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A Novel Green Preparation ofα,α′-Bis(substituted benzylidene)-cycloalkanones Promoted by FeCl3·6H2O in Ionic Liquid 被引量:5
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作者 Xin Ying ZHANG, Xue Sen FAN, Hong Ying NIU, Jian Ji WANGSchool of Chemical and Environmental Sciences, Henan Normal University, Key Laboratory ofEnvironmental Science and Engineering of Henan Education Department,Xinxiang 453002 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第10期1005-1007,共3页
a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] a... a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] and iron(III) chloride hexahydrate can be quantitatively recovered and be reused effectively for many times. Compared with the known methods, this novel process has the advantage of being an envkonmentally benign process together with good yields and mild reaction conditions. 展开更多
关键词 Ionic liquid a a'-bis(substituted benzylidene)cycloalkanones iron(III) chloride hexahydrate.
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Sodium-Modified Fluorapatite: A Mild and Efficient Reusable Catalyst for the Synthesis of <i>α,α</i>’-Bis(Substituted Benzylidene) Cycloalkanones under Conventional Heating and Microwave Irradiation
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作者 Bahija Mounir Fathallaah Bazi +2 位作者 Abddelfetah Mounir Mohamed Zahouily Hamid Toufik 《Green and Sustainable Chemistry》 2018年第2期156-166,共11页
A versatile and environmentally friendly method for α,α’-bis(substituted ben-zylidene) cycloalkanones has been developed using a heterogeneous catalysis technology. We have synthesized a series of the α,α’-bis(s... A versatile and environmentally friendly method for α,α’-bis(substituted ben-zylidene) cycloalkanones has been developed using a heterogeneous catalysis technology. We have synthesized a series of the α,α’-bis(substituted benzylidene) cycloalkanones, a biologically important class of compounds, via the cross aldol condensation between arylaldehydes and cycloketones using sodium-modified fluorapatite (Na/FAP) as a highly efficient solid catalyst under conventional heating in aqueous media and solventless conditions under microwave. Catalyst reuse, ease of separation of the pure product, and high yields are some of the unique features of this process. Shorter reaction times (4 - 7 min) and higher yields (80% - 94%) were achieved under microwave irradiation conditions. 展开更多
关键词 Green Chemistry α α’-bis(substituted Benzylidene) CYCLOALKANONES Microwaves Irradiation Conventional Heating Aqueous Media FLUORAPATITE Activated by SODIUM Nitrate (Na/FAP)
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Synthesis of Substituted u-Oxo-bis[tetra-phenyl porphyrinatoiron] Compounds from Free Base Porphyrins by a One-pot Method 被引量:2
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作者 佘远斌 冯连顺 +1 位作者 王爱欣 李修艳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第3期369-372,共4页
A novel method for synthesis of substituted μ-oxo-bis[tetraphenyl porphyrinatoiron] compounds ([TRPPFe]2O) based on the reaction among free base porphyrins (TRPPH2), FeSO4·7H2O and H2O in one pot was proposed an... A novel method for synthesis of substituted μ-oxo-bis[tetraphenyl porphyrinatoiron] compounds ([TRPPFe]2O) based on the reaction among free base porphyrins (TRPPH2), FeSO4·7H2O and H2O in one pot was proposed and investigated. Four kinds of [TRPPFe]2O were synthesized by this novel synthetic method, and their structures were characterized by elemental analysis, infrared spectra and UV-vis spectroscopy. The reaction conditions, including the effect of different iron salts on the formation of [TRPPFe]2O, the reaction time between FeSO4·7H2O and TRPPH2, the molar ratio of FeSO4·7H2O/TRPPH2 as well as the volume ratio of H2O/DMF, were investigated. The [TRPPFe]2O yield of 93%-98% could be obtained under the following optimal conditions: the reaction time of FeSO4·7H2O with TRPPH2 was about 10 h, the molar ratio of FeSO4·7H2O/TRPPH2 about 5︰1, and the volume ra-tio of H2O/DMF exceeded 2︰1. Further research indicated that only TRPPFeCl were formed once FeSO4·7H2O was replaced by FeCl2·4H2O, the reason of which might be that halogen ions in iron salts interfered the formation of [TRPPFe]2O, suggesting that halogen ions should be avoided in this novel synthetic method. 展开更多
