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Correction to:Electrochemical reconstruction:a new perspective on Sn metal-organic complex microbelts as robust anode for lithium storage
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作者 Jin-Ke Shen Nai-Teng Wu +7 位作者 Li-Yuan Wang Gang Jiang Dong-Lei Guo Jin Li Gui-Long Liu Hong-Yu Mi Huan Pang Xian-Ming Liu 《Rare Metals》 2025年第5期3591-3591,共1页
In this article the affiliation of Jin-Ke Shen,Nai-Teng Wu,Li-Yuan Wang,Gang Jiang,Jin Li,Gui-Long Liu,Xian-Ming Liu were incorrectly given as:State Key Laboratory of Chemistry and Utilization of Carbon Based Energy R... In this article the affiliation of Jin-Ke Shen,Nai-Teng Wu,Li-Yuan Wang,Gang Jiang,Jin Li,Gui-Long Liu,Xian-Ming Liu were incorrectly given as:State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources,School of Chemical Engineering and Technology,Xinjiang University,Urumqi 830046,China. 展开更多
关键词 electrochemical reconstruction metal organic complex microbelts robust anode chemical engineering lithium storage
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Design and synthesis of nitrogen-doped hexagonal NiCoO nanoplates derived from Ni-Co-MOF for high-performance electrochemical energy storage 被引量:4
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作者 Yan Li Yuying Shan Huan Pang 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第9期2280-2286,共7页
In order to further improve the potential application of nickel-cobalt oxide(NiCoO)in supercapacitors,we use controlled calcination of diffe rent Ni-Co-MOF([NiCo(HBTC)(4,4’-bipy)])composites to obtain five kinds of n... In order to further improve the potential application of nickel-cobalt oxide(NiCoO)in supercapacitors,we use controlled calcination of diffe rent Ni-Co-MOF([NiCo(HBTC)(4,4’-bipy)])composites to obtain five kinds of nickel doped NiCoO(N-NiCoO)with different Ni/Co molar ratio.These N-NiCoO materials with unique hexagonal nanoplates structure,high specific surface area and high porosity indicate high and stable electrochemical activity.In particular,N-NiCoO-2 with a Ni/Co molar ratio of 2:1 exhibits the highest 945.79 F/g specific capacitance at 1 A/g and a high cycle stability of only 6.7%attenuation after 5000 cycles.Apart from the certain percentage of NiCoO with higher conductivity,nitrogen doping provides more reactive sites and the specific porous hexagonal nanoplates structure of the product itself accelerate electron transfer and promote electrolyte diffusion can more effectively enhance the electrochemical performance.Therefore,N-NiCoO synthesized via a simple method exhibit exciting potential and can be used as an electrode material for supercapacitors with good performance. 展开更多
关键词 Ni-Co-MOF N-NiCoO SOLVOTHERMAL SUPERCAPACITORS Electrochemical performance
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Electrochemical Synthesis and Magnetic Studies of Ni-Fe-Co-Mn-Bi-Tm High Entropy Alloy Film 被引量:8
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作者 YAO Chen-zhong ZHANG Peng +2 位作者 TONG Ye-xiang XIA Dao-cheng MA Hui-xuan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第4期640-644,共5页
Amorphous Ni-Fe-Co-Mn-Bi-Tm high entropy alloy films were firstly prepared by potentiostatic electro- deposition. The results indicate that the six elements can be co-deposited in an organic system of DMF (N,N-dimeth... Amorphous Ni-Fe-Co-Mn-Bi-Tm high entropy alloy films were firstly prepared by potentiostatic electro- deposition. The results indicate that the six elements can be co-deposited in an organic system of DMF (N,N-dimethylformamide)-CH3CN. The surface of the film is composed of compact and uniform particles with triangular cone shape and a particle size of 100-200 nm. A simple face-centered-cubic structure is identified by XRD patterns after the films were annealed under Ar atmosphere. The annealed alloy film shows soft magnetic properties and the magnetization decreases with Fe content decreasing. 展开更多
关键词 High entropy alloy ELECTRODEPOSITION Magnetic property Heat treatment
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Active phase morphology engineering of NiMo/Al2O3 through La introduction for boosting hydrodesulfurization of 4,6-DMDBT 被引量:5
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作者 Ji-Xing Liu Xiang-Qi Liu +7 位作者 Ri-Xin Yan Ling-Feng Ji Hui-Fang Cheng Hui Liu Yan Huang Ming-Qing Hua Hua-Ming Li Wen-Shuai Zhu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1231-1237,共7页
