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Environmental Parameters of Broiler House with Three overlap Cages in Winter and Autumn 被引量:3
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作者 Shen Liyan Sa Renna +3 位作者 Niu Jinguo Liu Wenge Li Huilong Yang Wenchao 《Animal Husbandry and Feed Science》 CAS 2017年第5期275-278,333,共5页
[Objective]The study was to monitor the indoor environmental parameters of broiler house with three-overlap cages and analyze the differences in winter and autumn. [Method] In the process of feeding,the same broiler h... [Objective]The study was to monitor the indoor environmental parameters of broiler house with three-overlap cages and analyze the differences in winter and autumn. [Method] In the process of feeding,the same broiler house in the same farm was chosen to determine indoor ambient temperature,humidity and air quality at 3-6 weeks age of broilers in different seasons. The measure points were distributed in four different positions in the house. [Result] There was no significant difference in ambient temperature between autumn and winter( P > 0. 05). The ambient temperature in the house in winter was slightly higher than that in autumn. The humidity in autumn was significantly higher than that in winter( P < 0. 05). The temperature and humidity in two seasons could meet the requirements of broiler growth. There was no significant difference( P > 0. 05) in ammonia concentration between autumn and winter,while ammonia concentration in winter was slightly higher than that in autumn. The carbon dioxide concentration of broiler house in winter was significantly higher than that in autumn( P < 0. 05).The total number of airborne bacteria in winter was significantly higher than that in autumn( P < 0. 05). [Conclusion]The indoor temperature kept constant in autumn and winter seasons in closed poultry house. In winter,the humidity was reduced,the carbon dioxide concentration was increased,and the total number of bacteria in the air was increased. The ventilation in winter should be increased in case of heat preservation. 展开更多
关键词 ENVIRONMENTAL parameters WINTER and AUTUMN OVERLAP cages BROILER house
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The Surface Reactivity and Electronic Properties of Small Hydrogenation Fullerene Cages 被引量:1
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作者 A. A. El-Barbary 《Journal of Surface Engineered Materials and Advanced Technology》 2015年第3期162-168,共7页
Density functional theory calculations within the G03W package, with B3LYP exchange functional and applying basis set 6 - 31 G (d,p) are performed. The surface reactivity and electronic properties of endo-hydrogenatio... Density functional theory calculations within the G03W package, with B3LYP exchange functional and applying basis set 6 - 31 G (d,p) are performed. The surface reactivity and electronic properties of endo-hydrogenation and exo-hydrogenation fullerene cages are studied. It is found that the surface reactivity of mono-hydrogenation fullerene cages is larger than the surface reactivity of un-hydrogenation fullerene cages and the later is larger than the fully hydrogenation fullerene cages. In addition, the calculations show that the endo-hydrogenation fullerene cages possess the same band gaps as the un-hydrogenation fullerene cages, however, the exo-hydrogenation is reduced the band gaps of the un-hydrogenated fullerene cages form ~7 eV to ~5 eV. 展开更多
关键词 Surface REACTIVITY Band GAPS Small FULLERENE cages HYDROGENATION
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Dynamic Stability Analysis of Cages in High-Speed Oil-Lubricated Angular Contact Ball Bearings 被引量:12
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作者 刘秀海 邓四二 滕弘飞 《Transactions of Tianjin University》 EI CAS 2011年第1期20-27,共8页
To investigate the cage stability of high-speed oil-lubricated angular contact ball bearings, a dynamic model of cages is developed on the basis of Gupta’s and Meeks’ work. The model can simulate the cage motion und... To investigate the cage stability of high-speed oil-lubricated angular contact ball bearings, a dynamic model of cages is developed on the basis of Gupta’s and Meeks’ work. The model can simulate the cage motion under oil lubrication with all six degrees of freedom. Particularly, the model introduces oil-film damping and hysteresis damping, and deals with the collision contact as imperfect elastic contact. In addition, the effects of inner ring rotational speed, the ratio of pocket clearance to guiding clearance and applied load on the cage stability are investigated by simulating the cage motion with the model. The results can provide a theoretical basis for the design of ball bearing parameters. 展开更多