关键词 一锅法 卟啉配体 合成 μ-氧代四苯基双核铁卟啉
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Formation of α,α'-Bis(substituted benzylidene)cycloalkanones from Masked Aldehydes Promoted by Samarium(III) Triiodide
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作者 XiaoXiaWANG YongMinZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第5期511-514,共4页
Diacetates 1 and N-[(1-benzotriazol-l-yl)alkyl]amides 2, both masked forms of aldehydes, could undergo deprotection and condensation with cycloalkanones in a one-pot procedure promoted by samarium(III) iodide (SmI3) ... Diacetates 1 and N-[(1-benzotriazol-l-yl)alkyl]amides 2, both masked forms of aldehydes, could undergo deprotection and condensation with cycloalkanones in a one-pot procedure promoted by samarium(III) iodide (SmI3) to afford α,α'-bis(substituted benzylidene) cycloalkanones in good yields. 展开更多
关键词 Samarium(III) triiodide α α'-bis(substituted benzylidene)cycloalkanone 1 1-diacetate N-[(l-benzotriazol-1-yl)alkyl]amide. Quinolone antibacterial agents have emerged as one of the dominant classes
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Solvent Free Synthesis of α,α-Bis(Substituted-benzylidene)cycloalkanones Using Covalently Anchored Sulfonic Acid on Silica Gel(SiO_(2)-R-SO_(3)H)as an Efficient and Reusable Heterogeneous Catalyst
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作者 Azizollah Habibi Enayatollah Sheikhhosseini +2 位作者 Mohammadali Bigdeli Saeed Balalaie Elinaz Farrokhi 《International Journal of Organic Chemistry》 2011年第4期143-147,共5页
We wish to report a mild and efficient Crossed-Aldol reaction for the synthesis of α, ?-bis(substituted-ben- zylidene)cycloalkanones in the presence of catalytic amounts of covalently anchored sulfonic acid onto sil-... We wish to report a mild and efficient Crossed-Aldol reaction for the synthesis of α, ?-bis(substituted-ben- zylidene)cycloalkanones in the presence of catalytic amounts of covalently anchored sulfonic acid onto sil- ica gel under heterogeneous and solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure and work up steps, short reaction times and easy recovery of the catalyst. We have also demonstrated that the catalyst can be reused successfully. 展开更多
关键词 Crossed-Aldol Condensation Heterogeneous Catalysis α α-bis(substituted-benzylidene)cycloalkanones SiO_(2)-R-SO_(3)H Solvent-Free
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One-pot synthesis of 2,5-bis(hydroxymethyl)furan from biomass derived 5-(chloromethyl)furfural in high yield 被引量:1
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作者 Binglin Chen Yunchao Feng +9 位作者 Sen Ma Weizhen Xie Guihua Yan Zheng Li Jonathan Sperry Shuliang Yang Xing Tang Yong Sun Lu Lin Xianhai Zeng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期421-428,I0011,共9页
5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated... 5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated for the first time.A 91%BHMF yield was obtained over Ru/Cu Oxcatalyst,and BHMF was mainly produced by the consecutive hydrolysis and hydrogenation of CMF with 5-hydroxymethylfurfural(HMF)as an intermediate.Kinetic studies revealed that the conversion of HMF to BHMF was the rate-determining step.Remarkably,the characterizations and density functional theory(DFT)calculations further revealed the lower electron density of Ru NPs in Ru/Cu Oxcatalyst,resulting in a larger adsorption energy and a smaller free energy difference for the formation of alcohols.The present findings offered a new pathway for biomass-derived diol production through CMF as a potential source. 展开更多
关键词 2 5-bis(hydroxymethyl)furan Hydrolysis Hydrogenation Biomass conversion Heterogeneous catalysis
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Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil 被引量:1
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作者 Minghui Cao Yan Duan +6 位作者 Minghao Li Caiguo Tang Wenjie Kan Jiangye Li Huilan Zhang Wenling Zhong Lifang Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期698-710,共13页
Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidif... Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity reduction.Meanwhile,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity benefits.However,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain uncertain.To bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure application.All fertilization treatments were designed to have equal N input.Our results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with CF.SOC,AP,and the soil C:N ratio were mainly responsible for microbial community variations.The co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,respectively.These specific taxa are implicated in soil macroelement turnover.Random Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop yield.The present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies. 展开更多
关键词 FERTILIZATION manure substitution soil fertility maize yield bacterial community
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Investigation of the Nd-Ce-Mg-Zn/Substituted Hydroxyapatite Effect on Biological Properties and Osteosarcoma Cells
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作者 Suha Q.AL-Shahrabalee Hussein Alaa Jaber 《Journal of Renewable Materials》 SCIE EI 2023年第3期1485-1498,共14页
Cancerous diseases and diseases resulting from bacteria and fungi are some of the pressures that humans face.Therefore,the development of biomaterials that are resistant to cancerous diseases,bacteria,and fungi has be... Cancerous diseases and diseases resulting from bacteria and fungi are some of the pressures that humans face.Therefore,the development of biomaterials that are resistant to cancerous diseases,bacteria,and fungi has become one of the requirements of the medical field to extend the life of the biomaterial and fight pathogens after implanting these materials inside the human body.One of the important biomaterials used in the field of orthopedics is hydroxyapatite.In this research,Nano substituted hydroxyapatite was prepared by the wet precipitation method,including replacing 5%of the calcium ions with neodymium,cerium,magnesium,and zinc ions in cationic substitution.Many tests were carried out to characterize the prepared material.The biological properties were evaluated by examining the resistance of the substituted hydroxyapatite to bacteria and fungi,in addition to testing the effect of the material on normal cells and bone cancer cells.The results showed a new structure of hydroxyapatite after the substitution process and a significant improvement in the biological properties of the prepared biomaterial compared to other researches. 展开更多
关键词 HYDROXYAPATITE NEODYMIUM CERIUM substitutION
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Fate of Parent and Substituted Polycyclic Aromatic Hydrocarbons in SBR/MBBR Treatment Process:Experimental Value Against Model Prediction
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作者 ZHAO Jing TIAN Weijun +3 位作者 LIU Shuhui QIAO Kaili DU Zhaoyang XIE Wenlong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第2期479-489,共11页
The knowledge of the existence,distribution and fate of polycyclic aromatic hydrocarbons(PAHs)and substituted polycyclic aromatic hydrocarbons(SPAHs)in wastewater treatment plants(WWTPs)was vital for reducing their co... The knowledge of the existence,distribution and fate of polycyclic aromatic hydrocarbons(PAHs)and substituted polycyclic aromatic hydrocarbons(SPAHs)in wastewater treatment plants(WWTPs)was vital for reducing their concentrations entering the aquatic environment.The concentrations of 13 SPAHs and 16 PAHs were all determined in a WWTP with styrene butadiene rubber(SBR)in partnership with the moving bed biofilm reactor(MBBR)process.SPAHs presented a higher concentration lever than PAHs in nearly all samples.The total removal efficiencies of PAHs and SPAHs ranged from 64.0%to 71.36%and 78.4%to 79.7%,respectively.The total yearly loads of PAHs(43.0 kg)and SPAHs(73.0 kg)were mainly reduced by the primary and SBR/MBBR biological treatment stages.The tertiary treatment stage had a minor contribution to target compounds removal.According to a synthesis and improvement fate model,we found that the dominant processes changed as the chemical octanol water partition coefficient(K_(ow))increased.But the seasonal variations of experimental removal efficiencies were more obvious than that of predicted data.In the primary sedimentation tank,dissolution in the aqueous phase and sorption to sludge/particulate matter were controlling processes for the removal of PAHs and SPAHs.The sorption to sludge and biodegradation were the principal removal mechanisms during the SBR/MBBR biological treatment process.The contribution of volatilization to removal was always insignificant.Furthermore,the basic physicochemical properties and operating parameters influenced the fate of PAHs and SPAHs in the WWTP. 展开更多