Herein,we designed and constructed a mesoporous LaAlOx via a solvent evaporation induced self-assembly protocol.The structure and physicochemical property of the corresponding NiMo supported catalyst was analyzed by a... Herein,we designed and constructed a mesoporous LaAlOx via a solvent evaporation induced self-assembly protocol.The structure and physicochemical property of the corresponding NiMo supported catalyst was analyzed by a set of characterizations,and its catalytic activity was investigated for hydrodesulfurization(HDS)of 4,6-dimethyldibenzothiophene.It has confirmed that the incorporation of La profoundly facilitate the generation of“Type II”NiMoS phase by weakening the interaction of Mo–O–Al leakage and promoting the sulfidation of both Ni and Mo oxides as well as changing the morphology of Ni promoted MoS2 slabs,thereafter boosting the HDS performance substantially.The finding here may contribute to the fundamental understanding of structure-activity in ultra-deep desulfurization and inspire the advancement of highly-efficient HDS catalyst in future. 展开更多
关键词 NiMo supported Catalyst LaAlOx composites HYDRODESULFURIZATION MORPHOLOGY Reaction kinetics
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Quantum-chemical Study on the Structures and Properties of Uracil-BX_3 (X = F,Cl) Complexes 被引量:1
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作者 ZHANG Shi-Guo LI Hong YANG Pin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期947-956,共10页
For the uracil-BX3 (X = F, Cl) systems, geometries and binding energies have been calculated by using the Lee-Young-Parr correlation functionals (B3LYP) method of density functional theory (DFT) and the second-o... For the uracil-BX3 (X = F, Cl) systems, geometries and binding energies have been calculated by using the Lee-Young-Parr correlation functionals (B3LYP) method of density functional theory (DFT) and the second-order Moller-Plesset (MP2) method of ab initio at the 6- 311 +G^* or 6-311 ++G^* basis set. Four isomers were found for each system, and then the single-point energy evaluations were performed using the larger basis sets of (6-311 +G(2df, p) and aug-cc-pVDZ with DFF method. In the most stable isomer of uracil-BF3 or uracil-BCl3, the boron atom of BX3 (X = F, Cl) connects to the carbonyl oxygen O7 of uracil with a stabilization energy of -46.56 or -31.10 kJ/mol at the B3LYP/6-31 1+G^* level (BSSE corrected). The analyses for combining interaction between BX3 and uracil with the atom-in-molecule theory (AIM) and natural bond orbital method (NBO) have been performed. The results indicate that all isomers were formed with σ-p type interactions between uracil and BX3, in which the carbonyl oxygen offers its lone pair electrons to the empty p orbital of boron atom and the concomitances of charge transfer from uracil to BX3 occur. Moreover, there exists one or two hydrogen bonds in most isomers of uracil-BX3 system and these hydrogen bonds contribute to the stability of the complex systems. Frequency analysis suggests that the stretching vibration of BX3 undergoes a red shift in complexes. Uracil-BF3 complex is more stable than uracil-BCl3 although the distance of B-O is shorter in the latter. Besides, the conversion mechanisms between different isomers of uracil-BF3 have been obtained. 展开更多
关键词 B3LYP MP2 intermolecular interaction uracil-BF3 complex uracil-BCl3 complex
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Electrochemical reconstruction: a new perspective on Sn metal-organic complex microbelts as robust anode for lithium storage 被引量:1
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作者 Jin-Ke Shen Nai-Teng Wu +7 位作者 Li-Yuan Wang Gang Jiang Dong-Lei Guo Jin Li Gui-Long Liu Hong-Yu Mi Huan Pang Xian-Ming Liu 《Rare Metals》 SCIE EI CAS CSCD 2024年第1期76-86,共11页
Tin-based materials with high theoretical capacity and suitable working voltage are ideal anode materials for lithium-ion batteries(LIBs). However, to overcome their shortcomings(volume expansion and inferior stabilit... Tin-based materials with high theoretical capacity and suitable working voltage are ideal anode materials for lithium-ion batteries(LIBs). However, to overcome their shortcomings(volume expansion and inferior stability), the preparation processes are usually complicated and expensive. Herein, a tin-based metal-organic complex(tin 1,2-benzenedicarboxylic acid, Sn-BDC)with one-dimensional microbelt morphology is synthesized by a facile, rapid and low-cost co-precipitation method, and served as anode material for LIBs without any post-treatment. Sn-BDC exhibits a high reversible capacity with609/440 m Ah·g^(-1) at 50/2000 m A·g^(-1), and robust cycling stability of 856 m Ah·g^(-1) after 200 cycles at 200 m A·g^(-1),which are obviously superior to that of the Sn Ox/C counterparts. Moreover, an electrochemical reconstruction perspective on the lithium storage mechanism of Sn-BDC is proposed by systematic ex-situ characterizations. The reconstructed SnO_(2) replaces Sn-BDC and becomes the active material in the subsequent cycles. As the by-product of the lithiation reaction, the formed Li-based metal-organic complex(Li-BDC, wrapped around the reconstructed SnO_(2)) plays an important role in alleviating volume expansion and accelerating the charge transfer kinetics.This work is beneficial to design and construct the new electrode materials based on the electrochemical reconstruction for advanced LIBs. 展开更多
