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Development of a novel Cu(I)π-complexation adsorbent for ultra-deep desulfurization from a carbon dioxide stream
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作者 Huating Ju Yongchun Zhang +12 位作者 Jikai Zhang Ziqi Yu Yige Zhang Xiongfu Zhang Xinwen Guo Jiaxu Liu Qing Mao Qi Liu Yiming Zhao Tianqinji Qi Xiao Jiang Zhen Guo Shaoyun Chen 《Smart Molecules》 2025年第1期101-113,共13页
Desulfurization technology is rather difficult and urgently needed for carbon dioxide(CO_(2))utilization in industry.A new Cu(I)-based adsorbent was synthesized and examined for the capacity of removing carbonyl sulfi... Desulfurization technology is rather difficult and urgently needed for carbon dioxide(CO_(2))utilization in industry.A new Cu(I)-based adsorbent was synthesized and examined for the capacity of removing carbonyl sulfide(COS)from a CO_(2)stream in an effort to solve the competitive adsorption between CO_(2)and COS and to seek opportunity to advance adsorption capacity.A wide range of character-ization techniques were used to investigate the physicochemical properties of the synthesized Cu(I)adsorbent featuringπ-complexation and their correlations with the adsorption performance.Meanwhile,the first principal calculation software CP2K was used to develop an understanding of the adsorption mechanism,which can offer useful guidance for the adsorbent regeneration.The synthesized Cu(I)adsorbent,prepared by using copper citrate and citric acid on the ZSM-5(SiO_(2)/Al_(2)O_(3)=25)carrier,outperformed other adsorbents with varying formulations and carriers in adsorption capacities.Through optimization of the preparation and adsorption conditions for various adsorbents,the breakthrough adsorption capacity(Qb)for COS was further enhanced from 2.19 mg/g to 15.36 mg/g.The formed stableπ-complex bonds between COS and Cu(I),as confirmed by density func-tional theory calculations,were verified by the significant improvement in the adsorption capacity after regeneration at 600°C.The above advantages render the novel synthesized Cu(I)adsorbent a promising candidate featuring cost-effectiveness,high efficacy and good regenerability for desulfurization from a CO_(2)stream. 展开更多
关键词 π-complexed adsorption carbonyl sulfide CO_(2)purification Cu(I)adsorbent DESULFURIZATION
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Preparation of porous MgO/ZrO_(2)-supported amine-based adsorbents and their application in CO_(2)capture
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作者 SHI Guoliang ZHANG Xinying +1 位作者 LI Xiaolan HOU Chunyue 《燃料化学学报(中英文)》 北大核心 2025年第6期935-942,共8页
Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent material... Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent materials were successfully synthesized by loading TEPA onto the pore MgO/ZrO_(2)carriers in the paper.The pore structure and surface characteristic of the samples were analyzed by using XRD,BET,FT-IR and SEM.The adsorbent materials exhibited microcrystalline state,and the crystallinity of all samples gradually decreased as the increase of TEPA content.The pore structure analysis indicated that the modification of MgO-ZrO_(2)adsorbents with TEPA led to the decrease of the specific surface areas,but the narrow micro-mesopore size distributions ranging from 1.8-12 nm in the adsorbents still were maintained.FT-IR spectrum results further verified the successful loading of TEPA.The adsorption capacity of the adsorbents for CO_(2)were tested by using an adsorption apparatus equipped with gas chromatography.The results indicated that when the TEPA loading reached 50%,the sample exhibited the maximum adsorption value for CO_(2),reaching 4.07 mmol/g under the operation condition of 75℃and atmospheric pressure.This result could be assigned to not only the base active sites but also the coexistence of both micropore and mesopore in the adsorbent.After three cycles tests for CO_(2)capture,the adsorption value of the sample for CO_(2)can also reached 95%of its original adsorption capacity,which verified the excellent cyclic operation stability. 展开更多
关键词 CO_(2)capture amine-based adsorbent impregnation micro-mesopore adsorption
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PREPARATION OF UREA NITROGEN ADSORBENT OF COMPLEX TYPE AND ADSORPTION CAPACITY OF UREA NITROGEN ONTO THE ADSORBENT
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作者 梁足培 冯亚青 +1 位作者 梁智妍 孟舒献 《Transactions of Tianjin University》 EI CAS 2006年第1期37-41,共5页
