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TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes:A novel method for the solid-phase synthesis of dihydrocoumarins and coumarins 被引量:2
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作者 E Tang Wen Li +1 位作者 Zhang Yong Gao Xi Gu 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期631-634,共4页
TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes was performed using polystyrene-supported succini- midyl selenide as the selenium source. This catalytic process provides an efficient method for th... TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes was performed using polystyrene-supported succini- midyl selenide as the selenium source. This catalytic process provides an efficient method for the regioselective synthesis of dihydrocoumarins possessing a seleno-functionality, followed by traceless cleavage of selenium linker to provide dihydrocoumar- ins and coumarins in good yields and purifies. 展开更多
关键词 Lewis acid Seleno-arylation Succinimidyl selenide solid-phase synthesis Dihydrocoumarins COUMARINS
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Controllable synthesis of CuAlO_(2) via solid-phase method and its catalytic performance for methanol steam reforming to hydrogen 被引量:4
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作者 QING Shaojun SUN Xun +3 位作者 LI Xinglong WANG Lei WU Zhiwei WANG Jianguo 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第11期1641-1651,共11页
This study explores the controllable synthesis of CuAlO_(2) using copper hydroxide and pseudo-boehmite powders as raw materials via a simple solid-phase ball milling method,along with its catalytic performance investi... This study explores the controllable synthesis of CuAlO_(2) using copper hydroxide and pseudo-boehmite powders as raw materials via a simple solid-phase ball milling method,along with its catalytic performance investigation in methanol steam reforming(MSR).Various catalysts were prepared under different conditions,such as calcination temperature,calcination atmosphere,and heating rate.Characterization techniques including BET,XRD,XPS,SEM and H2-TPR were employed to analyze the samples.The results revealed significant effects of calcination temperature on the phase compositions,specific surface area,reduction performance,and surface properties of the CA-T catalysts.Based on the findings,a synthesis route of CuAlO_(2) via the solid-phase method was proposed,highlighting the importance of high calcination temperature,nitrogen atmosphere,and low heating rate for CuAlO_(2) formation.Catalytic evaluation data demonstrated that CuAlO_(2) could catalyze MSR without pre-reduction,with the catalytic performance of CA-T catalysts being notably influenced by calcination temperature.Among the prepared catalysts,the CA-1100 catalyst exhibited the highest catalytic activity and stability.The findings of this study might be useful for the further study of the catalytic material for sustained release catalysis,including the synthesis of catalytic materials and the regulation of sustained release catalytic performance. 展开更多
关键词 CuAlO_(2) solid-phase method methanol steam reforming sustained release catalysis calcination temperature
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Synthesis of a highly hydrophobic cyclic decapeptide by solid-phase synthesis of linear peptide and cyclization in solution 被引量:5
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作者 Chen, Jian Zhang, Bei +2 位作者 Xie, Cao Lu, Yi Wu, Wei 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期391-394,共4页
A general method was described to synthesize a highly hydrophobic cyclic peptide,cyclo[LWLWLWLWLQ]where underlines indicate D-configuration of the amino acid,by a two-step solid-phase/solution synthesis strategy.The l... A general method was described to synthesize a highly hydrophobic cyclic peptide,cyclo[LWLWLWLWLQ]where underlines indicate D-configuration of the amino acid,by a two-step solid-phase/solution synthesis strategy.The linear decapeptide was assembled by standard Boc chemistry on solid-phase and subsequently cyclized in solution with high efficiency and reproducibility. In subsequent purification by semi-preparative HPLC,50%(v/v) DMF/H_2O was employed as the solvent to overcome the difficulty of solubilization... 展开更多