关键词 substituted polycyclic aromatic hydrocarbons moving bed biofilm reactor removal efficiency fate process model
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Effect of Rare-Earth Element Substitution in Superconducting R_(3)Ni_(2)O_(7) under Pressure
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作者 Zhiming Pan Chen Lu +1 位作者 Fan Yang Congjun Wu 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期77-81,共5页
Recently,high temperature(T_(c)≈80 K)superconductivity(SC)has been discovered in La_(3)Ni_(2)O_(7)(LNO)under pressure.This raises the question of whether the superconducting transition temperature T_(c) could be furt... Recently,high temperature(T_(c)≈80 K)superconductivity(SC)has been discovered in La_(3)Ni_(2)O_(7)(LNO)under pressure.This raises the question of whether the superconducting transition temperature T_(c) could be further enhanced under suitable conditions.One possible route for achieving higher T_(c) is element substitution.Similar SC could appear in the Fmmm phase of rare-earth(RE)R_(3)Ni_(2)O_(7)(RNO,R=RE element)material series under suitable pressure.The electronic properties in the RNO materials are dominated by the Ni 3d orbitals in the bilayer NiO_(2) plane.In the strong coupling limit,the SC could be fully characterized by a bilayer single 3d_(x^(2)−y^(2))-orbital t–J‖–J⊥ model.With RE element substitution from La to other RE element,the lattice constant of the Fmmm RNO material decreases,and the resultant electronic hopping integral increases,leading to stronger superexchanges between the 3d_(x^(2)−y^(2)) orbitals.Based on the slave-boson mean-field theory,we explore the pairing nature and the evolution of T_(c) in RNO materials under pressure.Consequently,it is found that the element substitution does not alter the pairing nature,i.e.,the inter-layer s-wave pairing is always favored in the superconducting RNO under pressure.However,the T_(c) increases from La to Sm,and a nearly doubled T_(c) could be realized in SmNO under pressure.This work provides evidence for possible higher T_(c) R_(3)Ni_(2)O_(7) materials,which may be realized in further experiments. 展开更多
关键词 ELEMENT substitutION RARE
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Atom substitution of the solid-state electrolyte Li_(10)GeP_(2)S_(12)for stabilized all-solid-state lithium metal batteries
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作者 Zijing Wan Xiaozhen Chen +3 位作者 Ziqi Zhou Xiaoliang Zhong Xiaobing Luo Dongwei Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期28-38,I0002,共12页
Solid-state electrolyte Li_(10)GeP_(2)S_(12)(LGPS)has a high lithium ion conductivity of 12 mS cm^(-1)at room temperature,but its inferior chemical stability against lithium metal anode impedes its practical applicati... Solid-state electrolyte Li_(10)GeP_(2)S_(12)(LGPS)has a high lithium ion conductivity of 12 mS cm^(-1)at room temperature,but its inferior chemical stability against lithium metal anode impedes its practical application.Among all solutions,Ge atom substitution of the solid-state electrolyte LGPS stands out as the most promising solution to this interface problem.A systematic screening framework for Ge atom substitution including ionic conductivity,thermodynamic stability,electronic and mechanical properties is utilized to solve it.For fast screening,an enhanced model Dop Net FC using chemical formulas for the dataset is adopted to predict ionic conductivity.Finally,Li_(10)SrP_(2)S_(12)(LSrPS)is screened out,which has high lithium ion conductivity(12.58 mS cm^(-1)).In addition,an enhanced migration of lithium ion across the LSr PS/Li interface is found.Meanwhile,compared to the LGPS/Li interface,LSrPS/Li interface exhibits a larger Schottky barrier(0.134 eV),smaller electron transfer region(3.103?),and enhanced ability to block additional electrons,all of which contribute to the stabilized interface.The applied theoretical atom substitution screening framework with the aid of machine learning can be extended to rapid determination of modified specific material schemes. 展开更多