关键词 Electrochemical reconstruction Metal-organic complex ANODE Lithium storage mechanism Lithium-ion batteries
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Identification of phytochemical compounds in Calophyllum inophyllum leaves
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作者 David Febrilliant Susanto Hakun Wirawasista Aparamarta +1 位作者 Arief Widjaja Setiyo Gunawan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第9期773-781,共9页
Objectives: To investigate the proximate composition, mineral content, and phytochemical compounds in Calophyllum inophyllum(C. inophyllum) leaves. Moreover,isolation and identification of pyrene were also performed.M... Objectives: To investigate the proximate composition, mineral content, and phytochemical compounds in Calophyllum inophyllum(C. inophyllum) leaves. Moreover,isolation and identification of pyrene were also performed.Methods: C. inophyllum leaves were extracted with methanol by percolation methods.The proximate composition of C. inophyllum leaves was analyzed by standard methods.Mineral contents in this plant were analyzed by using atomic absorption spectrophotometer. Phytochemical screening and analysis of this plant were performed by spectrophotometric method. Washing method with carbon disulfide was used for isolating dihydropyrene compound from C. inophyllum leaves extracts.Results: The result revealed that C. inophyllum leaves contained 11.24% moisture,4.75% ash, 6.43% crude protein, 23.96% crude fiber, 9.91% carbohydrate, and energy(79.17 kcal/100 g). The leaves also contained 0.007% iron, 1.240% calcium, 0.075%sodium, 0.195% magnesium, 0.100% ppm potassium, and 0.040% phosphorus. Moreover, 11.51% alkaloid, 2.48% triterpenoid, 2.37% flavonoid, 7.68% tannin, 2.16%saponin, 2.53% polyphenol, were identified in the methanolic crude extracts of C. inophyllum leaves. It was found that trans-2-[2-(trifluoromethyl)phenyl]-10 b,10 c-dimethyl-10 b,10 c-dihydropyrene was obtained at purity of 79.18%(22.17% yield)from C. inophyllum leaves.Conclusions: C. inophyllum leaves may be used as a good source of fiber. It was found that C. inophyllum leaves have the potential as herbal drugs due to their phytochemical content. The separation, isolation, and purification of bioactive compounds from this methanolic crude extract and their biological activity are under further investigation. 展开更多
关键词 Calophyllum inophyllum leaves Crude extracts Proximate composition Mineral composition PHYTOCHEMICAL
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A controllable preparation of two-dimensional cobalt oxalate-based nanostructured sheets for electrochemical energy storage
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作者 Fancheng Sun Qing Li +6 位作者 Yang Bai Guangxun Zhang Shasha Zheng Maoying Peng Xudong Chen Nuo Lin Huan Pang 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第6期3249-3254,共6页
Well-defined two-dimensional(2D)cobalt oxalate(CoC_(2)O_(4)·2H_(2)O)nanosheets exhibit more excellent property than common bulk cobalt oxalate due to high specific surface areas and high-efficient transport of io... Well-defined two-dimensional(2D)cobalt oxalate(CoC_(2)O_(4)·2H_(2)O)nanosheets exhibit more excellent property than common bulk cobalt oxalate due to high specific surface areas and high-efficient transport of ion and electron.However,the delicate control of the 2D morphology of CoC_(2)O_(4)·2H_(2)O during their synthesis remains challenging.Herein,2D CoC_(2)O_(4)·2H_(2)O nanosheets(M1),grown by straightforward chemical precipitation,can be tuned from three-dimensional(3D)structure during their synthesis with no templates or capping agents.This control is obtained by rationally changing the ratio of reactants with ethylene glycol as solvent.Moreover,Co_(3)O_(4)/CoC_(2)O_(4)composites(M1-250)have been fabricated through low-temperature thermal treatment of the M1 precursor in air,which possess porous surfaces with the 2D morphology maintained.Benefiting from the porous surfaces,more redox-active sites and better electrical conductivity of Co_(3)O_(4),the constructed M1-250//AC aqueous device manifest improved kinetics of the electrochemistry process with energy density of 27.9 Wh/kg at 550.7 W/kg and good cycling stability with sustaining 73.0 m Ah/g after 5000 cycles. 展开更多