关键词 Cyclic peptide Decapeptide cyclo[LWLWLWLWLQ] solid-phase synthesis CYCLIZATION PURIFICATION
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Solid-phase synthesis of Cu2MoS4 nanoparticles for degradation of methyl blue under a halogen-tungsten lamp 被引量:4
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作者 Shi-na Li Rui-xin Ma Cheng-yan Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第3期310-314,共5页
The Cu_2MoS_4 nanoparticles were prepared using a relatively simple and convenient solid-phase process, which was applied for the first time. The crystalline structure, morphology, and optical properties of Cu_2MoS_4 ... The Cu_2MoS_4 nanoparticles were prepared using a relatively simple and convenient solid-phase process, which was applied for the first time. The crystalline structure, morphology, and optical properties of Cu_2MoS_4 nanoparticles were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and UV-vis spectrophotometry. Cu_2MoS_4 nanoparticles having a band gap of 1.66 eV exhibits good photocatalytic activity in the degradation of methylene blue, which indicates that this simple process may be critical to facilitate the cheap production of photocatalysts. 展开更多
关键词 Cu2MoS4 NANOPARTICLES solid-phase synthesis DEGRADATION PHOTOCATALYST METHYL blue
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Scalable solid-phase synthesis of defect-rich graphene for oxygen reduction electrocatalysis 被引量:2
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作者 Chunxiao Dong Li Yang +4 位作者 Cheng Lian Xiaoling Yang Yihua Zhu Hongliang Jiang Chunzhong Li 《Green Energy & Environment》 SCIE EI CSCD 2023年第1期224-232,共9页
Defect-engineered carbon materials have been emerged as promising electrocatalysts for oxygen reduction reaction(ORR)in metal-air batteries.Developing a facile strategy for the preparation of highly active nanocarbon ... Defect-engineered carbon materials have been emerged as promising electrocatalysts for oxygen reduction reaction(ORR)in metal-air batteries.Developing a facile strategy for the preparation of highly active nanocarbon electrocatalysts remains challenging.Herein,a low-cost and simple route is developed to synthesize defective graphene by pyrolyzing the mixture of glucose and carbon nitride.Molecular dynamics simulations reveal that the graphene formation is ascribed to two-dimensional layered feature of carbon nitride,and high compatibility of carbon nitride/glucose systems.Structural measurements suggest that the graphene possesses rich edge and topological defects.The graphene catalyst exhibits higher power density than commercial Pt/C catalyst in a primary Zn-air battery.Combining experimental results and theoretical thermodynamic analysis,it is identified that graphitic nitrogen-modified topological defects at carbon framework edges are responsible for the decent ORR performance.The strategy presented in this work can be can be scaled up readily to fabricate defective carbon materials. 展开更多
关键词 Carbon materials ELECTROCATALYSIS Oxygen reduction reaction solid-phase synthesis Zn-air battery
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Solid-phase Synthesis of PNA Monomer by Ugi Four-component Condensation Reaction 被引量:2
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作者 WenHaoWANG XiaoMinZOU XinZHANG YiQiuFU PingXU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第5期585-588,共4页
Peptide nucleic acids (PNA) oligomers were synthesized in most cases by peptide synthesis from N-protected monomers. In this work a new method of obtaining PNA monomer by Ugi four-component condensation reaction was t... Peptide nucleic acids (PNA) oligomers were synthesized in most cases by peptide synthesis from N-protected monomers. In this work a new method of obtaining PNA monomer by Ugi four-component condensation reaction was tested by solid-phase synthesis. The Fmoc protected PNA monomer was build up with thymin-1-yl acetic acid, 3-methylbutyl aldehyde, Fmoc protected aminoethyl isocyanide and Gly-Wang resin. 展开更多
关键词 Peptide nucleic acids (PNA) Ugi four-component condensation reaction (U-4CR) solid-phase synthesis Isocyanide.