The urea nitrogen adsorbent of complex type, which consists of chitosan coated dialdehyde cellulose (CDAC) and immobilized urease in gelatin membrane (IE), was prepared. The cellulose, the dialdehyde cellulose (... The urea nitrogen adsorbent of complex type, which consists of chitosan coated dialdehyde cellulose (CDAC) and immobilized urease in gelatin membrane (IE), was prepared. The cellulose, the dialdehyde cellulose (DAC) and the CDAC were characterized by scanning electronic microscope. The results indicate that the cellulose C2-C3 bond was broken under the oxidation of periodate and it was oxidated to DAC. The DAC was coated with chitosan and the CDAC was obtained. The adsorption of urea nitrogen onto the adsorbent in Na2HPO4-NaH2PO4 buffer solution was studied in batch system. The effects of the experiment parameters, including degree of oxidation of CDAC, initial urea nitrogen concentration, pH and temperature, on the adsorption capacity of urea nitrogen onto the adsorbent at CDAC/IE weight ratio 10:1 were investigated. The results indicate that these parameters affected significantly the adsorption capacity. The adsorption capacity of urea nitrogen onto the adsorbent was 36.7 mg/g at the degree of oxidation of CDAC 88%, initial urea nitrogen concentration 600 mg/L, pH 7.4 and temperature 37℃. 展开更多
关键词 adsorption urea nitrogen complex type adsorbent chitosan coated dialdehyde cellulose immobilized urease bio-catalysis
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Facile synthesis of boron-doped porous biochar as a metal-free adsorbent for efficient removal of aqueous tetracycline antibiotics
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作者 Lu Xu Yuetong Qi +5 位作者 Shaolei He Chengzhi Wang Xin Jin Qize Wang Kai Wang Pengkang Jin 《Journal of Environmental Sciences》 2025年第6期235-247,共13页
This study introduced a microwave-assisted pyrolysis method for the rapid and efficientpreparation of boron-doped porous biochar. The resulting biochar exhibited a large specificsurface area (933.39 m^(2)/g), a rich p... This study introduced a microwave-assisted pyrolysis method for the rapid and efficientpreparation of boron-doped porous biochar. The resulting biochar exhibited a large specificsurface area (933.39 m^(2)/g), a rich porous structure (1.044 cm3/g), and abundant active sites.Consequently, the prepared boron-doped porous biochar exhibited higher efficiency in adsorbingtetracycline with a maximum adsorption capacity of 413.223 mg/g, which significantlyexceeded that of unmodified biochar andmost commercial and reported adsorbents.The correlation analysis between the adsorption capacity and adsorbent characteristics revealedthat the formation of the –BCO_(2) group enhanced π–π electron donor–acceptor interactionsbetween boron-doped porous biochar and tetracycline. This mechanism mainlycontributed to the enhanced adsorption of tetracycline by boron-doped porous biochar. Additionally,the as-prepared boron-doped porous biochar exhibited broad applications in removingantibiotics (tetracycline), phenolics (bisphenol A), and dyes (methylene blue andrhodamine B). Moreover, the boron-doped porous biochar exhibited satisfactory stability,and its adsorption capacity can be nearly completely regenerated through simple heat treatment.This study provides new insights into the effectiveness of boron-doped carbonaceousmaterials in removing antibiotic contaminants. 展开更多
关键词 Antibiotic contaminants Adsorption Carbonaceous adsorbents Boron-doped porous biochar TETRACYCLINE
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Removal of Iron from Leached Geological Samples Using Polypropylene Waste Amidoxime-Based Radiation Grafted Adsorbent
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作者 Hafiz Zain Ul Aabidin Muhammad Inam Ul Hassan +2 位作者 Tariq Yasin Muhammad Zubair Rahim Asif Raza 《Journal of Polymer Materials》 2025年第1期141-150,共10页
