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Defence Technology（防务技术） 2021年第4期17卷 1387-1394页

作者： Yong-qiang Du Jian Zheng gui-bo Yu Shijiazhuang Campus Army Engineering UniversityShijiazhuang050003China

In order to predict the storage life of a certain type of HTPB(hydroyl-terminated polybutadiene)coating at 25℃ and analyze the influence of pre-strain on the storage life,the accelerated aging tests of HTPB coating at 40℃,50℃,60℃,70℃ with the pre-strain of 0%,3%,6%,9%,respectively were carried *** variation regularity of the change of crosslinking density was analyzed and the aging model of HTPB coating under pre-strained thermally-accelerated aging was *** storage life of HTPB coating at 25℃ was estimated by using the Berthelot equation as the end point of the aging life with a 30% decrease in maximum *** results showed that the change of crosslinking density of HTPB coating increased with the increase of aging temperature and aging time,and decreased with the increase of *** 0% prestrain,the relationship between the change of crosslinking density of HTPB coating and the aging time can be described by the logarithmic model with the confidence probability greater than 99%.The stress relaxation phenomenon existed under 3%,6%and 9%pre-strained *** aging model considering chemical aging and pre-strain was established with the confidence probability greater than 90%.The storage life of HTPB coating was 15.2935 years at 25C under 0% prestrain,which was reduced by 13.9007%,75.6949% and 89.7859% under 3%,6% and 9% pre-strain,*** existence of pre-strain has a serious impact on the storage life of HTPB coating,therefore,the pre-strain should be avoided as much as possible during the actual storage.

关键词： HTPB coating Crosslinking density Aging model Storage life prediction Berthelot

Tuning Energy Transfer in Metal-OrganicFrameworks for Fluorescence Turn-on Sensing of Hg(Ⅱ)Ions

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Chinese Journal of Chemistry 2023年第9期41卷 1051-1056页

作者： Xuejiao Wang Arindam Mal bo gui Cheng Wang Sauvage Center for Molecular Sciences and Hubei Key Lab on Organic and Polymeric Optoelectronic Materials College of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China

Tuning F?rster resonance energy transfer(FRET)in metal-organic frameworks for fluorescence turn on sensing is rarely ***,we designed and synthesized several FRET-based metal-organic frameworks(MOFs)with different donor/acceptor *** the oxidation of the acceptor,the FRET process in MOFs can be efficiently modulated so as to turn-on the fluorescence of the framework in a controlled ***,the MOF with an optimized donor/acceptor ratio of 7.0 was used as an efficient fluorescence turn on sensor for Hg(Ⅱ)ions with good sensitivity and *** believe our present study will not only give a useful method to construct fluorescence turn-on sensors but also trigger the construction of novel FRET-based MOFs for the fluo-rescence turn-on sensing of target analytes in the future.

关键词： Energy transfer FluorescenceHg(Ⅱ)ions Sensors Metal-organic frameworks

Spin Polarization Properties of Na Doped Meridianal Tris（8-Hydroxyquinoline） Aluminum Studied by First Principles Calculations

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Chinese Physics Letters 2014年第4期31卷 193-196页

作者： REN Jun-Feng YUAN Xiao-bo HU gui-Chao College of Physics and Electronics Shandong Normal University Jinan 250014

We theoretically investigate the electronic structure and spin polarization properties of Na-doped meridianal tris（S-hydroxyquinoline） aluminum （Alq3） by first principles calculations. It is found that the spin density is distributed mainly in the Alq3 part in the Alq3：Na complex. Electron charge transfer takes place from the Na atom to the Alq3 molecule, which induces asymmetric changing of the molecule bond lengths, thus the spin density distribution becomes asymmetric. Spin polarization of the complex originates from the preferable filling of the spin-split nitrogen and carbon p-orbitals because of the different bond length changes of the Aiq3 molecule upon Na doping.