关键词 dynamic analysis high-speed angular contact ball bearing CAGE STABILITY SIMULATION
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Experimental characterization of guest molecular occupancy in clathrate hydrate cages: A review 被引量:5
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作者 Changhong Yu Litao Chen Baojiang Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第9期2189-2206,共18页
Study on the microscopic structure of clathrate hydrate has made significant progress in the past decades.This review aims to summarize the state of the art of the experimental characterization of guest molecular occu... Study on the microscopic structure of clathrate hydrate has made significant progress in the past decades.This review aims to summarize the state of the art of the experimental characterization of guest molecular occupancy in clathrate hydrate cages,which is an important area of the microscopic structures.The characterizing method and features of different guest molecular,such as hydrocarbon,carbon dioxide,hydrogen and inhibitor/promoter,in different hydrate cages have been extensively reviewed.A comprehensive use of advanced technologies such as X-ray diffraction,Raman spectroscopy and nuclear magnetic resonance may provide better understanding on the compositions and microscopic mechanisms of clathrate hydrate. 展开更多
关键词 CLATHRATE HYDRATE Cage OCCUPANCY Experimental characterization PXRD Raman NMR
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Applicability of Perinereis aibuhitensis Grube for Fish Waste Removal from Fish Cages in Sanggou Bay,P.R.China 被引量:2
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作者 FANG Jinghui JIANG Zengjie +5 位作者 JANSEN Henrice M. HU Fawen FANG Jianguang LIU Yi GAO Yaping DU Meirong 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第2期294-304,共11页
The present study investigated the applicability of integrated polychaete-fish culture for fish waste removal to offset negative impact induced by organic benthic enrichment.A field study demonstrated that deposition ... The present study investigated the applicability of integrated polychaete-fish culture for fish waste removal to offset negative impact induced by organic benthic enrichment.A field study demonstrated that deposition rate was significantly higher underneath the fish farm than that in control area.The material settling under the farm was characterized by a high amount of fish feces(45%) and uneaten feed(27%).Both feeding rate(FR) and apparent digestibility rate(ADR) increased with decreasing body weight,as was indicated by significantly a higher rate observed for the groups containing smaller individuals in a lab study.The nutrient in fresh deposited material(De) was higher than that in sediments collected under the farm(Se),resulting in lower feces production but higher apparent digestibility rate for the De group as feeding rate was similar.Consequently,higher nutrient removal efficiency was observed in the De group.A mass balance approach indicated that approximately 400–500 individuals m^(-2) is required for removing all waste materials deposited underneath the fish farm,whereas abundance can be lower(about 300–350 individuals m^(-2)) when only the fish waste needs to be removed.The results showed that a significant amount of waste had been accumulated in the fish cages in Sanggou Bay.The integration of fish with P.aibuhitensis seems promising for preventing organic pollution in the sediment and therefore is an effective strategy for mitigating negative effect of fish farms.Thus such integration can become a new IMTA(integrated multi-trophic aquaculture) model in Sanggou Bay. 展开更多
关键词 POLYCHAETE FISH CAGE FARMING IMTA carbon nitrogen environmental recovery
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Direct Z-scheme photochemical hybrid systems:Loading porphyrin-based metal-organic cages on graphitic-C_(3)N_(4) to dramatically enhance photocatalytic hydrogen evolution 被引量:5
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作者 Yang Lei Jian-Feng Huang +3 位作者 Xin-Ao Li Chu-Ying Lv Chao-Ping Hou Jun-Min Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期2249-2258,共10页