关键词 Two-dimensional nanosheets Cobalt oxalate Co_(3)O_(4) Energy storage Capacity
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Biomimetic synthesis of all-inclusive organic-inorganic nanospheres for enhanced electrochemical immunoassay
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作者 Luyuan Tian Yuxiao Ma +4 位作者 Ming Li Qiaorong Tang Luyang Miao Bing Geng He Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第5期1159-1161,共3页
A friendly biomimetic process was adopted for the mild preparation of"all-inclusive"organic-inorganic nanospheres,which effectively integrate biorecognition function and signal amplification function.The res... A friendly biomimetic process was adopted for the mild preparation of"all-inclusive"organic-inorganic nanospheres,which effectively integrate biorecognition function and signal amplification function.The resulted Ca3(PO4)2-Ab2-BSA nanospheres were employed as signal labels for enhancing detection of nuclear matrix protein 22(NMP 22).The fabricated electrochemical immunosensor exhibited a linear range(0.08-77.00 U/mL)and an ultralow limit of detection(0.01 U/mL)towards NMP 22,which can be taken as a promising tool for clinical diagnosis of bladder cancer. 展开更多
关键词 Nuclear matrix protein 22 Biomimetic process Electrochemical immunosensor Limit of detection
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Synthesis of carbon nitride in moist environments:A defect engineering strategy toward superior photocatalytic hydrogen evolution reaction
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作者 Shuquan Huang Feiyue Ge +5 位作者 Jia Yan Hongping Li Xingwang Zhu Yuanguo Xu Hui Xu Huaming Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期403-413,共11页
Intimate understanding of the synthesis-structure-activity relationships is an accessible pathway to overcome the intrinsic challenges of carbon nitride(g-C_(3)N_(4))photocatalysts.This work looks in the effects of hu... Intimate understanding of the synthesis-structure-activity relationships is an accessible pathway to overcome the intrinsic challenges of carbon nitride(g-C_(3)N_(4))photocatalysts.This work looks in the effects of humidity of the synthesis process to the morphology,chemical structure,band structure as well as the photocatalytic activity of g-C_(3)N_(4) materials.Four g-C_(3)N_(4) samples were prepared by heating melem in four gas environments:dry Ar,dry Air,moist Ar and moist Air.The photocatalytic activity measurements revealed that the samples synthesized in moist inert and oxidic gases environments displayed 20 and 10 times the photocata lytic H_(2) evolution activity of the samples synthesized in dry inert and oxidic gases environments,respectively.The reasons for this remarkable variety in photocata lytic activities had been through investigated.After all,the terminations of the carbon vacancies were identified as the dominant factor in enhancing H_(2) evolution performance.The work here thus demonstrating an example of defect engineering. 展开更多
关键词 H_(2)evolution g-C_(3)N_(4) Carbon vacancy Terminal functional groups
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Review of Core-shell structure zeolite-based catalysts for NO_(x)emission control 被引量:1
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作者 Lingfeng Jia Jixing Liu +2 位作者 Huifang Cheng Zhen Zhao Jian Liu 《Journal of Environmental Sciences》 2025年第4期451-465,共15页
Nitrogen oxides(NO_(x))from diesel engine exhaust,is one of the major sources of environmental pollution.Currently,selective catalytic reduction with ammonia(NH_(3)-SCR)is considered to be the most effective protocol ... Nitrogen oxides(NO_(x))from diesel engine exhaust,is one of the major sources of environmental pollution.Currently,selective catalytic reduction with ammonia(NH_(3)-SCR)is considered to be the most effective protocol for reducing NO_(x)emissions.Nowadays,zeolitebased NH_(3)-SCR catalysts have been industrialized and widespread used in this field.Nevertheless,with the increasingly stringent environmental regulations and implementation of the requirement of“zero emission”of diesel engine exhaust,it is extremely urgent to prepare catalysts with superior NH_(3)-SCR activity and exceptional resistance to poisons(SO2,alkali metals,hydrocarbons,etc.).Core-shell structure zeolite-based catalysts(CSCs)have shown great promise in NH_(3)-SCR of NO_(x)in recent years by virtue of its relatively higher low-temperature activity,broader operation temperature window and outstanding resistance to poisons.This review mainly focuses on the recent progress of CSCs for NH_(3)-SCR of NO_(x)with three extensively investigated SSZ-13,ZSM-5,Beta zeolites as cores.The reaction mechanisms of resistance to sulfur poisoning,alkali metal poisoning,hydrocarbon poisoning,and hydrothermal aging are summarized.Moreover,the important role of interfacial effect between core and shell in the reaction of NH_(3)-SCR was clarified.Finally,the future development and application outlook of CSCs are prospected. 展开更多
