydrofluoric Acid
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作者 MA Liang YAO Qing-Zhao +4 位作者 ZHOU Yu-Ming WANG Ming-Liang SUN Bai-Wang XUE Yi GUO Chang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2020年第3期500-510,378,共12页
A new kind of co-crystal of buprofezin(C(16)H(24)FN3OS) with hydrofluoric acid has been prepared through evaporation technique. It crystallizes in the triclinic space group P1, with a = 9.9733(8), b = 10.3460(9), c = ... A new kind of co-crystal of buprofezin(C(16)H(24)FN3OS) with hydrofluoric acid has been prepared through evaporation technique. It crystallizes in the triclinic space group P1, with a = 9.9733(8), b = 10.3460(9), c = 10.5739(12) ?, a = 68.655(9), b = 73.291(9), g = 66.738(8)o, V = 920.34(17) ?~3, Mr = 325.44, Dc = 1.174 g/cm^3, Z = 2, F(000) = 348, m = 0.190 mm^(-1), the final GOOF = 1.042, R = 0.0485 and wR = 0.1167. Single-crystal X-ray diffraction, XRPD, DSC, TGA, Hirshfeld surface analysis, Raman spectroscopy and FT-IR were used to characterize the co-crystal. It has a twodimensional plane structure, and the intermolecular interactions of co-crystal are mainly H–F×××H, H–O×××H and H–O×××H. Thermology study further confirmed that co-crystal has stronger thermal stability and higher melting point than buprofezin, and it has stronger water solubility. The results show that this co-crystal is valuable for the study of residual activity and application effects of buprofezin. 展开更多
关键词 co-crystal BUPROFEZIN X-RAY thermal stability
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The antioxidant and physicochemical properties of microencapsulated bioactive compounds in Securigera securidaca(L.)seed extract by co-crystallization
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作者 Ali Behnam Nik Mohsen Vazifedoost +1 位作者 Zohreh Didar Bahareh Hajirostamloo 《Food Quality and Safety》 SCIE CSCD 2019年第4期243-250,共8页
Securigera securidaca seed is a good source of phenolic compounds with high antioxidant properties.Preservation and maintenance of natural antioxidants have always been a challenge and microencapsulation is a suitable... Securigera securidaca seed is a good source of phenolic compounds with high antioxidant properties.Preservation and maintenance of natural antioxidants have always been a challenge and microencapsulation is a suitable method for this purpose.In this study,the chemical compounds of the plant seed extract were identified by GC/MS device.Bioactive compounds from the seed ethanolic extract were microencapsulated in the sucrose matrix during the co-crystallization process.The evaluations included total phenolic compounds,radical scavenging ability,production efficiency,moisture content,and flowability characteristics of the produced powders,such as compressibility index,Hausner ratio,and angle of repose.The results showed significant differences in the phenolic compounds and the radical scavenging ability between the control sample and the co-crystallized powder(P<0.05).The production efficiency and the moisture content of extract-containing co-crystallized powder were 84%and 0.14%,respectively.The particle size difference of the microencapsulated powder could significantly affect the powder flowability characteristics(P<0.05),and particles with a size of 1 mm showed better flowability behaviour.FT-IR charts for samples revealed chemical bonds specific to saccharose molecule indicating no changes in covalent bonds present in saccharose molecule structure after the process.Scanning electron microscope images showed the presence of vacant spaces and porosity in the structure of saccharose crystals formed during the process of crystallization.As a result,the co-crystallized powder obtained from the plant extract can be used as an appropriate antioxidant in the food and pharmaceutical formulations. 展开更多