The rational design of photochemical molecular device(PMD)and its hybrid system has great potential in improving the activity of photocatalytic hydrogen production.A series of Pd6L3 type metal-organic cages,denoted as... The rational design of photochemical molecular device(PMD)and its hybrid system has great potential in improving the activity of photocatalytic hydrogen production.A series of Pd6L3 type metal-organic cages,denoted as MOC-Py-M(M=H,Cu,and Zn),are designed for PMDs by combining metalloporphyrin-based ligands with catalytically active Pd^(2+)centers.These metal-organic cages(MOCs)are first successfully hybridized with graphitic carbon nitride(g-C_(3)N_(4))to form direct Z-scheme heterogeneous MOC-Py-M/g-C_(3)N_(4)(M=H,Cu,and Zn)photocatalysts via π-πinteractions.Benefiting from its better light absorption ability,the MOC-Py-Zn/g-C_(3)N_(4) catalyst exhibits high H_(2) production activity under visible light(10348μmol g^(-1) h^(-1)),far superior to MOC-Py-H/g-C_(3)N_(4) and MOC-Py-Cu/g-C_(3)N_(4).Moreover,the MOC-Py-Zn/g-C_(3)N_(4) system obtains an enhanced turn over number(TON)value of 32616 within 100 h,outperforming the homogenous MOC-Py-Zn(TON of 507 within 100 h),which is one of the highest photochemical hybrid systems based on MOC for visible-light-driven hydrogen generation.This confirms the direct Z-scheme heterostructure can promote effective charge transfer,expand the visible light absorption region,and protect the cages from decomposition in MOC-Py-Zn/g-C_(3)N_(4).This work presents a creative example that direct Z-scheme PMD-based systems for effective and persistent hydrogen generation from water under visible light are obtained by heterogenization approach using homogeneous porphyrin-based MOCs and g-C_(3)N_(4) semiconductors. 展开更多
关键词 Porphyrin-based metal-organic cage g-C_(3)N_(4) Photochemical molecular device Direct Z-scheme heterostructure Photocatalytic hydrogen evolution from water
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Comparative Study of Two Approaches to Model the Offshore Fish Cages 被引量:6
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作者 赵云鹏 王欣欣 +3 位作者 Jud DECEW Igor TSUKROV 白晓东 毕春伟 《China Ocean Engineering》 SCIE EI CSCD 2015年第3期459-472,共14页
The goal of this paper is to provide a comparative analysis of two commonly used approaches to discretize offshore fish cages: the lumped-mass approach and the finite element technique. Two case studies are chosen to... The goal of this paper is to provide a comparative analysis of two commonly used approaches to discretize offshore fish cages: the lumped-mass approach and the finite element technique. Two case studies are chosen to compare predictions of the LMA(lumped-mass approach) and FEA(finite element analysis) based numerical modeling techniques. In both case studies, we consider several loading conditions consisting of different uniform currents and monochromatic waves. We investigate motion of the cage, its deformation, and the resultant tension in the mooring lines. Both model predictions are sufficient close to the experimental data, but for the first experiment, the DUT-Flex Sim predictions are slightly more accurate than the ones provided by Aqua-FETM. According to the comparisons, both models can be successfully utilized to the design and analysis of the offshore fish cages provided that an appropriate safety factor is chosen. 展开更多
关键词 hydrodynamics net cage lumped-mass approach truss and consistent net element
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Four Levels Anterior Cervical Discectomy and Fusion by Stand Alone PEEK Cages 被引量:1
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作者 Islam Alaghory Hany Abdel Gawwad Soliman Saeed Mostafa Abdelhameed 《Open Journal of Modern Neurosurgery》 2018年第2期162-173,共12页
Background: cervical spondylotic myelopathy is a common health problem that neurosurgeons face in Egypt. The aim of this study is to evaluate the efficacy of PEEK cage only in 4 levels anterior cervical discectomy as ... Background: cervical spondylotic myelopathy is a common health problem that neurosurgeons face in Egypt. The aim of this study is to evaluate the efficacy of PEEK cage only in 4 levels anterior cervical discectomy as one of surgical option other than anterior cervical corpectomy, fixation by plat or posterior approach for cervical laminectomy, and assessment of post spinal surgery pain. Methods: this prospective study on 28 patients with cervical spondylotic myelopathy (CSM) over a period of 3 years (between April 2012 and April 2015) with mean period of follow up 30 months. We have done anterior cervical discectomy with fixation by cage only for all cases with perioperative assessment and scoring clinically and radiologically (Japanese Orthopaedic Association [JOA] scores, Visual Analogue Scale [VAS] scores for assessment of neck and arm pain, perioperative parameters (hospital stay, blood loss, operative time), the European Myelopathy Scoring (EMS) and Odom’s criteria, and the incidence of complication,post spinal surgery pain assessment). Results: clinical outcome was excellent (28.55), good (50%) and fair (21.5) according to Odom criteria. The European Myelopathy Scoring (EMS), improved from 10 to 16. The mean JOA score improved from 10.1 ± 2.1 to 14.2 ± 2.3. Fusion failure had been seen in 4 patients in one level for each secondary to anterior displacement of the cage with no other major complications. Conclusion: 4 levels anterior cervical discectomy with PEEK cage only is an effective, save and less costly with less post operative complication and hospital stay and less post spinal surgery pain. 展开更多