关键词 Atom substitution Solid-state electrolyte Machine learning Stabilized interface
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Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution
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作者 Xuan Wang Akang Chen +3 位作者 XinLei Wu Jiatao Zhang Jichen Dong Leining Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期49-94,共46页
In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterpart... In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterparts.The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications.In this context,the atomic substitution method has emerged as a favorable approach.It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting materials.In this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC materials.The effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are discussed.The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these advancements.Finally,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized. 展开更多
关键词 Transition metal chalcogenides Atomic substitution Ion exchange Low-dimensional materials Controllable synthesis
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Yolk free egg substitute improves the serum phospholipid profile of mice with metabolic syndrome based on lipidomic analysis
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作者 Zhihui Yu Lingyu Fan +3 位作者 Fei Tai Lixin Zhang Xiaoyu Zhang Yisheng Chen 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期482-493,共12页
In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with wh... In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with whole egg group(WE),HFD with free-yolk egg substitute group(YFES),and HFD with lovastatin group(Lov).Main biochemical indexes and a non-targeted lipidomic analysis were employed to insight the lipid profile changes in serum.It was revealed that WE could significantly improve serum biochemical indexes by reducing body weight,low-density lipoprotein cholesterol(LDL-C)and total cholesterol(TC),while increasing high-density lipoprotein cholesterol.YFES exhibited remarkably better performance in increasing phosphatidylglycerol and phosphatidic acids,while decreasing phosphatidylinositol than WE.A total of 50 differential lipids biomarkers tightly related to glycerophospholipids metabolism were screened out.Carnitine C18:2 and C12:1,SM(d18:0/12:0),and SM(d18:1/14:1)were significantly upregulated in YFES compared to WE.YFES reduced expression of SREBP-1c and Cpt1a,while did not affect the expression of PPAR-α.Sphingomyelin biomarkers were positively related to the TC(|r|>0.6),while PPAR-αwas negatively correlated with triglyceride and LDL-C levels.To sum up,YFES attenuated HFD-induced Met S by improving the serum phospholipids,which account for its modulation of glycerophospholipid metabolism. 展开更多
关键词 Metabolic syndrome Whole egg Yolk free egg substitute SERUM LIPIDOMICS
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Atomically Substitutional Engineering of Transition Metal Dichalcogenide Layers for Enhancing Tailored Properties and Superior Applications
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作者 Zhaosu Liu Si Yin Tee +1 位作者 Guijian Guan Ming‑Yong Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期248-284,共37页