关键词 NH_(3)-SCR ZEOLITE Core-shell structure RESISTANCE Interfacial effects
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CoTCPP integrates with BiOBr microspheres for improved solar-driven CO_(2)reduction performance
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作者 Lina Li Yi Zhang +7 位作者 Gaopeng Liu Tiange Wei Junze Zhao Bin Wang Mengxia Ji Yuanbin She Jiexiang Xia Huaming Li 《Green Energy & Environment》 SCIE EI CAS 2025年第1期193-202,共10页
CO_(2) photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse effect.Herein,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)h... CO_(2) photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse effect.Herein,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)has been integrated with BiOBr microspheres and formed the CoTCPP/BiOBr composite.The as-prepared CoTCPP/BiOBr-2 composite shows optimized photocatalytic performance for CO_(2) conversion into CO and CH_(4) upon irradiation with 300 W Xe lamp,which is 2.03 and 2.58 times compared to that of BiOBr,respectively.The introduced CoTCPP significantly enhanced light absorption properties,promoted rapid separation of photogenerated carriers and boosted the chemisorption of CO_(2) molecules.The metal Co^(2+) at the center of the porphyrin molecules also acts as adsorption center for CO_(2) molecules,accelerating the CO_(2) conversion into CO and CH_(4).The possible mechanism of CO_(2) photoreduction was explored by in-situ FT-IR spectra.This work offers a new possibility for the preparation of advanced photocatalysts. 展开更多
关键词 BiOBr CoTCPP CO_(2)photoreduction Carriers transfer CO_(2)adsorption-activation
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Detection of Curcumin by Nitrogen and Phosphorus Co-doped Green Emitting Carbon Dots
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作者 CAI Yipeng SUN Ning +2 位作者 YAN Chao SONG Shiyu SONG Shengmei 《分析科学学报》 北大核心 2025年第6期643-652,共10页
Nitrogen-phosphorus co-doped carbon dots(N,P-CDs)were synthesized via a one-step hydrothermal method using p-phenylene diisocyanate,ethylenediamine,and concentrated phosphoric acid as raw materials.The morphology,stru... Nitrogen-phosphorus co-doped carbon dots(N,P-CDs)were synthesized via a one-step hydrothermal method using p-phenylene diisocyanate,ethylenediamine,and concentrated phosphoric acid as raw materials.The morphology,structure,and optical properties of the N,P-CDs were characterized in detail.The N,P-CDs exhibit excellent water solubility,with optimal excitation and emission wavelengths of 392 nm and 520 nm,respectively.A novel fluorescence method for detection of curcumin was developed,demonstrating a linear range of 3.50-242.24μmol/L and a detection limit of 0.086μmol/L.When applied to the detection of curcumin in real water samples and chili powder seasoning,the method achieved recovery between 94.48%and 105.82%,and with the relative standard deviations(RSDs)ranging from 0.17%to 0.62%.These results highlight that the constructed fluorescence analysis method based on the N,P-CDs has the potential for the accurate and reliable detection of curcumin in real-world samples. 展开更多
关键词 N and P co-doped carbon dots(N P-CDs) Green fluorescence CURCUMIN
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Tailored design of novel Co^(0)-Co^(δ+)dual phase nanoparticles for selective CO_(2) hydrogenation to ethanol
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作者 Subhasis Das Ganapati D.Yadav 《Journal of Environmental Sciences》 2025年第3期598-615,共18页
Catalytic hydrogenation of CO_(2)to ethanol is a promising solution to address the greenhouse gas(GHG)emissions,but many current catalysts face efficiency and cost challenges.Cobalt based catalysts are frequently exam... Catalytic hydrogenation of CO_(2)to ethanol is a promising solution to address the greenhouse gas(GHG)emissions,but many current catalysts face efficiency and cost challenges.Cobalt based catalysts are frequently examined due to their abundance,cost-efficiency,and effectiveness in the reaction,where managing the Co^(0)to Co^(δ+)ratio is essential.In this study,we adjusted support nature(Al_(2)O_(3),MgO-MgAl_(2)O_(4),and MgO)and reduction conditions to optimize this balance of Co^(0)to