关键词 Four Levels CERVICAL Disc PEEK CAGE Fusion CERVICAL Spondylotic MYELOPATHY
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Synthesis of Silsesquioxane Cages from Phenyl-cis-tetrol, 1,3-Divinyltetraethoxydisiloxane and Cyclopentyl Resins
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作者 Alan R. Bassindale Peter G. Taylor 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第4期433-436,共4页
The synthesis of T_8, T_ 10 and T_ 12 silsesquioxane cages from a range of starting materials: phenyl-cis-tetrol, 1,3-divinyltetraethoxydisiloxane and cyclopentyl T resins by using tetra n-butylammonium fluoride(TBA... The synthesis of T_8, T_ 10 and T_ 12 silsesquioxane cages from a range of starting materials: phenyl-cis-tetrol, 1,3-divinyltetraethoxydisiloxane and cyclopentyl T resins by using tetra n-butylammonium fluoride(TBAF) as the catalyst is described in this paper. The reaction yields obtained viathe current route are better compared to those viathe literature routes. Some of the cage compounds have been characterized by X-ray crystallography. 展开更多
关键词 Synthesis Silsesquioxane cage Phenyl-cis-tetrol 1 3-Divinyltetraethoxydisiloxane Cyclopentyl T resin
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Determine the Optimal Density of Nile Tilapia (<i>Oreochromis niloticus</i>) Fingerlings Cultured in Floating Cages
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作者 B. A. El Nouman O. A. Egbal +3 位作者 Y. A. Sana M. S. Anwar A. A. Eman F. A. Yosif 《Natural Resources》 2021年第1期1-9,共9页
The objective of the study was to determine the optimal density of fingerlings of the Nile tilapia (<em>Oreochromis niloticus</em>) culture in floating cages with respect to growth performance and to know ... The objective of the study was to determine the optimal density of fingerlings of the Nile tilapia (<em>Oreochromis niloticus</em>) culture in floating cages with respect to growth performance and to know the effect of temperature on growth during the winter period. Tilapia fingerlings (mean weight 8.5 ± 0.36 g) were stocked at densities of 120, 180 and 360 fish/m<sup>3</sup> for 10 weeks. During culture, fish were fed a diet contains 35% protein made of peanut seed, cottonseed, wheat bran, and Sorghum. The results showed that the increase in fish density reduced the final weight of the fish. The percentage of the fish weight increased and reached 111% ± 1.45% in the lowest fish density (120 fish/m<sup>3</sup>), 79% ± 1.87% in the medium density (240 fish/m<sup>3</sup>), and 63% ± 2.03% of high fish density (360 fish/m<sup>3</sup>), therefore the daily growth rate was better in the lowest density. The rate of food conversion ratio was also better in the lowest density with 2.17 ± 0.33, followed by the medium density with 2.79 ± 0.28 and then the highest density with 3.09 ± 0.21. However, the total production in the cage increased with increasing fish density, and the return to the cost of food was better with higher fish density. According to various performance evaluation criteria, it can be concluded that the medium density 240 fish/m<sup>3</sup> is the best for growing Nile tilapia fingerlings in floating cages. It was observed that the growth rates of the three treatments were low due to the decrease in water temperature in most of the study period, which may indicate the useless of culture in cages in the winter season. 展开更多
关键词 Cage Culture Stocking Density Nile Tilapia Fingerlings Growth Performance SUDAN
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A Balance Between Court Security and Fair Trials:Court Cages in Criminal Cases——Using European Court of Human Rights Cases for Reference
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作者 李崇涛 《The Journal of Human Rights》 2019年第2期220-240,共21页