Geological samples often contain significant amounts of iron,which,although not typically the target element,can substantially interfere with the analysis of other elements of interest.To mitigate these interferences,... Geological samples often contain significant amounts of iron,which,although not typically the target element,can substantially interfere with the analysis of other elements of interest.To mitigate these interferences,amidoximebased radiation grafted adsorbents have been identified as effective for iron removal.In this study,an amidoximefunctionalized,radiation-grafted adsorbent synthesized from polypropylene waste(PPw-g-AO-10)was employed to remove iron from leached geological samples.The adsorption process was systematically optimized by investigating the effects of pH,contact time,adsorbent dosage,and initial ferric ion concentration.Under optimal conditions-pH1.4,a contact time of 90 min,and an initial ferric ion concentration of 4500 mg/L-the adsorbent exhibited a maximum iron adsorption capacity of 269.02 mg/g.After optimizing the critical adsorption parameters,the adsorbent was applied to the leached geological samples,achieving a 91%removal of the iron content.The adsorbent was regenerated through two consecutive cycles using 0.2 N HNO_(3),achieving a regeneration efficiency of 65%.These findings confirm the efficacy of the synthesized PPw-g-AO-10 as a cost-effective and eco-friendly adsorbent for successfully removing iron from leached geological matrices while maintaining a reasonable degree of reusability. 展开更多
关键词 Removal of iron leach liquor geological samples POLYPROPYLENE radiation grafted adsorbent
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Design of Ultra‑Stable Solid Amine Adsorbents and Mechanisms of Hydroxyl Group‑Dependent Deactivation for Reversible CO_(2)Capture from Flue Gas
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作者 Meng Zhao Liang Huang +6 位作者 Yanshan Gao Ziling Wang Shuyu Liang Xuancan Zhu Qiang Wang Hong He Dermot O’Hare 《Nano-Micro Letters》 2025年第7期355-373,共19页
Although supported solid amine adsorbents have attracted great attention for CO_(2) capture,critical chemical deactivation problems including oxidative degradation and urea formation have severely restricted their pra... Although supported solid amine adsorbents have attracted great attention for CO_(2) capture,critical chemical deactivation problems including oxidative degradation and urea formation have severely restricted their practical applications for flue gas CO_(2) capture.In this work,we reveal that the nature of surface hydroxyl groups(metal hydroxyl Al–OH and nonmetal hydroxyl Si–OH)plays a key role in the deactivation mechanisms.The polyethyleneimine(PEI)supported on Al–OH-containing substrates suffers from severe oxidative degradation during the CO_(2) capture step due to the breakage of amine-support hydrogen bonding networks,but exhibits an excellent anti-urea formation feature by preventing dehydration of carbamate products under a pure CO_(2) regeneration atmosphere.In contrast,PEI supported on Si–OHcontaining substrates exhibits excellent anti-oxidative stability under simulated flue gas conditions by forming a robust hydrogen bonding protective network with Si–OH,but suffers from obvious urea formation during the pure CO_(2) regeneration step.We also reveal that the urea formation problem for PEI-SBA-15 can be avoided by the incorporation of an OH-containing PEG additive.Based on the intrinsic understanding of degradation mechanisms,we successfully synthesized an adsorbent 40PEI-20PEG-SBA-15 that demonstrates outstanding stability and retention of a high CO_(2) capacity of 2.45 mmol g^(−1) over 1000 adsorption–desorption cycles,together with negligible capacity loss during aging in simulated flue gas(10%CO_(2)+5%O_(2)+3%H_(2)O)for one month at 60–70℃.We believe this work makes great contribution to the advancement in the field of ultra-stable solid amine-based CO_(2) capture materials. 展开更多
关键词 CO_(2)capture Solid amine adsorbent Long-term stability Oxidative degradation Urea formation
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Uncovering the mask of sensitizers to switch on the TTA-UC emission by supramolecular host-vip complexation
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作者 Cheng He Renlan Huang +6 位作者 Lingling Wei Qiuhui He Jinbo Liu Jiao Chen Ge Gao Cheng Yang Wanhua Wu 《Chinese Chemical Letters》 2025年第4期183-187,共5页