Transition metal dichalcogenides(TMDs)are a promising class of layered materials in the post-graphene era,with extensive research attention due to their diverse alternative elements and fascinating semiconductor behav... Transition metal dichalcogenides(TMDs)are a promising class of layered materials in the post-graphene era,with extensive research attention due to their diverse alternative elements and fascinating semiconductor behavior.Binary MX2 layers with different metal and/or chalcogen elements have similar structural parameters but varied optoelectronic properties,providing opportunities for atomically substitutional engineering via partial alteration of metal or/and chalcogenide atoms to produce ternary or quaternary TMDs.The resulting multinary TMD layers still maintain structural integrity and homogeneity while achieving tunable(opto)electronic properties across a full range of composition with arbitrary ratios of introduced metal or chalcogen to original counterparts(0–100%).Atomic substitution in TMD layers offers new adjustable degrees of freedom for tailoring crystal phase,band alignment/structure,carrier density,and surface reactive activity,enabling novel and promising applications.This review comprehensively elaborates on atomically substitutional engineering in TMD layers,including theoretical foundations,synthetic strategies,tailored properties,and superior applications.The emerging type of ternary TMDs,Janus TMDs,is presented specifically to highlight their typical compounds,fabrication methods,and potential applications.Finally,opportunities and challenges for further development of multinary TMDs are envisioned to expedite the evolution of this pivotal field. 展开更多
关键词 Transition metal dichalcogenides Atomic substitution Tailored structure Tunable bandgap Enhanced applications
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Computational Study for the Aromatic Nucleophilic Substitution Reaction on 1-Dimethylamino-2,4-bis(trifluoroacetyl)-naphthalene with Amines
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作者 Norio Ota Tomohiro Nakada +2 位作者 Takumi Shintani Yasuhiro Kamitori Etsuji Okada 《International Journal of Organic Chemistry》 2018年第3期273-281,共9页
Our previous research showed that aliphatic amines were put in order of high reactivity as “ethylamine > ammonia > t-butylamine > diethylamine” on the aromatic nucleophilic substitution of 1-dimetylamino-2,... Our previous research showed that aliphatic amines were put in order of high reactivity as “ethylamine > ammonia > t-butylamine > diethylamine” on the aromatic nucleophilic substitution of 1-dimetylamino-2,4-bis(trifluoroacetyl)-naphthalene 1 in acetonitrile. The DFT calculation study (B3LYP/6-31G* with solvation model) for the reactions of 1 with above four amines rationally explained the difference of each amines reactivity based on the energies of their Meisenheimer complexes 3 which are assumed to formed as the reaction intermediates in the course of the reaction giving the corresponding N-N exchange products 2. Intramolecular hydrogen bond between amino proton in 1-amino group and carbonyl oxygen in 2-trifluoroacetyl group stabilizes Meisenheimer complexes 3 effectively, and accelerates the substitution reaction from 1 to 2. Our calculation results also predicted that the above order of amines is also true if less polar toluene is used as a solvent instead of acetonitrile even though more enhanced conditions are required. 展开更多
关键词 1-Amino-2 4-bis(trifluoroacetyl)naphthalenes Aliphatic AMINES Meisenheimer Complexes AROMATIC NUCLEOPHILIC substitution DFT Calculation
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Design of low-alloying and high-performance solid solution-strengthened copper alloys with element substitution for sustainable development
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作者 Jiaqiang Li Hongtao Zhang +2 位作者 Jingtai Sun Huadong Fu Jianxin Xie 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期826-832,共7页
Solid solution-strengthened copper alloys have the advantages of a simple composition and manufacturing process,high mechanical and electrical comprehensive performances,and low cost;thus,they are widely used in high-... Solid solution-strengthened copper alloys have the advantages of a simple composition and manufacturing process,high mechanical and electrical comprehensive performances,and low cost;thus,they are widely used in high-speed rail contact wires,electronic component connectors,and other devices.Overcoming the contradiction between low alloying and high performance is an important challenge in the development of solid solution-strengthened copper alloys.Taking the typical solid solution-strengthened alloy Cu-4Zn-1Sn as the research object,we proposed using