In response to the 'cages in courts' issue in criminal trials,after reviewing a series of cases such as 'Svinarenko and Slyadnev v.Russia',the European Court of Human Rights has gradually clarified tha... In response to the 'cages in courts' issue in criminal trials,after reviewing a series of cases such as 'Svinarenko and Slyadnev v.Russia',the European Court of Human Rights has gradually clarified that the 'human dignity of the accused and his right to a fair trial are higher than the value of court security',thus found that putting the accused in a cage dock or improper use of a glass cabin dock are in breach of Article 3 and Article 6 of the European Convention on Human Rights,constitutes degrading treatment and violates the right to a fair trial.This position is in line with the international overall trend,which is of significance as a reference for China’s courts.Domestic courts should take the initiative to change the current use of the 'low fence dock' to further enhance China’s judicial civilization. 展开更多
关键词 CAGE in the COURT low FENCE DOCK COURT SECURITY right to a fair trial
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Highly Stable sp^(2) Carbon-Conjugated Porous Organic Cages 被引量:2
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作者 Fenglei Qiu Xun Chen +2 位作者 Wenjing Wang Kongzhao Su Daqiang Yuan 《CCS Chemistry》 CSCD 2024年第1期149-156,共8页
The high-yield synthesis of ultrastable porous organic cages(POCs)by facile methods is highly desirable but challenging.Inspired by highly stable sp^(2) carbon-conjugated(C=C)covalent organic frameworks,we used ration... The high-yield synthesis of ultrastable porous organic cages(POCs)by facile methods is highly desirable but challenging.Inspired by highly stable sp^(2) carbon-conjugated(C=C)covalent organic frameworks,we used rational design and synthesized the first family of sp^(2) carbon-linked POCs(sp^(2)c-POCs)with triangular prism shapes by a one-step Knoevenagel reaction that is a high yield[2+3]condensation reaction.The stability of sp^(2)c-POC was demonstrated under strenuous conditions involving for example concentrated HCl or saturated NaOH solution.sp^(2)c-POC was used as a robust adsorbent for efficient separation of CO_(2)/CH_(4) or CO_(2)/N_(2) mixtures.In view of their facile synthesis and unique properties,we expect widespread use of these sp^(2) C=C linkages in the development of POC materials. 展开更多
关键词 porous organic cages Knoevenagel condensation sp^(2)C=C linkage exceptional chemical stability gas adsorption and separation properties
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Illuminating spin-crossover octanuclear metal-organic cages 被引量:1
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作者 Zhi-Kun Liu Alyona A.Starikova +4 位作者 Yu-Xia Li Ke Sun Meng Yu Zi-Shuo Yao Jun Tao 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第4期1208-1215,共8页
Spin-crossover(SCO)materials that reversibly switch between high-and low-spin states have potential for the storage of spin state-relative information,and have gained much attention incorporating secondary physical pr... Spin-crossover(SCO)materials that reversibly switch between high-and low-spin states have potential for the storage of spin state-relative information,and have gained much attention incorporating secondary physical properties,such as fluorescence and magneto-optical switching.In this study,we synthesized three octanuclear metal-organic cages(MOCs)using tetraphenylethylene-based luminophores,aldehydes,and Fe^(Ⅱ)salts,by subcomponent self-assembly approach,namely[Fe1]-[Fe3].By controlling the ligand-field strength and guest encapsulation,we finely tuned their SCO properties.Among them,MOC[Fe2]displayed nearly complete SCO behavior in the solid state,which is rare for high-nuclearity complexes.We also demonstrated the coupling of SCO with fluorescence emission in these MOCs by using isostructural Zn^(Ⅱ)complexes([Zn1]-[Zn3])as control experiments,for the first time.Theoretical calculations revealed the energy-transfer mechanism between fluorophores and SCOactive centers,which emphasizes the significant contribution of d-d transitions in the interplay between the occurrence of SCO and fluorescence emission. 展开更多
关键词 metal-organic cages spin crossover FLUORESCENCE switching materials DFT calculation
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Recent advances in the synthesis and application of N-heterocyclic carbene-based molecular cages
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作者 Qiongjie Chai Lixin Duan +2 位作者 Yanzhe Ma Tianheng Hou Tao Tu 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第5期1510-1523,共14页