Co^(δ+)sites on the catalyst surface,enhancing ethanol production.The selectivity of ethanol reached 17.9%in a continuous flow fixed bed micro-reactor over 20 mol%Co@MgO-MgAl_(2)O_(4)(CoMgAl)catalyst at 270°C and 3.0 MPa,when reduced at 400°C for 8 h.Characterisation results coupled with activity analysis confirmed that mild reduction condition(400°C,10%H_(2)balance N_(2),8 h)with intermediate metal support interaction favoured the generation of partially reduced Co sites(Co^(δ+)and Co^(0)sites in single atom)over MgO-MgAl_(2)O_(4)surface,which promoted ethanol synthesis by coupling of dissociative(CHx^(∗))/non-dissociative(CHxO^(∗))intermediates,as confirmed by density functional theory analysis.Additionally,the CoMgAl,affordably prepared through the coprecipitation method,offers a potential alternative for CO_(2)hydrogenation to yield valuable chemicals. 展开更多
关键词 CO_(2)hydrogenation ETHANOL Co-based catalysts Metal support ineraction DFT analysis
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Microwave-Assisted Synthesis, Characterization, and Performance Assessment of Lemongrass-Derived Activated Carbon for Removal of Fe and Mn from Acid Mine Drainage
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作者 Lailan Nimah Sri Rachmania Juliastuti Mahfud Mahfud 《Journal of Renewable Materials》 2025年第11期2169-2190,共22页
This study evaluates the effectiveness of microwave technology in producing activated carbon from lemongrass waste,an underutilized agricultural byproduct.Microwave-assisted production offers faster heating,lower ener... This study evaluates the effectiveness of microwave technology in producing activated carbon from lemongrass waste,an underutilized agricultural byproduct.Microwave-assisted production offers faster heating,lower energy consumption,and better process control compared to conventionalmethods.It also enhances pore development,resulting in larger,cleaner,and more uniform pores,making the activated carbon more effective for adsorption.The microwave-assisted process significantly accelerates production,reducing the required time to just 10 min at a power of 400 W.Activated carbon derived from lemongrass waste at 400 W exhibits a water absorption capacity of 7.88%,ash content of 5.51%,volatile matter of 6.96%,fixed carbon of 75.79%,and an iodine number of 790.97 g iodine/100 g.Scanning Electron Microscopy(SEM)analysis confirms the formation of larger,cleaner,and smoother pores,contributing to increased porosity and pore size.Additionally,Energy Dispersive X-ray(EDX)analysis identifies key elements in the lemongrass waste,with carbon being the dominant component at 75.57%.The Brunauer-Emmett-Teller(BET)surface area is measured at 818 m^(2)/g,with an average pore diameter of 1.91 nm,classifying the material as microporous.The activated carbon,meeting quality standards,is applied as an adsorbent in acid mine drainage(AMD)treatment,with varying mass concentrations introduced intowastewater samples.Adsorption tests confirmthat the microparticle carbon adsorption profile follows the Langmuir model,indicating a monolayer adsorption process.Furthermore,adsorption kineticswere analyzed over different time intervals,revealing that the process alignswith both pseudo-first-order(PFO)and pseudo-second-order(PSO)models,with all cases predominantly following the PFO rate equation. 展开更多
关键词 Microwave bio-adsorbent ADSORPTION metal ions acid mine drainage
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Decoding the mechanism of P450-catalyzed aromatic hydroxylation:Uncovering the arene oxide pathway and insights into the regioselectivity 被引量:1
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作者 Qun Huang Xuan Zhang +8 位作者 Guangwu Sun Rui-ying Qiu Lan Luo Cuizhen Wang Longwei Gao Bing Gao Bo Chen Binju Wang Jian-bo Wang 《Chinese Journal of Catalysis》 2025年第3期420-430,共11页
P450 enzymes-catalyzed aromatic hydroxylation plays an important role in detoxification,biosynthesis,and potential carcinogenic effect of aromatic compounds.Though it has been explored for decades,the actual process o... P450 enzymes-catalyzed aromatic hydroxylation plays an important role in detoxification,biosynthesis,and potential carcinogenic effect of aromatic compounds.Though it has been explored for decades,the actual process of aromatic hydroxylation and mechanism of regioselectivity catalyzed by cytochrome P450 monooxygenases remained ambiguous.Here,we have resolved these issues.With a stable chiral organofluorine probe,and especially with X-ray data of two isolated arene oxides derivatives,we demonstrate that an arene oxide pathway is definitely involved in P450-catalyzed aromatic hydroxylation.By the