关键词： Calculations Spin Polarization electronic

Transverse relaxation characteristic and stress relaxation model considering molecular chains of HTPB coating based on pre-strained thermal aging

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Defence Technology（防务技术） 2021年第3期17卷 821-828页

作者： Yong-qiang Du Jian Zheng gui-bo Yu Jian-zhuang Zhi Shijiazhuang Campus Army Engineering UniversityShijiazhuang050003China Intelligent Manufacturing Institute Hebei College of Industry and TechnologyShijiazhuang050003China

In order to accurately describe the transverse relaxation characteristic and stress relaxation modulus of HTPB coating during pre-strain thermal aging process,a one month thermal aging test was carried out at70C with pre-strain of 0%,3%,6%and 9%,*** low-field1 H NMR and stress relaxation modulus tests were carried out for HTPB coating at different aging *** stress relaxation model considering the molecular chains was proposed according to the changes of crosslinking chain and dangling chain of HTPB coating during pre-strain *** results showed that with the increase of aging time,the decay rate of transverse relaxation curve became faster,the transverse relaxation time decreased,the value of combined parameter q Mrl increased,the proportion of crosslinking chain decreased,while the proportion of dangling chain ***,the stress relaxation modulus increased,the crosslinking network structure of HTPB coating became denser and the degree of crosslinking *** the initial aging stage,the pre-strain will destroy the crosslinking network structure of HTPB coating to a certain *** the increase of aging time,the effect of pre-strain will gradually weaken and the influence of aging on materials will gradually *** correlations between the stress relaxation model considering the molecular chains and the test results were more than 0.9950,which can accurately describe the stress relaxation modulus of HTPB coating during the pre-strain thermal aging process.

关键词： HTPB Pre-strain aging Transverse relaxation characteristic Molecular chain Stress relaxation model

Postsynthetic Modification of Metal-Organic Frameworks through Click Chemistry

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Chinese Journal of Chemistry 2016年第2期34卷 186-190页

作者： bo gui Xiangshi Meng Hai Xu Cheng Wang Key Laboratory of Biomedical Polymers (Ministry of Education) College of Chemistry and Molecular Sciences Wuhan University Wuhan Hubei 430072 China College of Chemistry and Chemical Engineering Central South University Changsha Hunan 410083 China

The postsynthetic modification （PSM） of metal-organic frameworks （MOFs） has emerged as a powerful tool to chemically tailor the interior of MOFs. In this review, we summarize the research progress of PSM of MOFs t... 详细信息

关键词： postsynthetic modification metal-organic frameworks click chemistry azide-alkyne click reaction thiol-ene reaction

Preparation and characterization of regenerated MgO–CaO refractory bricks sintered under different atmospheres

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International Journal of Minerals,Metallurgy and Materials 2014年第12期21卷 1233-1240页

作者： gui-bo Qiu Chang-sheng Yue Xiang Li Min Guo Mei Zhang Beijing Key Lab of Green Recycling and Extraction of Metals School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Central Research Institute of Building and Construction Co. Ltd. Metallurgical Corporation of China Ltd.

Regenerated MgO-CaO brick samples containing 80wt%, 70wt%, and 60wt% MgO were prepared using spent MgO-CaO bricks and fused magnesia as raw materials and paraffin as a binder. The bricks were sintered at 1873 K for 2 h under an air atmosphere and under an isolating system. The microstructure, mechanical properties at room temperature, and hydration resistance of the regenerated samples were measured and compared. The results indicated that the isolating sintering generated a strongly reducing atmosphere as a result of the incomplete combustion of paraffin, and the partial oxygen pressure was approximately 6.68 × 10^-7 Pa. The properties of the regenerated bricks sintered under air conditions were all higher than those of the bricks sintered under a reducing atmosphere. The deterioration of the bricks was a result of MgO reduction and a decrease in the amount of liquid phase formed during sintering under a reducing atmosphere.

关键词： refractories regeneration sintering atmospheres mechanical properties hydration

Structural tailoring of covalent organic frameworks with steric effects

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Science China Chemistry 2023年第11期66卷 2977-2985页

作者： guiqing Lin Arindam Mal Xuejiao Wang Xu Zhou bo gui Cheng Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

Covalent organic frameworks(COFs)provide a unique platform with tunable structures allowing precise control of pore sizes,shapes and *** key to synthesizing COFs with desired structures is to precisely control the conformation and geometry of building blocks as well as the growth direction of *** achieve this,steric effects are noteworthy that may have a significant impact on the assembly of ***,the introduction of sterically demanding substituents or bulky groups into monomers of COFs will lead to intramolecular conformational changes and intermolecular repulsions,which induce structural changes in COFs,including changes in torsion angles,interlayer distances,stacking modes and topologies of 2D COFs,and changes in spatial nodes,interpenetration and topologies of 3D *** review will help to understand the impacts of steric effects on the structures of COFs and to take them into extensive consideration in the design and synthesis of COFs with novel functionalities and structural attributes.