the element In to replace Zn and Sn to achieve low alloying in this work.Two new alloys,Cu-1.5Zn-1Sn-0.4In and Cu-1.5Zn-0.9Sn-0.6In,were designed and prepared.The total weight percentage content of alloying elements decreased by 43%and 41%,respectively,while the product of ultimate tensile strength(UTS)and electrical conductivity(EC)of the annealed state increased by 14%and 15%.After cold rolling with a 90%reduction,the UTS of the two new alloys reached 576 and 627MPa,respectively,the EC was 44.9%IACS and 42.0%IACS,and the product of UTS and EC(UTS×EC)was 97%and 99%higher than that of the annealed state alloy.The dislocations proliferated greatly in cold-rolled alloys,and the strengthening effects of dislocations reached 332 and 356 MPa,respectively,which is the main reason for the considerable improvement in mechanical properties. 展开更多
关键词 element substitution copper alloy solid solution strengthening microstructure and performance
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Atomic Ni directional-substitution on ZnIn_(2)S_(4) nanosheet to achieve the equilibrium of elevated redox capacity and efficient carrier-kinetics performance in photocatalysis
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作者 Haibin Huang Guiyang Yu +5 位作者 Xingze Zhao Boce Cui Jinshi Yu Chenyang Zhao Heyuan Liu Xiyou Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期272-281,I0007,共11页
It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced ... It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced into the lattice of hexagonal ZnIn_(2)S_(4) nanosheets(Ni/ZnIn_(2)S_(4))via directionalsubstituting Zn atom with the facile hydrothermal method.The electronic structure calculations indicate that the introduction of Ni atom effectively extracts more electrons and acts as active site for subsequent reduction reaction.Besides the optimized light absorption range,the elevation of Efand ECBendows Ni/ZnIn_(2)S_(4) photocatalyst with the increased electron concentration and the enhanced reduction ability for surface reaction.Moreover,ultrafast transient absorption spectroscopy,as well as a series of electrochemical tests,demonstrates that Ni/ZnIn_(2)S_(4) possesses 2.15 times longer lifetime of the excited charge carriers and an order of magnitude increase for carrier mobility and separation efficiency compared with pristine ZnIn_(2)S_(4).These efficient kinetics performances of charge carriers and enhanced redox capacity synergistically boost photocatalytic activity,in which a 3-times higher conversion efficiency of nitrobenzene reduction was achieved upon Ni/ZnIn_(2)S_(4).Our study not only provides in-depth insights into the effect of atomic directional-substitution on the kinetic behavior of photogenerated charges,but also opens an avenue to the synchronous optimization of redox capacity and carrier-kinetics performance for efficient solar energy conversion. 展开更多
关键词 ZnIn_(2)S_(4) substitutION Carrier kinetics Redox capacity PHOTOCATALYSIS
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Effects of long-term partial substitution of inorganic fertilizer with pig manure and/or straw on nitrogen fractions and microbiological properties in greenhouse vegetable soils
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作者 Shuo Yuan Ruonan Li +5 位作者 Yinjie Zhang Hao'an Luan Jiwei Tang Liying Wang Hongjie Ji Shaowen Huang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2083-2098,共16页
Partial substitution of inorganic fertilizers with organic amendments is an important agricultural management practice.An 11-year field experiment(22 cropping periods)was carried out to analyze the impacts of differen... Partial substitution of inorganic fertilizers with organic amendments is an important agricultural management practice.An 11-year field experiment(22 cropping periods)was carried out to analyze the impacts of different partial substitution treatments on crop yields and the transformation of nitrogen fractions in greenhouse vegetable soil.Four treatments with equal N,P_(2)O_(5),and K_(2)O inputs were selected,including complete inorganic fertilizer N(CN),50%inorganic fertilizer N plus 50%pig manure N(CPN),50%inorganic fertilizer N plus 25%pig manure N and 25%corn straw N(CPSN),and 