Pt(Ⅱ)-salophen complexes(S-1~S-4) and 9,10-diphenylanthracene(DPA) tethering pillar[5]arene derivatives(A-1 and A-2) were synthesized to act as sensitizers and annihilators for triplet-triplet annihilation upconversi... Pt(Ⅱ)-salophen complexes(S-1~S-4) and 9,10-diphenylanthracene(DPA) tethering pillar[5]arene derivatives(A-1 and A-2) were synthesized to act as sensitizers and annihilators for triplet-triplet annihilation upconversion(TTA-UC), respectively. It turned out that the pyridine cation served as a mask for the excited state of the sensitizer, the triplet states of S-2 and S-3 were significantly quenched by photo-induced electron transfer(PET) with phosphorescence quantum yield quenched from 24.4% for S-4 to 9.3% for S-3,and therefore, both S-2 and S-3 led to negligible UC emissions when traditional annihilator DPA was used as the annihilator. Delightfully, when supramolecular annihilator A-1 and A-2 were employed to include the pyridine cation, PET was significantly inhibited and the triplet states of the sensitizers were activated,TTA-UC emission was therefore boosted. The UC quantum yield of A-2/S-3 system was up to 130 times higher than that of DPA/S-3 system, and the UC emission was switchable by the addition of competitive vips. 展开更多
关键词 Triplet state PHOTOSENSITIZER TTA-upconversion Host-vip complexation Molecular sensing
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New insight into the role of humic acid in Vis/Fe(Ⅲ)/PDS system: Synergistic effects of complexation and photosensitization
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作者 Xuejia Li Yang Liu +5 位作者 Jian Wei Yujia Xiang Xinruo Wang Hanchang Wang Heng Zhang Bo Lai 《Chinese Chemical Letters》 2025年第10期539-544,共6页
Humic acid(HA) as a natural reducing ligand was employed to accelerate the Fenton and Fenton-like processes, however, the potential role of photosensitivity was overlooked. This research showed that HA exhibits more s... Humic acid(HA) as a natural reducing ligand was employed to accelerate the Fenton and Fenton-like processes, however, the potential role of photosensitivity was overlooked. This research showed that HA exhibits more significant promotion for levofloxacin(LVF) degradation under light conditions compared to darkness. The study also proposed a mechanism involving complexation and photosensitization interactions. A strong inhibitor of ethylenediaminetetraacetic acid confirmed that the formation of organic-iron complexes was crucial. Firstly, it was proposed that complexed iron has a lower redox potential than free iron, which may be responsible for accelerating electron transfer from iron to peroxydisulfate(PDS). The density functional theory(DFT) calculations confirmed that complexed iron has a lower reaction energy barrier for PDS activation. Additionally, the excited state substances(^(*)HA and ^(*)LVF) can transfer electrons to Fe(Ⅲ) and PDS, and the generation of HA/LVF-Fe(Ⅲ)-PDS can accelerate this process. These findings could offer fresh perspectives on the combined elimination of contaminants through natural organic compounds and light exposure. 展开更多
关键词 HA promotion complexation PHOTO-FENTON Thermodynamic feasibility enhancement Photosensitive-LMCT
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Natural brown coal as an adsorbent for manganese removal from groundwater:A mechanistic and operational evaluation
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作者 Obiri-Nyarko F Darko DA +2 位作者 Quansah JO Asare SV Karikari AY 《Journal of Groundwater Science and Engineering》 2025年第4期371-385,共15页
This study investigates the potential of natural Brown Coal(BC)as a sustainable,cost-effective adsorbent for the removal of manganese(Mn2+)from contaminated groundwater.A series of batch adsorp-tion experiments was co... This study investigates the potential of natural Brown Coal(BC)as a sustainable,cost-effective adsorbent for the removal of manganese(Mn2+)from contaminated groundwater.A series of batch adsorp-tion experiments was conducted to assess the influence of key operational parameters—such as solution pH,2+initial Mn concentration,BC dosage,temperature,and the presence of competing ions—on 2+Mn removal efficiency.The environmental compatibility and regeneration potential of BC were also evaluated to deter-mine its practical viability for repeated use.To better understand the adsorption behaviour,equilibrium and kinetic data were analysed using established isotherm and kinetic models,while thermodynamic parameters were computed to assess the spontaneity and thermal characteristics of the adsorption process.Furthermore,geochemical modelling and comprehensive BC characterization—including surface morphology,miner-alogical and elemental composition,and functional group analysis—were 2+performed to elucidate Mn speciation under varying environmental conditions and to uncover the underlying adsorption mechanisms.2+Results showed that Mn removal efficiency increased