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Solid-phase Synthesis of Acyl-plasminogen-Streptokinase Activator Composite(APSAC) and Its Thrombolytic Properties 被引量:1
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作者 TENGLi-rong LIANGFang +4 位作者 SUNHong QINYi HONGShui-sheng CHENJia LIULan-ying 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第5期584-587,共4页
The dialysis method has been traditionally used for the conversion of native human plasminogen(Glu-Hpg) to lys-plasminogen(Lys-Hpg). Here is described a solid-phase synthesis method for the preparation of an acyl-plas... The dialysis method has been traditionally used for the conversion of native human plasminogen(Glu-Hpg) to lys-plasminogen(Lys-Hpg). Here is described a solid-phase synthesis method for the preparation of an acyl-plasminogen-streptokinase activator complex(APSAC) from Lys-Hpg, streptokinase(SK) and chemical modification (agent(4-amidinophenyl-4′-aminobenzoate hydrochloride)) with the L-lysine-Sepharose 4B Column as the carrier. The new method significantly increases the product yield and purity over the liquid-phase methods. The APSAC prepared with the new method exhibits a significant thrombolytic effect with a long half-life of about 8.8 h in rabbits. 展开更多
关键词 Acyl-plasminogen-streptokinase activator complex(APSAC) solid-phase synthesis THROMBOLYTIC
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Use of Magic Angle Spinning ~1H NMR Spectroscopy to Monitor Reactions in Solid-Phase Synthesis 被引量:1
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作者 Ai Ming YU Hua Zheng YANG(The State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071)Ping Chuan SUN +1 位作者 Zhen Pu ZHANG Ming LI(The State Key Laboratory of Functional Polymeric Materials for Adsorption and Separation,Nankai Uni 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
Proton NMR-spectra of Wang resin bound compounds were obtained using the magic angle spinning 1HNMR technique with standard equipment. It was possible to analyse the spectra to evaluate their utility in solid-phase ch... Proton NMR-spectra of Wang resin bound compounds were obtained using the magic angle spinning 1HNMR technique with standard equipment. It was possible to analyse the spectra to evaluate their utility in solid-phase chernistry. A typical example was presented, which could directly monitor solid-phase reactions 展开更多
关键词 NMR Spectroscopy to Monitor Reactions in solid-phase synthesis Use of Magic Angle Spinning DCC DCM
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Solid-Phase Enzymatic Peptide Synthesis to Produce an Antioxidant Dipeptide
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作者 Yuyao Shan Mengfan Wang +2 位作者 Wei Qi Rongxin Su Zhimin He 《Transactions of Tianjin University》 EI CAS 2019年第3期276-282,共7页
Peptide bond synthesis is favorable to the production of bioactive small peptides. However, the abuse of toxic reagents remains an issue for chemical synthesis method, whereas the low product yield and purity limit th... Peptide bond synthesis is favorable to the production of bioactive small peptides. However, the abuse of toxic reagents remains an issue for chemical synthesis method, whereas the low product yield and purity limit the widespread use of enzymatic method. In this study, a new solid-phase enzymatic peptide synthesis(SPEPS) strategy was developed to produce an antioxidant tyrosine-alanine dipeptide(Tyr-Ala) by using recombinant carboxypeptidase Y(CPY) as the catalyst. The general SPEPS procedure involves three steps. First, the N-protected acyl donor was covalently attached to solid resin. Second,the peptide bond was condensed between the acyl donor and the nucleophile under the catalysis of CPY. Finally, one-step cleavage was performed to remove the protecting group and cleave the peptides from solid resin. Upon the optimization of reaction conditions, 77.92%(±2.723%) yield of Tyr-Ala with high product purity of 90.971%(±2.695%) was obtained.In addition, the antioxidant activity of Tyr-Ala was determined by ABTS method, indicating that the synthesized Tyr-Ala obtained by SPEPS showed a superior antioxidant capability compared with commercial glutathione. 展开更多
关键词 solid-phase ENZYMATIC PEPTIDE synthesis CARBOXYPEPTIDASE Y Tyrosine-alanine Antioxidant activity
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Solid-Phase Total Synthesis of 1-β-Methylcarbapenem
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作者 Ming LEI Cheng MA Yan Guang WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第1期6-8,共3页
A 1-b-methylcarbapenem analogue 6 was synthesized on polystyrene-diethylsilane resin (PS-DES) using 2-azetidinone bearing with 2-oxazolidone chiral auxiliary as starting material.
关键词 solid-phase synthesis of b-lactam carbapenem antibiotics.