capture,isolation,identification and reactivity exploration of the arene 1,2-oxide and arene 2,3-oxide intermediates,together with advanced QM calculations,the mechanism of how two intermediates go to the same product has been elucidated.In addition to the model substrate,we also confirmed that an arene oxide intermediate is involved in the P450-catalyzed hydroxylation pathway of a natural product derivative methyl cinnamate,which indicates that this intermediate appears to be universal in P450-catalyzed aromatic hydroxylation.Our work not only provides the most direct evidence for the arene oxide pathway and new insights into the regioselectivity involved in P450-catalyzed aromatic hydroxylation,but also supplies a new synthetic approach to achieve the dearomatization of aromatic compounds. 展开更多
关键词 Aromatic hydroxylation Cytochrome P450 Arene oxide Regioselectivity DEAROMATIZATION
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Metal-organic framework Cu-BTC for overall water splitting: A density functional theory study
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作者 Xu Huang Kai-Yin Wu +2 位作者 Chao Su Lei Yang Bei-Bei Xiao 《Chinese Chemical Letters》 2025年第4期552-557,共6页
Metal-organic framework(MOF) has been widely applied in photocatalysis, which is significant for addressing energy crises and environmental issues. Based on density functional theory calculations,the performances of C... Metal-organic framework(MOF) has been widely applied in photocatalysis, which is significant for addressing energy crises and environmental issues. Based on density functional theory calculations,the performances of Cu-BTC, a copper-based MOF, and its derivatives Cu TM-BTC via the substitution of transition metal(TM) elements at the Cu site for photocatalytic overall water splitting(POWS) have been studied. POWS of Cu-BTC suffers from the sluggish hydrogen evolution reaction due to the large overpotential of 2.02 V and limited solar utilization due to a wide HOMO-LUMO gap of 4.11 e V. Via TM substitution, the HOMO-LUMO gap narrows but still satisfies the redox potentials when taken 3d-TM of Cr, Fe, Co or Ni, 4d-TM of Rh or Pd, or 5d-TM of Re or Pt into consideration, benefiting for the light absorption. Furthermore, Cr and Re could serve as active sites for hydrogen evolution with remarkably lowered overpotentials of 0.79 V and 0.28 V, respectively;similarly, oxygen evolution activities could be enhanced by Fe, Co and Rh because of their reduced overpotentials which are less than 0.5 V. Therefore,our findings pave guidance for designing Cu-BTC derivatives in overall water splitting. 展开更多
关键词 Metal-organic framework Density functional theory Cu-BTC PHOTOCATALYSIS Overall water splitting
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Mixed Quantum-Classical Approaches to Electron Transmission through Chiral Molecules
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作者 Jiayue Han Yu Wang Wenjie Dou 《Chinese Journal of Chemical Physics》 2025年第6期833-844,I0238,共13页
The chiral-induced spin selectivity(CISS)effect has attracted widespread interest due to its potential applications in spintronics.However,the influence of electron-vibration coupling on spin polarization has no unifi... The chiral-induced spin selectivity(CISS)effect has attracted widespread interest due to its potential applications in spintronics.However,the influence of electron-vibration coupling on spin polarization has no unified theoretical description.In this work,we revisit the widely used model proposed by 100%Jonas Fransson[Phys.Rev.B 102,235416(2020)]with two mixed quantum-classical approaches,namely mean-field(MF)dynamics and surface hopping(SH).Our results show that,in the absence of electron-vibration coupling,the transient spin polarization vanishes for short molecular chains or without spin-orbit coupling(SOC).For longer chains and stronger SOC,the polarization exhibits coherent oscillations reaching up to.When electron-vibration coupling is included,pronounced spin polarization emerges only at early femtosecond timescales,whose magnitude increases with SOC strength and chain length but decreases as the electron-vibration coupling grows.On picosecond timescales,the polarization decays and fluctuates narrowly around zero,yielding a negligible long-time average.These findings indicate that electron-vibration coupling generally suppresses spin polarization,in contrast to predictions in previous studies.We suggest that alternative or extended theoretical frameworks are required to elucidate the key role of electron-vibration coupling in the CISS effect. 展开更多
关键词 Chiral-induced spin selectivity Nonadiabatic dynamics Mixed quantum-classical approaches