with higher pH,temperature,and BC dosage,but 2+declined at elevated initial Mn concentrations due to active site saturation.The process was spontaneous 2 and endothermic,with the Langmuir isotherm model(R=0.994)and pseudo-second-order kinetic model 2(R=0.996)providing the best fit to experimental data.Mechanistic analysis indicated that chemisorption,2+primarily through ion exchange and inner-sphere complexation,was the dominant mode of Mn uptake.3+The presence of competing cations,especially Fe and Cu2+,2+significantly hindered Mn removal due to preferential binding.Importantly,BC exhibited strong reusability,maintaining over 80%removal effi-ciency across four adsorption–desorption cycles without evidence of secondary pollutants.These findings demonstrate the potential of natural BC as an efficient,reusable,and environmentally benign material for treating manganese-contaminated groundwater. 展开更多
关键词 SORPTION Surface complexation Ion exchange Geochemical modelling Heavy metals Secondary pollution
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Syntheses,structures,and catalytic performances of complexes with 4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid ligands
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作者 LING Weizhong LIN Jingyi +3 位作者 ZHU Jianglin LIANG Yuyi DAI Shanshan LI Yu 《无机化学学报》 北大核心 2026年第1期152-160,共9页
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(... Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3. 展开更多
关键词 complex dicarboxylic acid catalytic properties Knoevenagel reaction
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Enhanced separation of yttrium,erbium and thulium with P507 induced by complexation kinetics of DTPA
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作者 Na SUI Shu-kai MIAO +3 位作者 Hao SHEN Kai-hui CUI Jia-qi WANG Kun HUANG 《Transactions of Nonferrous Metals Society of China》 2025年第4期1338-1349,共12页
Based on a non-equilibrium kinetic extraction technique,the complexation kinetics of diethylenetriamine-pentaacetic acid(DTPA)with rare earth(RE)ions was investigated with different adding sequences of DTPA.The result... Based on a non-equilibrium kinetic extraction technique,the complexation kinetics of diethylenetriamine-pentaacetic acid(DTPA)with rare earth(RE)ions was investigated with different adding sequences of DTPA.The results indicated that the separation factors ofβTm/Er andβY/Er were higher when adding DTPA at the start of extraction than those before extraction.The extraction order for Y,Er and Tm was Tm>Y>Er.The root of discrepancy in complexation kinetics of Y,Er and Tm ions with DTPA and the enhanced kinetic separation mechanism were elucidated from the forward complex formation and reverse dissociation rates by the stopped-flow spectrophotometric technique.The apparent complexation rate constants began to decrease gradually with the increase of aqueous pH,while increased with increasing DTPA concentration.The emergence of extraction priority order as Tm>Y>Er was verified according to the calculated reaction kinetic constants of Y,Er and Tm at different pH values. 展开更多
关键词 rare earths extraction complexation kinetics diethylenetriaminepentaacetic acid(DTPA) stopped-flow spectrophotometric technique
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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Syntheses,crystal structures,catalytic and anti-wear properties of zinc(Ⅱ),nickel(Ⅱ)and cadmium(Ⅱ)complexes constructed from a terphenyl-tricarboxylate ligand
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作者 ZHAO Zhenghua LIU Yufeng +2 位作者 ZHANG Qing SHI Zifa GU Jinzhong 《无机化学学报》 北大核心 2026年第1期170-180,共11页
Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been construc... Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3. 展开更多
关键词 complexES tricarboxylic acid catalytic properties Knoevenagel condensation reaction anti-wear performance
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Corrigendum to“The complexation of insulin with sodium N-[8-(2-hydroxybenzoyl)amino]-caprylate for enhanced oral delivery:Effects of concentration,ratio,and pH”[Chinese Chemical Letters 33(2022)1889-1894]
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作者 Huixian Weng Lefei Hu +8 位作者 Lei Hu Yihan Zhou Aohua Wang Ning Wang Wenzhe Li Chunliu Zhu Shiyan Guo Miaorong Yu Yong Gan 《Chinese Chemical Letters》 2025年第8期674-674,共1页