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Solid-phase Synthesis of a Novel Kind of Hydroxylated Heterocyclic Ketene Aminals
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作者 Tao PENG Chu Yi YU Zhi Tang HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第11期1451-1453,共3页
An efficient solid-phase synthesis method for novel heterocyclic ketene aminals containing a hydroxyl group has been developed. The loading of the substrate on the resin through the hydroxyl group and the protection o... An efficient solid-phase synthesis method for novel heterocyclic ketene aminals containing a hydroxyl group has been developed. The loading of the substrate on the resin through the hydroxyl group and the protection of the amine by the Schiff base were the key steps in the synthesis. 展开更多
关键词 solid-phase synthesis Schiff base hydroxylated heterocyclic ketene aminals.
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Design and Solid-Phase Synthesis of Multiple Muramyl Dipeptide (MMD)
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作者 Shuo De ZHANG Gang LIU Su Quan XIA 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第10期887-888,共2页
As a non-specific modulator of macrophage, multiplied muramyl dipeptide (MMD) is solid-phase synthesized by application of standard Fmoc chemistry strategy. Tarn's multiple antigen system (MAS) is used as our four... As a non-specific modulator of macrophage, multiplied muramyl dipeptide (MMD) is solid-phase synthesized by application of standard Fmoc chemistry strategy. Tarn's multiple antigen system (MAS) is used as our four branched-linker on Lysine. 展开更多
关键词 multiplied muramyl dipeptide multiple antigen system MACROPHAGE solid-phase synthesis
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Polymer-support Selenium-induced Electrophilic Cyclization:Solid-phase Synthesis of Flavonoids
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作者 Jian CAO E TANG +2 位作者 Xuan HUANG Lu Ling WU Xian HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第7期857-858,共2页
The Lewis acid mediated polystyrene supported selenium cyclization of chalcones and oxidative cleavage of selenium resins flavonoids in good yields and purities have been reported. induced intramolecular gave the cor... The Lewis acid mediated polystyrene supported selenium cyclization of chalcones and oxidative cleavage of selenium resins flavonoids in good yields and purities have been reported. induced intramolecular gave the corresponding 展开更多
关键词 FLAVONOIDS selenenyl bromide resin solid-phase synthesis electrophilic cyclization.
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A Rapid Solid-phase Synthesis to Soluble Oligothiophene Molecular Wires
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作者 Hong Ming ZHANG Xian Hong WANG Xiao Jiang ZHAO Ji LI Fo Song WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第4期437-440,共4页
A novel method for the preparation of oligothiophene molecular wires is described via a bi-directional solid-phase synthesis. Using an alternating sequence of bromination and Stille coupling reactions, oligomers were ... A novel method for the preparation of oligothiophene molecular wires is described via a bi-directional solid-phase synthesis. Using an alternating sequence of bromination and Stille coupling reactions, oligomers were obtained up to the heptamer in excellent yield and purity. 展开更多
关键词 solid-phase synthesis molecular wires oligothiophene.
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SOLID-PHASE SYNTHESIS OF 4,5-DISUBSTITUTED 1,2,3-TRIAZOLES
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作者 Chen Xi LI Wen Qiang HUANG Yu LU Bing Lin HE Institute of Polymer Chemistry, Nankai University, Tianjin, 300071 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期773-774,共2页
4-Aryl-5-ethoxycarbonyl-1-H-1,2,3-triazoles have been prepared by treatment of ethyl polystyrylsulfonylacetate with substituted benzaldehydes and then sodium azide.
关键词 OC IR NH KBR solid-phase synthesis OF 4 5-DISUBSTITUTED 1 2 3-TRIAZOLES Ph
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Solid-phase Synthesis of Vinyl Sulfones Using Polystyrene-supported Selenomethyl Phenyl Sulfone
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作者 ShouRiSHENG WeiZHOU XiaoLingLIU QinXIN, CaiShengSONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第5期583-584,共2页
The solid-phase preparation of vinyl sulfones via a novel polystyrene-supported selenomethyl phenyl sulfone reagent has been reported.