关键词： covalent organic frameworks steric effect structural tailoring

Preparation and characterization of hexadecane microcapsule with polyurea-melamine formaldehyde resin shell materials

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Chinese Chemical Letters 2010年第5期21卷 533-537页

作者： Gao, gui bo Qian, Chun Xiang Gao, Min Jie Southeast Univ Sch Mat Sci & Engn Nanjing 211189 Peoples R China

This paper gives a brief report of the preparation of hexadecane microcapsule with polyurea-melamine formaldehyde resin shell materials(HMPM).The sealing performance and thermal stability of HMPM was enhanced much more effectively than that of microcapsule with polyurea shell material(HPM).The results of microscopical imaging analysis system,DSC,TG,and laser particle analyzer were briefly introduced.

关键词： Hexadecane Polyurea Melamine formaldehyde resin Microcapsule Phase change properties

Structural measurements and vessel density of spectraldomain optic coherence tomography in early,moderate,and severe primary angle-closure glaucoma

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International Journal of Ophthalmology(English edition) 2023年第7期16卷 1100-1109页

作者： Wei Jiang Nan Jiang gui-bo Liu Jing Lin Cui Li gui-Qiu Zhao Department of Ophthalmology the Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

AIM:To compare the macular ganglion cell-inner plexiform layer(GCIPL)thickness,retinal nerve fiber layer(RNFL)thickness,optic nerve head(ONH)parameters,and retinal vessel density(VD)measured by spectral-domain optical coherence tomography(SD-OCT)and analyze the correlations between them in the early,moderate,severe primary angle-closure glaucoma(PACG)and normal ***:Totally 70 PACG eyes and 20 normal eyes were recruited for this retrospective *** eyes were further separated into early,moderate,or severe PACG eyes using the Enhanced Glaucoma Staging System(GSS2).The GCIPL thickness,RNFL thickness,ONH parameters,and retinal VD were measured by SD-OCT,differences among the groups and correlations within the same group were ***:The inferior and superotemporal sectors of the GCIPL thickness,rim area of ONH,average and inferior sector of the retinal VD were significantly reduced(all P<0.05)in the early PACG eyes compared to the normal and the optic disc area,cup to disc ratio(C/D),and cup volume were significantly higher(all P<0.05);but the RNFL was not significant changes in early and moderate *** severe group,the GCIPL and RNFL thickness were obvious thinning with retinal VD were decreasing as well as C/D and cup volume increasing than other three groups(all P<0.01).In the early PACG subgroup,there were significant positive correlations between retinal VD and GCIPL thickness(except superonasal and inferonasal sectors,r=0.573 to 0.641,all P<0.05),superior sectors of RNFL thickness(r=0.055,P=0.049).More obvious significant positive correlations were existed in moderate PACG eyes between retinal VD and superior sectors of RNFL thickness(r=0.650,P=0.022),and temporal sectors of RNFL thickness(r=0.740,P=0.006).In the severe PACG eyes,neither GCIPL nor RNFL thickness was associated with retinal ***:The ONH damage and retinal VD loss appears earlier than RNFL thickness loss in PACG *** the PACG disease progressed from the earl

关键词： optic coherence tomography primary angle-closure glaucoma ganglion cell-inner plexiform layer retinal nerve fiber layer optic nerve head retinal vessel density

Topology control of three-dimensional covalent organic frameworks by adjusting steric hindrance effect

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Science China Chemistry 2022年第11期65卷 2177-2181页

作者： Yang Xie Meng Liu Honglin Du bo gui Junliang Sun Cheng Wang Sauvage Center for Molecular Sciences College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing100871China

Since the intrinsic topological network determines their pore characteristics and functional applications, it is important to construct 3D COFs with target topology from predesigned functional building blocks. However, when starting from precursors with same connectivity but different bulky groups, the structure and topology of 3D COFs may change, which will greatly increase the complexity of the crystal structure determination. Therefore, it is essential to understand how to control the steric hindrance effects and synthesize 3D COFs with target topology. Herein, we report the topology control of 3D COFs by adjusting steric hindrance effects of functional building blocks. Starting from a quadrilateral building block with sterically hindered phenyl groups, we have been able to achieve the target pts topology instead of the unprecedented ljh network that we reported recently by elongating the tetrahedral building block. This result clearly shows that it is promising to precisely control the topology of 3D COFs by judiciously selecting building blocks with steric hindrance and suitable dimensions.

关键词： COF 3D reticular chemistry topology control steric hindrance effect

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