关键词 co-crystalLIZATION natural antioxidant bioactive FLOWABILITY
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Pressure-induced Diels-Alder reactions in C_6H_6—C_6F_6 Co-crystal towards graphane structure
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《Science Foundation in China》 CAS 2019年第1期41-41,共1页
With support from the National Natural Science Foundation of China and the Top 1000-Talents Awards,the research team led by Dr.Zheng HaiYan(郑海燕)and Dr.Li Kuo(李阔)from the Center for High Pressure Science and Techn... With support from the National Natural Science Foundation of China and the Top 1000-Talents Awards,the research team led by Dr.Zheng HaiYan(郑海燕)and Dr.Li Kuo(李阔)from the Center for High Pressure Science and Technology Advanced Research in Beijing recently synthesized H-F-substituted graphane(H,F-graphane)with a layered structure by compressing 1:1 C6H6-C6F6 co-crystal(abbreviated as CHCF). 展开更多
关键词 PRESSURE-INDUCED DIELS-ALDER reactions C6H6--C6F6 co-crystal GRAPHANE STRUCTURE
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冲击作用下CL⁃20含能共晶的反应分子动力学模拟
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作者 伍俊英 方汇璇 +3 位作者 尚伊平 李钧剑 王健宇 陈朗 《含能材料》 EI CSCD 北大核心 2024年第1期49-64,共16页
共晶技术是降低六硝基六氮杂异伍兹烷(CL‐20)感度的有效方法之一,研究冲击作用下CL‐20共晶的化学反应,有助于理解CL‐20共晶的冲击反应机制,对炸药安全评价分析具有重要意义。本研究采用ReaxFF‐lg反应力场的分子动力学方法,同时结合... 共晶技术是降低六硝基六氮杂异伍兹烷(CL‐20)感度的有效方法之一,研究冲击作用下CL‐20共晶的化学反应,有助于理解CL‐20共晶的冲击反应机制,对炸药安全评价分析具有重要意义。本研究采用ReaxFF‐lg反应力场的分子动力学方法,同时结合非平衡加载方法,对CL‐20/2,5‐二硝基甲苯(DNT)、CL‐20/1,3‐二硝基苯(DNB)和CL‐20/1‐甲基‐3,5‐二硝基‐1,2,4‐三唑(MDNT)三种共晶在2~5 km·s^(-1)冲击速度下的冲击压缩过程进行了分子动力学模拟,获得了含能共晶在冲击作用后的热力学演化特征、初始化学反应路径和产物信息,并与CL‐20的情况进行了对比分析。研究发现:CL‐20/DNT、CL‐20/DNB和CL‐20/MDNT 3种共晶都有一定程度的降低冲击感度作用,3种共晶的冲击感度顺序依次为CL‐20/MDNT>CL‐20/DNB>CL‐20/DNT。3种共晶的分解反应均是从CL‐20分解开始,且CL‐20的分解速度比DNT、DNB和MDNT快。在2 km·s^(-1)冲击速度下,CL‐20共晶首先发生聚合反应,CL‐20与共晶配体分子间的聚合反应早于CL‐20分子间的聚合,且反应频次远高于CL‐20分子之间聚合。在3 km·s^(-1)的冲击条件下,CL‐20首先发生了N—N以及C—N键断裂,笼型结构被破坏,同时生成NO_(2),CL‐20初步断键后的结构及产物NO_(2)会进一步与共晶配体分子DNT、DNB、MDNT结合,降低CL‐20反应中间产物的浓度,达到降感作用。在4,5 km·s^(-1)冲击条件下,CL‐20中的环状骨架结构会直接遭到破坏,发生C—N键断裂,产生小分子碎片,直接生成N2,同时有NO_(2)、H_(2)、CO_(2)、H_(2)O等产物生成。 展开更多
关键词 含能共晶 反应力场 分子动力学 冲击波 反应机理
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镓硼共掺对6英寸VGF法锗单晶电阻率均匀性的影响
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作者 张颖武 边义午 +3 位作者 陈晨 周春锋 王云彪 兰天平 《半导体技术》 CAS 北大核心 2024年第8期708-712,725,共6页
由于杂质分凝效应,镓掺杂垂直梯度凝固(VGF)法锗单晶的电阻率分布不均匀,理论上利用镓和硼分凝系数的差异,镓硼共掺工艺可以提升锗单晶电阻率均匀性。采用镓硼共掺工艺制备了6英寸(1英寸≈2.54 cm)VGF法锗单晶,对比分析了掺杂工艺对锗... 由于杂质分凝效应,镓掺杂垂直梯度凝固(VGF)法锗单晶的电阻率分布不均匀,理论上利用镓和硼分凝系数的差异,镓硼共掺工艺可以提升锗单晶电阻率均匀性。采用镓硼共掺工艺制备了6英寸(1英寸≈2.54 cm)VGF法锗单晶,对比分析了掺杂工艺对锗单晶电阻率均匀性的影响。当镓和硼杂质浓度分别为5.13×10^(18)cm^(-3)和0.67×10^(18)cm^(-3)时,在等径0~40 mm范围内轴向电阻率不均匀性为4.92%,等径0 mm和40 mm处径向电阻率不均匀性分别为1.63%和0.45%,与镓杂质浓度为5.13×10^(18)cm^(-3)的镓掺杂工艺相比,锗单晶头部的电阻率均匀性明显提升。当硼杂质浓度提高到1.89×10^(18)cm^(-3)时,镓硼共掺锗单晶头部电阻率均匀性变差。结果表明,适量硼掺杂的镓硼共掺工艺可以提升锗单晶头部电阻率均匀性。 展开更多
关键词 6英寸 垂直梯度凝固(VGF)法 锗单晶 镓硼共掺 电阻率 均匀性
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五角双锥构型的场诱导Co^(Ⅱ)单离子磁体
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作者 赵淑艳 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第8期1583-1591,共9页
利用CoCl_(2)·6H_(2)O和2,6-二乙酰吡啶双(氨基脲)(H_(2)dapsc)在水和乙醇的混合溶剂中回流反应得到一例具有五角双锥构型的单核Co~Ⅱ配合物[Co(H_(2)dapsc)(H_(2)O)Cl]Cl·2H_(2)O(1),其中中性的H_(2)dapsc配体分子提供5个配... 利用CoCl_(2)·6H_(2)O和2,6-二乙酰吡啶双(氨基脲)(H_(2)dapsc)在水和乙醇的混合溶剂中回流反应得到一例具有五角双锥构型的单核Co~Ⅱ配合物[Co(H_(2)dapsc)(H_(2)O)Cl]Cl·2H_(2)O(1),其中中性的H_(2)dapsc配体分子提供5个配位原子构成其赤道平面,1个水分子和1个Cl^(-)离子则占据其轴向位置,同时在其固态结构中包含1个价态平衡Cl^(-)离子和晶格水分子。直流磁化率研究表明,该配合物具有强的磁各向异性;交流磁性质表明其存在慢磁弛豫行为,直接和拉曼过程同时主导其弛豫,自旋翻转能垒为55.55 K。结合理论计算可以得出,导致该配合物慢磁弛豫行为的主要原因是五角双锥结构的面内各向异性,计算得到的D、E值为45.68、-0.32 cm^(-1)。 展开更多
关键词 Co^(Ⅱ)配合物 五角双锥 晶体结构 磁性质
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