N-Heterocyclic carbene(NHC)-based cages have emerged as a prominent and dynamic research area within the research field of chemistry. Leveraging the distinctive electronic and steric properties of NHC ligands, the des... N-Heterocyclic carbene(NHC)-based cages have emerged as a prominent and dynamic research area within the research field of chemistry. Leveraging the distinctive electronic and steric properties of NHC ligands, the design, synthesis, and application of these corresponding cages have garnered substantial scholarly interest. In recent years, we have witnessed the successful fabrication of diverse NHC-based cages through a range of synthetic methodologies, which hold significant potential for applications in molecular recognition and catalysis. In this review, we delve into the foundational synthetic strategies that underlie the creation of NHC-based cages, employing approaches encompassing metal–NHC chelation, coordination assembly,and covalent bonding. Additionally, we compile the diverse applications of these cages within catalytic processes and molecular recognition. Lastly, we shed light on the current limitations of synthesis and outline future trends in the development of NHCbased cages. 展开更多
关键词 N-heterocyclic carbene molecular cages supramolecular chemistry synthetic strategies APPLICATIONS
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Porous organic cages as a novel platform for second harmonic generation
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作者 Feng Shui Yunqin Zhang +8 位作者 Mao Yi Xiongli Liu Lin Li Shuo Zhang Yongshen Zheng Yongtao Yao Qiao Zhao Baiyan Li Xianhe Bu 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第11期3669-3674,共6页
Second harmonic generation(SHG) is one of the most extensively applied nonlinear optical phenomena. Compared to traditional inorganic SHG materials, organic SHG materials, including non-centrosymmetric small molecular... Second harmonic generation(SHG) is one of the most extensively applied nonlinear optical phenomena. Compared to traditional inorganic SHG materials, organic SHG materials, including non-centrosymmetric small molecular crystals and organic polymers, have been extensively explored for SHG optics due to their advantageous properties, including high light-induced damage threshold, ultrafast response speed, high polarization ratio, wide transparency range, and elevated dielectric constant. However,in organic SHG materials, most small molecular crystals often show poor thermal stability(<200 ℃) due to their low molecular weight, which is an important obstacle for practical application under high temperatures. On the other hand, the difficulty in the growth of large-size crystals as well as the disorderly array of chromospheres on polymer chains associated with organic polymers have hindered their widespread application in SHG due to the requirements of processability and homogeneity.Therefore, it is significantly necessary to develop novel organic SHG material with high thermal stability, large-size crystals,excellent processability, high homogeneity, and a well SHG effect. In the contribution, we developed herein porous organic cages(POCs) as a novel platform for SHG optics. Thanks to its inherent macromolecular composition and zero-dimensional discrete structures, POCs can not only solve the instability problem of small molecule crystals but also overcome the drawbacks in growing large-size crystals for organic polymer. The obtained two POCs with chiral asymmetric centers(CPOC-R-5 and CPOCS-7) display advantageous features for SHG optics including well SHG performance, large-size crystal(5 mm×3 mm×1 mm),high thermal stability(≥250 ℃), wide transparency window(750–2,000 nm) and high polarization ratio(up to 94.5%). This work thus develops POCs as a new platform toward the construction of organic NLO materials with the potential application in sorts of SHG optics. 展开更多
关键词 porous organic cages second harmonic generation novel SHG platform high thermal stability large-size single crystal
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Robust Giant Octahedral[6+8]Porous Organic Cages for Efficient Ethylene/Ethane Separation
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作者 Lijuan Feng Yan-Xi Tan +4 位作者 El-Sayed MEl-Sayed Fenglei Qiu Wenjing Wang Kongzhao Su Daqiang Yuan 《CCS Chemistry》 CSCD 2024年第9期2264-2274,共11页