关键词 solid-phase organic synthesis polystyrene-supported selenomethyl phenyl sulfone vinyl sulfone.
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Solid-phase Synthesis of Diethyl Trans-1-Aklenephosphonates Using Polymer-bound α-Diethoxyphosphoryl Methyl Selenide
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作者 ShouRiSHENG XiaoLingLIU +1 位作者 WeiZHOU XianHUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期285-286,共2页
The solid-phase preparation of diethyl trans-1 -alkenephosphonates via seleno-polymer reagent has been reported.
关键词 solid-phase organic synthesis polymer-bound α-diethoxyphosphoryl methyl selenide diethyl trans-1 -alkenephosphonate.
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A SIMPLE,MANUAL SOLID-PHASE SYNTHESIS OF OLIGORIBONUCLEOTIDE
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作者 Chun Guang WANG School of Pharmacy,Beijing Medical University Beijing 100083Sidney M.HECHT Department of Chemistry,University of Virginia Charlottesville,VA22901,USA 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期179-182,共4页
A simple,manual solid-phase synthesis of RNA fragments using 2'-(p-methoxyben- zyl)nucleosides and phosphoramidite chemistry is described.
关键词 RNA A SIMPLE MANUAL solid-phase synthesis OF OLIGORIBONUCLEOTIDE
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Synthesis and opto-electrical properties of Cu2NiSnS4 nanoparticles using a facile solid-phase process at low temperature
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作者 LI Shi-na MA Rui-xin NIU Jian-wen 《Optoelectronics Letters》 EI 2020年第6期401-404,共4页
Cu_2NiSnS_4 nanoparticles were prepared for the first time using a facile solid-phase process at a temperature of 180 °C. The crystalline structure, morphology and optical properties of the Cu_2NiSnS_4 nanopartic... Cu_2NiSnS_4 nanoparticles were prepared for the first time using a facile solid-phase process at a temperature of 180 °C. The crystalline structure, morphology and optical properties of the Cu_2NiSnS_4 nanoparticles were characterized by means of X-ray diffraction(XRD), field emission scanning electron microscopy(FESEM), transmission electron microscope(TEM) and ultraviolet-visible(UV-vis) spectrophotometer. The band gap and conversion efficiency of Cu_2NiSnS_4 nanoparticles were studied at various temperature. The results showed that the Cu_2NiSnS_4 nanoparticles exhibited an optimum band gap of 1.58 e V and a conversion efficiency of 0.64% at 180 °C, indicating that it maybe be useful in low-cost thin film solar cells. 展开更多
关键词 synthesis and opto-electrical properties of Cu_2NiSnS_4 nanoparticles using a facile solid-phase process at low temperature
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Study on Component Synthesis Active Vibration Suppression Method Using Zero-placement Technique 被引量:4
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作者 张建英 刘暾 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第4期304-312,共9页
The component synthesis active vibration suppression method (CSVS) can be applied to suppress the vibration of flexible systems. By this method, several same or similar time-varying components are arranged according... The component synthesis active vibration suppression method (CSVS) can be applied to suppress the vibration of flexible systems. By this method, several same or similar time-varying components are arranged according to certain rules along the time axis. The synthesized command can suppress the arbitrary unwanted vibration harmonic while achieving the desired rigid body motion. The number of the components increases rapidly when the number of harmonic vibration is growing. In this article, the CSVS based on zero-placement technique is used to construct the synthesized command to suppress the multi-harmonics simultaneously in the discrete domain. The nature of zero-placement method is to put enough zeros to cancel system poles at necessary points. The designed synthesized command has equal time intervals between each component and which is much easier to be implemented. Using this method, the number of components increases linearly with the increasing of the number of being suppressed harmonics. For the spacecraft with flexible appendages, CSVS based on zero-placement is used to design the time optimal large angle maneuver control strategy. Simulations have verified the validity and superiority of the proposed approach. 展开更多
关键词 flexible structure vibration suppression component synthesis active vibration suppression method zero-placement technique
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