50%inorganic fertilizer N plus 50%corn straw N(CSN).Organic substitution treatments tended to increase crop yields since the 6th cropping period compared to the CN treatment.From the 8th to the 22nd cropping periods,the highest yields were observed in the CPSN treatment where yields were 7.5-11.1%greater than in CN treatment.After 11-year fertilization,compared to CN,organic substitution treatments significantly increased the concentrations of NO_(3)^(-)-N,NH_(4)^(+)-N,acid hydrolysis ammonium-N(AHAN),amino acid-N(AAN),amino sugar-N(ASN),and acid hydrolysis unknown-N(AHUN)in soil by 45.0-69.4,32.8-58.1,49.3-66.6,62.0-69.5,34.5-100.3,and 109.2-172.9%,respectively.Redundancy analysis indicated that soil C/N and OC concentration significantly affected the distribution of N fractions.The highest concentrations of NO_(3)^(-)-N,AHAN,AAN,AHUN were found in the CPSN treatment.Organic substitution treatments increased the activities ofβ-glucosidase,β-cellobiosidase,N-acetyl-glucosamidase,L-aminopeptidase,and phosphatase in the soil.Organic substitution treatments reduced vector length and increased vector angle,indicating alleviation of constraints of C and N on soil microorganisms.Organic substitution treatments increased the total concentrations of phospholipid fatty acids(PLFAs)in the soil by 109.9-205.3%,and increased the relative abundance of G^(+)bacteria and fungi taxa,but decreased the relative abundance of G-bacteria,total bacteria,and actinomycetes.Overall,long-term organic substitution management increased soil OC concentration,C/N,and the microbial population,the latter in turn positively influenced soil enzyme activity.Enhanced microorganism numbers and enzyme activity enhanced soil N sequestration by transforming inorganic N to acid hydrolysis-N(AHN),and enhanced soil N supply capacity by activating non-acid hydrolysis-N(NAHN)to AHN,thus improving vegetable yield.Application of inorganic fertilizer,manure,and straw was a more effective fertilization model for achieving sustainable greenhouse vegetable production than application of inorganic fertilizer alone. 展开更多
关键词 organic substitution management greenhouse vegetable production N fractions microbial community composition extracellular enzyme activity enzyme stoichiometry coefficients
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Syntheses and Olfactory Characters of Some Endo-α-Substituted-Bicyclo[2. 2. 2]-Octenyl (or Octanyl) Methanols
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作者 TANG Shi-xiong , CAO Yu-rong, WANG Xiu-ling, XUE Jie-you, WANG Xiao-lan (Department of Chemistry, Nankai University, Tianjin, 300071) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第3期219-223,共5页
Sixteen title compounds were synthesized, twelve of which are new ones. Their structures were determined by 1H NMR, IR and MS, the refractive indices or melting points were measured. Odors of all the title compounds w... Sixteen title compounds were synthesized, twelve of which are new ones. Their structures were determined by 1H NMR, IR and MS, the refractive indices or melting points were measured. Odors of all the title compounds were evaluated and the structure-odor relationship was briefly discussed. 展开更多
关键词 Endo-α-substituted-bicyclo[2. 2. 2] octenyl methanol Synthesis ODOR
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UPLC-MS/MS法测定槲寄生抗肿瘤成分1,7-bis(4-hydroxyphenyl)-1,4-heptadien-3-one的含量 被引量:2
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作者 张照燕 龙猜 +3 位作者 田秀敏 于治国 党晓伟 赵云丽 《沈阳药科大学学报》 CAS CSCD 北大核心 2018年第1期53-57,共5页
目的建立超高效液相色谱-串联质谱法(UPLC/MS/MS)测定槲寄生中具有抗肿瘤活性的新化合物1,7-bis(4-hydroxyphenyl)-1,4-heptadien-3-one(BHPHD)的含量,并通过多因素方差分析比较产地与寄主对药材抗肿瘤成分含量的影响。方法以Thermo Hyp... 目的建立超高效液相色谱-串联质谱法(UPLC/MS/MS)测定槲寄生中具有抗肿瘤活性的新化合物1,7-bis(4-hydroxyphenyl)-1,4-heptadien-3-one(BHPHD)的含量,并通过多因素方差分析比较产地与寄主对药材抗肿瘤成分含量的影响。方法以Thermo Hypersil GOLD C18(50 mm×2.1 mm,1.9μm)为分离色谱柱,乙腈-体积分数0.1%甲酸水溶液为流动相,流速0.2 m L·min-1,梯度洗脱,质谱检测器,电喷雾正离子,多反应监测模式,监测离子对m/z 295.09→106.99。结果BHPHD在质量浓度为0.050~2.5 mg·L-1内线性关系良好,精密度、重复性、稳定性试验的RSD均≤3.5%,平均加样回收率(n=9)为97.2%(RSD=1.6%)。结论该方法可满足定量要求。多因素方差分析表明槲寄生中BHPHD的含量受产地影响较大(P<0.01),受寄主影响不大。 展开更多
关键词 槲寄生 1 7-bis(4-hydroxyphenyl)-1 4-heptadien-3-one 超高效液相色谱-串联质谱 含量测定
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