The authors regret that an error in Fig.3E in this article was found while we reviewing the published data.An inadvertent mistake occurred in the process of assembling images.The picture of the Ms215μg/mL group was w... The authors regret that an error in Fig.3E in this article was found while we reviewing the published data.An inadvertent mistake occurred in the process of assembling images.The picture of the Ms215μg/mL group was wrongly placed. 展开更多
关键词 RATIO correction assembling imagesthe sodium n hydroxybenzoyl amino caprylate PH insulin complexation published dataan oral delivery
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Synthesis,structural characterization,electrocatalytic proton reduction,and fungicidal activity of thiazole‑containing di‑iron complexes
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作者 JIANG Chengyu LIU Xufeng 《无机化学学报》 北大核心 2026年第2期355-364,共10页
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo... This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4. 展开更多
关键词 THIAZOLE di‑iron complex crystal structure electrocatalytic proton reduction fungicidal activity
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CO_(2) capture performance of ZrO_(2)-doped Na_(2)CO_(3)/γ-Al_(2)O_(3) adsorbent
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作者 Zelin Xu Jiliang Ma +3 位作者 Xiaoping Chen Zhongji Song Daoyin Liu Cai Liang 《Journal of Environmental Sciences》 2025年第9期382-394,共13页
Sodium-based adsorbents(Na_(2)CO_(3)/γ-Al_(2)O_(3))exhibit significant potential for commercial utilization in CO_(2)capture.Nevertheless,the requirement for high desorption temperatures poses challenges in terms of ... Sodium-based adsorbents(Na_(2)CO_(3)/γ-Al_(2)O_(3))exhibit significant potential for commercial utilization in CO_(2)capture.Nevertheless,the requirement for high desorption temperatures poses challenges in terms of the high-quality heat needed for desorption.This study integrated ZrO_(2)doping into a sodium-based adsorbent to enhance its CO_(2)capture performance and lower its desorption temperature.The research investigated the CO_(2)adsorption capacity,reaction rate,and desorption characteristics of the ZrO_(2)-doped Na_(2)CO_(3)/γ-Al_(2)O_(3)adsorbents in detail.Additionally,the catalytic mechanism of ZrO_(2)was elucidated through Density Functional Theory calculations.The results showed that ZrO_(2)doping increased the adsorption rate and capacity of the adsorbent and reduced the desorption energy consumption.Desorption reaction activation energy reduced to 44.8 kJ/mol.The adsorbent doped with 3wt.%ZrO_(2)demonstrated the highest adsorption capacity and rate under optimal conditions,with a reaction temperature of 45℃,an adsorption capacity of 1.66 mmol/g,and a carbon conversion rate of 80.2%.ZrO_(2)acted as a catalyst,enhancing CO_(2)and H_(2)O adsorption,and facilitated CO_(2)desorption in the sodium-based adsorbent by forming[ZrO(OH)]^(+)and OH^(−)through H_(2)O adsorption activation.The lower energy barrier(0.17 eV)for the dissociative adsorption pathway of H_(2)O molecules on the ZrO_(2)surface further supported the role of ZrO_(2)in enhancing the overall adsorption performance of the adsorbent in the carbon capture process.Ultimately,the ZrO_(2)-doped Na_(2)CO_(3)/γ-Al_(2)O_(3)adsorbent was identified as having low desorption energy consumption,high adsorption capacity,and rate,offering potential cost reductions in CO_(2)capture and representing a promising adsorbent for this application. 展开更多
关键词 CO_(2)capture Sodium-based adsorbent Na_(2)CO_(3)/γAl_(2)O_(3) ZrO_(2)doped
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Image-free single-pixel semantic segmentation for complex scene based on multi-scale U-Net
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作者 Tengfei Liu Yanfeng Bai +4 位作者 Jianxia Chen Jintao Zhai Siqing Xiang Xianwei Huang Xiquan Fu 《Chinese Physics B》 2026年第1期440-447,共8页
Single-pixel imaging(SPI)receives widespread attention due to its superior anti-interference capabilities,and image segmentation technology can effectively facilitate its recognition and information extraction.However... Single-pixel imaging(SPI)receives widespread attention due to its superior anti-interference capabilities,and image segmentation technology can effectively facilitate its recognition and information extraction.However,the complexity of the target scene and plenty of imaging time in SPI make it challenging to achieve high-quality and concise segmentation.In this paper,we investigate the image-free intricate scene semantic segmentation in SPI.Using“learned”illumination patterns allows for the full extraction of the object's spatial information,thereby enabling pixel-level segmentation results through the decoding of the received measurements.Simulation and experimentation show that,in the absence of image reconstruction,the mean intersection over union(MIoU)of segmented image can reach higher than 85%,and the Dice coefficient(DICE)close to 90%even at the sampling ratio of 5%.Our approach may be favorable to applications in medical image segmentation and autonomous driving field. 展开更多