The exploration of ethane(C_(2)H_(6))-selective porous materials for the direct production of polymer-grade ethylene(C_(2)H_(4))from a C_(2)H_(6)/C_(2)H_(4) mixture in a single energy-saving adsorption step is of utmo... The exploration of ethane(C_(2)H_(6))-selective porous materials for the direct production of polymer-grade ethylene(C_(2)H_(4))from a C_(2)H_(6)/C_(2)H_(4) mixture in a single energy-saving adsorption step is of utmost importance but remains a significant challenge.Thus,developing robust C_(2)H_(6)-selective adsorbents with high C_(2)H_(6) capacity and C_(2)H_(6)/C_(2)H_(4) selectivity is urgently needed for industrial applications.In this study,we have successfully designed and synthesized two novel calix[4]resorcinarene-based porous organic cages(POCs)named CPOC-501 and CPOC-502.The POCs were formed via a Schiff-base reaction involving face-directed[6+8]condensation between a bowlshaped tetratopic tetraformylcalix[4]resorcinarene and triangular tritopic amine synthons.Analysis using single crystal X-ray crystallography revealed that both cages possess large truncated octahedral cavities with a volume of approximately 6500Å3 and 12 accessible rhombic windows with a side length of approximately 10.5Å.Furthermore,the cages exhibited excellent chemical stability under neutral,acidic,and basic conditions and high Brunauer–Emmett–Teller specific surface areas of up to 2175 m^(2) g^(−1) after desolvation.Both POCs demonstrated superior adsorption capabilities for C_(2)H_(6) over C_(2)H_(4).Notably,CPOC-502 exhibited a C_(2)H_(6) capacity and C_(2)H_(6)/C_(2)H_(4) selectivity of 83 cm^(3) g^(−1) and 2.83,respectively,surpassing most of the best-performing C_(2)H_(6)-selective porous organic materials reported to date.Moreover,breakthrough experiments confirmed that both cages efficiently produced polymer-grade C_(2)H_(4)(>99.9%)directly from the C_(2)H_(6)/C_(2)H_(4) mixture,highlighting their outstanding recyclability. 展开更多
关键词 C_(2)H_(6)/C_(2)H_(4)separation porous organic cages resorcinarene gas adsorption and separation host-guest interactions
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Eco-Friendly Encapsulation of Metal Clusters in Porous Organic Cages for Engineerable Microenvironment and Enhanced Catalysis 被引量:1
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作者 Siyu Ren Liangxiao Tan +5 位作者 Jun-Hao Zhou Jian Sun Peng Zhang Xingzhong Cao Yun-Hong Zhang Jian-Ke Sun 《CCS Chemistry》 CSCD 2024年第9期2186-2197,共12页
Developing artificial catalysts that mimic the functionality of enzymes and adapt to the surrounding microenvironment to achieve specific activity and selectivity is a fascinating research area yet remains a great cha... Developing artificial catalysts that mimic the functionality of enzymes and adapt to the surrounding microenvironment to achieve specific activity and selectivity is a fascinating research area yet remains a great challenge.In this work,we present a meticulously designed strategy for the successful encapsulation of ultrasmall metal clusters(MCs)within an amine-type porous organic cage(POC)through electrostatic complexation,phase transfer,and alcohol reduction processes.The amine cage showcases an intriguing and customizable feature that allows for the regulation of the surrounding microenvironment of the confined MCs through a feasible postmodifi-cation approach.This functionalization of cage skeleton further facilitates precise adjustment to the surface electronic state of Pd cluster,thereby influencing the adsorption behavior of substrate.Consequently,this controlled regulation leads to modified activity and chemoselectivity in the catalytic hydrogenation of halogenated nitrobenzene.Importantly,the investigation of the correlation between the surrounding microenvironment,substrate adsorption,and catalytic performance in the POC-immobilized MCs system has not been previously reported.We anticipate that our research will provide valuable insights in this field. 展开更多
关键词 metal cluster porous organic cage ENCAPSULATION MICROENVIRONMENT CATALYSIS
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Heterobimetallic lanthanide tetrahedral cages:Synthesis,design and application for potential multimodal imaging contrast agent
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作者 Yongxiu Li Feng Guo +4 位作者 Siwei Wei Duofu Li Jun Zhang Kai Xu Dongping Li 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第2期278-285,I0002,共9页