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Investigation of water structure and proton transfer within confined graphene by ab initio molecule dynamics and multiscale data analysis
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作者 Heng-Su Liu Xi-Ming Zhang +2 位作者 Ge-Hao Liang Shisheng Zheng Jian-Feng Li 《Chinese Journal of Structural Chemistry》 2025年第6期41-49,共9页
The structure of water and proton transfer under nanoscale confinement has garnered significant attention due to its crucial role in elucidating various phenomena across multiple scientific disciplines.However,there r... The structure of water and proton transfer under nanoscale confinement has garnered significant attention due to its crucial role in elucidating various phenomena across multiple scientific disciplines.However,there remains a lack of consensus on fundamental properties such as diffusion behavior and the nature of hydrogen bonding in confined environments.In this work,we investigated the influence of confinement on proton transfer in water confined within graphene sheets at various spacings by ab initio molecule dynamic and multiscale analysis with time evolution of structural properties,graph theory and persistent homology.We found that reducing the graphene interlayer distance while maintaining water density close to that of bulk water leads to a decrease in proton transfer frequency.In contrast,reducing the interlayer distance without maintaining bulk-like water density results in an increase in proton transfer frequency.This difference is mainly due to the confinement conditions:when density is unchanged,the hydrogen bond network remains similar with significant layering,while compressive stress that increases density leads to a more planar hydrogen bond network,promoting faster proton transfer.Our findings elucidate the complex relationship between confinement and proton transfer dynamics,with implications for understanding proton transport in confined environments,relevant to energy storage and material design. 展开更多
关键词 Molecular dynamics GRAPHENE Confined water Graph theory Persistent homology
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Grafting Modification of Cellulose Nanofibril with 2-(N,N-Dimethylamino)Ethyl Methacrylate and 2-Hydroxyethyl Methacrylate as a Barrier-Improved Coating for Paper-Based Food Packaging
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作者 Noverra Mardhatillah Nizardo Alifah Nurul Saffanah +4 位作者 Annisa Fitri Salsabila Amanda Aurellia Putri Aniek Sri Handayani Azizah Intan Pangesty Mochamad Chalid 《Journal of Renewable Materials》 2025年第6期1209-1227,共19页
Food packaging is becoming popular as the consumption of ready-to-eat food products rises.Easyto-use,non-biodegradable plastic packaging is commonly used in food packaging,contributing to the deteriorating environment... Food packaging is becoming popular as the consumption of ready-to-eat food products rises.Easyto-use,non-biodegradable plastic packaging is commonly used in food packaging,contributing to the deteriorating environmental situation.This issue increases the concern for the environment and encourages the usage of alternative materials.Cellulose nanofibrils(CNF)are abundant and biodegradable,which makes them ideal candidates to replace plastic coatings.The ability to form H-bonds between the hydroxyl groups makes coated paper with CNF have good strength,but poor barrier properties.The barrier properties can be improved by grafting DMAEMA or HEMA onto CNF(CNF-g-PDMAEMA and CNF-g-PHEMA,respectively).Thus,the objective of this study was to modify CNF chemically to enhance the barrier properties of the food packaging paper.It was found that paper coated with CNFg-PDMAEMA and CNF-g-PHEMA exhibited improvements in mechanical and barrier properties while maintaining the desired viscosity for the coating process.The water contact angle increased for paper coated with CNF-g-PHEMA and CNF-g-PDMAEMA,reaching a maximum of 97.51°and 92.58°,respectively with the decreasing Cobb_(60) values by 49% and 11%.The oil absorption was also reduced for both coated papers compared to the blank paper.Mechanical properties improved,as indicated by a 3% increase in tensile strength for paper coated with CNF-g-PHEMA and a 5% for paper coated with CNF-g-PDMAEMA.The results indicated significant potential for the application of modified CNF in coatings for food packaging paper.Noteworthy,the grafting process should be improved to enhance the mechanical and barrier properties of the coated paper. 展开更多
关键词 Cellulose nanofibril GRAFTING biopolymer modification paper coating barrier properties
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