关键词 single-pixel imaging image-free deep learning complex scene
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Acute zonal occult outer retinopathy complex and angioid streaks:a case report
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作者 Zhen-Yu Liu Hang Zhang +1 位作者 Xiu-Li Sun Xiao-Yan Peng 《International Journal of Ophthalmology(English edition)》 2026年第1期193-196,共4页
Dear Editor,We present a case of acute zonal occult outer retinopathy(AZOOR)complex in a myopic patient with angioid streaks(ASs).A 19-year-old female has been experiencing visual field defects in her left eye for mor... Dear Editor,We present a case of acute zonal occult outer retinopathy(AZOOR)complex in a myopic patient with angioid streaks(ASs).A 19-year-old female has been experiencing visual field defects in her left eye for more than 3y.She was diagnosed with ASs and choroiditis at a local hospital.She has a seven-year history of bilateral high myopia.A fundus examination confirmed the presence of ASs and myopic fundus changes in both eyes.Multimodal imaging revealed an AZOOR complex in the left eye. 展开更多
关键词 myopic fundus changes zonal occult outer retinopathy azoor complex Angioid Streaks Acute Zonal Occult Outer Retinopathy MYOPIA fundus examination angioid streaks ass azoor complex
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Crystal structures of complexes of cyclobutanocucurbit[5]uril with Na^(+)/K^(+): Coordination state in different anionic environments
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作者 CHEN Wang WU Guixian +6 位作者 XIONG Yingying CHENG Ming ZHOU Mingming ZHANG Hui LIANG Zhengyun HUANG Dejin CHEN Minghua 《无机化学学报》 北大核心 2026年第1期161-169,共9页
The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when th... The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4. 展开更多
关键词 cucurbit[n]uril supramolecular chemistry uril cucurbit[n]uril-metal complexes
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Enhanced timing of a 113 km O-TWTFT link with complex maximum likelihood estimation process
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作者 Yu-Chen Fang Jian-Yu Guan +10 位作者 Qi Shen Jin-Jian Han Lei Hou Meng-Zhe Lian Yong Wang Wei-Yue Liu Ji-Gang Ren Cheng-Zhi Peng Qiang Zhang Hai-Feng Jiang Jian-Wei Pan 《Chinese Physics B》 2026年第1期244-249,共6页
Optical two-way time-frequency transfer(O-TWTFT),utilizing optical frequency comb carriers and linear optical sampling,effectively enables space-to-ground optical frequency standard comparisons.Previously reported det... Optical two-way time-frequency transfer(O-TWTFT),utilizing optical frequency comb carriers and linear optical sampling,effectively enables space-to-ground optical frequency standard comparisons.Previously reported detection sensitivities of O-TWTFTs were typically in the nanoWatt level,necessitating high-power optical frequency combs to compensate for significant losses in high-orbit satellite-to-ground passes.Such hardware-based solutions,while effective,tend to be costly.This paper presents a novel data post-processing algorithm to enhance sensitivity.Unlike previous timing methods,which depend solely on optical phase data and discard intensity information—resulting in elevated errors,especially under low-reception power,our approach employs complex least squares(CLS)estimation in the complex frequency domain.By preserving all intermediate data and avoiding noise from phase unwrapping,it achieves superior sensitivity and accuracy.Experiments over a 113-kilometer free-space link validate the algorithm's robustness,delivering a detection sensitivity of0.1 nanoWatts—over tenfold better than prior techniques—despite a 100-decibel link loss,comparable to Earth-Moon optical links. 展开更多
关键词 optical time-frequency transfer linear optical sampling frequency comb complex least squares
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