The construction and functionalization of lanthanide-organic cages have been a research hotspot in coordination chemistry.Benefiting from the unique luminescent and magnetic properties of lanthanide ions,the potential... The construction and functionalization of lanthanide-organic cages have been a research hotspot in coordination chemistry.Benefiting from the unique luminescent and magnetic properties of lanthanide ions,the potential applications of lanthanide-organic cages in biological imaging applications are promising,but only a few corresponding explorations have been reported.He rein,we introduced a series of lanthanide tetrahedral cages,(Eu_(n)Gd_(4-n)L_(4))(sol)_8(n=0,1,2,3 and 4,where L=(4,4',4"-tris(4,4,4-trifluoro-1,3-dioxobutyl)-triphenylamine,and sol=dimethyl sulfoxide and methanol),with potential applications in biological imaging.Given the good luminescent and magnetic properties of Eu^(3+) and Gd^(3+) ions,Eu_(4)L_(4) and Gd_(4)L_(4) complexes show a high luminescence quantum yield of 29% in DMSO and large longitudinal relaxivity(r_(1)) of 11.4(mmol/L)^(-1)/s at 0.5 T in water containing 1 vol% DMSO,respectively.The heterobimetallic Eu-Gd complexes achieve a dual imaging mode by combining luminescent and magnetic centers in one cage.When the Gd:Eu ratio increases from 1:3 to 3:1,the r_(1) values increases from 5.33 to 8.64(mmoI/L)^(-1)/s,higher than that of commercial contrast agent Gd-DOTA(3.23(mmol/L)^(-1)/s).Owing to their low toxicity and good cell imaging ability toward ECA 109 cells,the selfassembled Eu-Gd heterobimetallic tetrahedral cages could be potential candidates for the multimodal imaging contrast agent. 展开更多
关键词 Lanthanide organic cage LUMINESCENCE Cell imaging Contrast agents Rare earths
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Anion-induced differential assembly and structural transformation of supramolecular coordination cages
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作者 Shao-Ping Zheng Yao-Wei Xu +7 位作者 Pei-Yang Su Chen-Hui Liu Yin-Hui Huang Yu-Lin Lu Zhang-Wen Wei Zhiwei Jiao Hai-Sen Xu Cheng-Yong Su 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期268-272,共5页
The intimate host-anion interactions will regulate thermodynamics and kinetics in the self-assembly of cationic cages mimicking biological counterparts.Herein,we report construction and transformation of three Pd(Ⅱ)-... The intimate host-anion interactions will regulate thermodynamics and kinetics in the self-assembly of cationic cages mimicking biological counterparts.Herein,we report construction and transformation of three Pd(Ⅱ)-based metal-organic cages(MOCs)depending on different anions.Stoichiometric conversions of the lantern-shaped MOC-34 into either octahedral MOC-35 or tricapped trigonal prism MOC-36 are induced by BF_(4)^(–)or NO_(3)^(–),respectively.MOC-36 is kinetically favored and can undergo quantitative conversion to the thermodynamically preferred MOC-35 upon heating,accelerated by excess BF_(4)^(–)to motivate dissociative dynamics of Pd-vertices and lower activation barrier of cage transformation.The guest encapsulation behaviors of MOC-35 and MOC-36 have also been tested.These results manifest a significance of host-anion dynamics beyond complementary anion template,shedding light on the understanding of intricate anion recognition in nature. 展开更多
关键词 Supramolecular coordination cage Dynamic host-anion interactions Structural transformation Anion receptor Guest inclusion
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Metal-organic cages containing two types of binding sites:trapping hydrocarbon gas in solution
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作者 Meng-Ying Sun Mo Xie +6 位作者 Chuang-Wei Zhou Xue-Zhi Wang Zhao-Xia Lian Zi-Ye Chen Yong-Liang Huang Xiao-Ping Zhou Dan Li 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第7期2004-2010,共7页
The design and synthesis of artificial molecular containers for the encapsulation of hydrocarbon gases to study their host-guest chemistry are highly important for potential application in gas storage,separation,and u... The design and synthesis of artificial molecular containers for the encapsulation of hydrocarbon gases to study their host-guest chemistry are highly important for potential application in gas storage,separation,and understanding of their biological functions.In this work,we report the subcomponent self-assembly of four cubic Zn_(8)L_(12)Br_(4)(HL=N-(4-R)-1-(5-methyl-1Himidazole-4-yl)methanimine)cages with good solubility in chloroform,which are capable of binding hydrocarbon gases including methane,ethane,and ethene in solution at ambient temperature.Two types of gas binding sites(one is in the cavity,and the other is at the window)are discovered in these cages,which are documented by nuclear magnetic resonance(NMR)spectra and density functional theory(DFT)calculations.Their performance of encapsulation of hydrocarbon gases can be tuned by carefully adjusting substituent groups.These metal-organic cages containing two types of binding sites provide new artificial models to mimic the structures and functions of biological systems in binding and transforming hydrocarbon gases. 展开更多
关键词 metal-organic cages hydrocarbon gas gas encapsulation binding-sites supramolecular chemistry
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