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Green and mild synthesis of Ca-MOF/COF functionalized silica microspheres in an acid-base tunable deep eutectic solvent for multi-mode chromatography
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作者 Yuanfei Liu Wanjiao Wei +5 位作者 Xu Liu Rui Hua Yanjuan Liu Yuefei Zhang Wei Chen Sheng Tang 《Chinese Chemical Letters》 2026年第1期547-551,共5页
Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through... Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through covalent bonds exhibits excellent structural stability.It has been shown that the stationary phases prepared by combining MOF and COF can make up for the poor stability of MOF@SiO_(2),and the MOF/COF composites have superior chromatographic separation performance.However,the traditional methods for preparing COF/MOF based stationary phases are generally solvent thermal synthesis.In this study,a green and low-cost synthesis method was proposed for the preparation of MOF/COF@SiO_(2) stationary phase.Firstly,COF@SiO_(2) was prepared in a choline chloride/ethylene glycol based deep eutectic solvent(DES).Secondly,another acid-base tunable DES prepared by mixing p-toluenesulfonic acid(PTSA)and 2-methylimidazole in different proportions was introduced as the reaction solvent and reactant for rapid synthesis of MOF/COF@SiO_(2).Compared with the toxic transition metal-based MOFs selected in most previous studies,a lightweight and non-toxic S-zone metal(calcium) based MOF was employed in this study.PTSA and calcium will form the calcium/oxygen-containing organic acid framework in acidic DES,which assembles with terephthalic acid dissolved in basic DES to form MOF.The strong hydrogen bonding effect of DES can facilitate rapid assembly of Ca-MOF.The obtained Ca-MOF/COF@SiO_(2) can be used for multi-mode chromatography to efficiently separate multiple isomeric/hydrophilic/hydrophobic analytes.The synthesis method of Ca-MOF/COF@SiO_(2) is green and mild,especially the use of acid-base tunable DES promotes the rapid synthesis of non-toxic Ca-MOF/COF@silica composites,which offers an innovative approach of greenly synthesizing novel MOF/COF stationary phases and extends their applications in the field of chromatography. 展开更多
关键词 Metal organic framework Covalent organic framework Deep eutectic solvent Silica composites Multi-mode chromatography
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Synergistic fluorinated and non-fluorinated solvents for electrolytes of lithium-ion batteries at low temperatures
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作者 Xuning Gao Nan Piao +7 位作者 Yukun Yan Jinghao Wang Haolun Zou Siqi Guan Leiying Zeng Zhenhua Sun Guangjian Hu Feng Li 《Chinese Chemical Letters》 2026年第2期582-587,共6页
Commercial carbonate electrolytes suffer from ion transport difficulty in bulk electrolytes and interphase at low temperatures,bringing challenges to the application of lithium-ion batteries(LIBs)at low temperatures.H... Commercial carbonate electrolytes suffer from ion transport difficulty in bulk electrolytes and interphase at low temperatures,bringing challenges to the application of lithium-ion batteries(LIBs)at low temperatures.Herein,the ester solvent of methyl propionate(MP)with low melting point and low viscosity was used to tackle ion transport difficulty in electrolytes.Fluorinated ester was further added to accelerate interfacial transport through intermolecular interactions.The influence of fluorinated esters with different fluorination degrees on the solvation structure of electrolytes and the performance of batteries was further studied.As a result,methyl pentafluoropropionate(M5F)with five fluorine atoms was selected for its optimal interactions with both Li+and MP solvent in the primary solvation structure,contributing to desired solvation structure for fast interfacial transport.The LiFePO4(LFP)||graphite cell with LiFSI-MP-M5F electrolyte exhibited a high cyclability of 85.8%after 120 cycles and retained 81.2%of room-temperature capacity when charged and discharged at−30℃.1 Ah LFP||graphite pouch cell with high cathode loading(20 mg/cm^(2))in LiFSI-MP-M5F electrolyte exhibited 0.85 Ah capacity when charged and discharged at−20℃.This work provides a guidance for electrolyte design by synergistic fluorinated and non-fluorinated solvents for LIBs at low-temperature application. 展开更多
关键词 Lithium-ion batteries ELECTROLYTE Fluorinated solvent Non-fluorinated solvent Solvation structure Low temperatures
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Synthesis and crystal structures of Co(Ⅱ)/Cu(Ⅱ)coordination polymers based on solvent and ligand concentration regulation strategy
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作者 SUN Yinxia LIU Liping +7 位作者 BAI Xue SUN Yu SUN Wanhong DENG Zhepeng CHEN Jianghai WANG Jianjun XU Li ZHANG Shuzhen 《无机化学学报》 北大核心 2026年第2期340-354,共15页
Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2... Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2)O(1)was synthesized as a 2D structure using Coas the metal source,methanol‑water(4∶6,V/V)as the solvent,and specific concentrations of 2,5‑furandicarboxylic acid(H_(2)FDCA)and 1,3,5‑triimidazole benzene(L).Adjusting to pure water and lowering the concentration of L yielded the 1D chain structure of[Co(HL)2(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(2).Using Cu(Ⅱ)as the metal source,methanol/water(9∶1,V/V)as the solvent,and specific concentrations of L and H2FDCA,the 1D chain structure of[Cu(L)(FDCA)(H_(2)O)]·2H_(2)O(3)was synthesized.Upon increasing the concentrations of L and H2FDCA,and switching the solvent to pure water,the 1D chain structure of[Cu(HL)_(2)(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(4)was obtained.This shows that changing the solvent and ligand concentrations can affect the structural changes of CPs.In addition,the solid‑state photoluminescence of CPs 1‑4 at room temperature was studied,and their morphological changes were observed via scanning electron microscopy.Density functional theory calculations revealed that the negative charge concentrates on the O and N atoms of the ligand,facilitating ligand‑metal ion coordination.CCDC:2403934,1;2403935,2;2403936,3;2403938,4. 展开更多
关键词 Co(Ⅱ)/Cu(Ⅱ)coordination polymer crystal structure solvent system ligand concentration regulation strategy
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A Promising Strategy for Solvent-Regulated Selective Hydrogenation of 5-Hydroxymethylfurfural over Porous Carbon-Supported Ni-ZnO Nanoparticles
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作者 Rulu Huang Chao Liu +4 位作者 Kaili Zhang Jianchun Jiang Ziqi Tian Yongming Chai Kui Wang 《Nano-Micro Letters》 2026年第1期130-143,共14页
Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via lo... Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions. 展开更多
关键词 Porous carbon-supported Ni-ZnO nanoparticles catalyst Selective hydrogenation 5-HYDROXYMETHYLFURFURAL solvent Proton-donating ability
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Chemical composition and biological activities of Panax notoginseng
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作者 Yu Wang Da Teng +4 位作者 Zixuan Che Ran Guo Meng Zhang Ying Li Yu Chen 《Asian Journal of Traditional Medicines》 2026年第1期31-41,共11页
Panax notoginseng(P.notoginseng),a valuable traditional Chinese medicine,is the dried root of plants in Acanthopanax gracilistylus family,with the effect of dispersing blood stasis,eliminating swelling and relieving p... Panax notoginseng(P.notoginseng),a valuable traditional Chinese medicine,is the dried root of plants in Acanthopanax gracilistylus family,with the effect of dispersing blood stasis,eliminating swelling and relieving pain.With the development of modern medicine,the active ingredients and mechanisms of P.notoginseng have been gradually revealed.The present paper systematically reviews the chemical composition and biological activities of P.nologinseng,to provide a scientific basis and reference for detailed research on P.nologinseng. 展开更多
关键词 Panax notoginseng chemical composition biological activity
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Geopolymers for stabilizing soils with diverse compositions
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作者 Peng ZHOU Heyuan WANG +3 位作者 Changjie XU Tao FANG Guoliang MA Hanlong LIU 《Science China(Technological Sciences)》 2026年第3期294-307,共14页
One of the research hotspots in geotechnical engineering is the solidification of problematic soil foundations. However, the traditional materials, such as Portland cement, lime, and various types of chemical solution... One of the research hotspots in geotechnical engineering is the solidification of problematic soil foundations. However, the traditional materials, such as Portland cement, lime, and various types of chemical solutions, typically cause CO_(2) emissions and environmental pollution. Geopolymer is a newly proposed method for soil solidification, offering an environmentally friendly and effective solution. Given that soils typically consist of diverse compositions, an optimal soil stabilization technique should be versatile enough to be applied across various soil types, ensuring consistent strength outcomes with minimal variations among different soil compositions. In this study, three commonly used geopolymers(fly ash, ground granulated blast-furnace slag, and metakaolin) were utilized to stabilize silt, loess, silica sand, calcareous sand, and gravel, representing a diverse range of soils. The mechanical properties and microstructures of both geopolymers and geopolymerstabilized soils were analyzed. The findings indicated that the strength of stabilized coarse cohesionless soils was primarily influenced by the mechanical properties of the geopolymers themselves, with minimal impact from the inherent properties of the soil. However, the effectiveness of stabilizing cohesive soil may show significant discrepancies compared to the mechanical properties of geopolymer materials when certain types of geopolymers, like metakaolin, are employed. Higher strength is typically achieved through a denser structure(with fewer pores) and the presence of products with a higher degree of polymerization. Additionally, ground granulated blast-furnace slag exhibited excellent stability and superior strength when compared to other types of geopolymers. The present research establishes a basis for selecting geopolymers to stabilize a range of soils, including those with non-uniform compositions and diverse components. 展开更多
关键词 soil stabilization GEOPOLYMER soils with diverse compositions STRENGTH MICROSTRUCTURE
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Pore pressure evolution and entrainment mechanism of convex unsaturated colluvial beds with divergent compositions under debris flow overriding
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作者 Pu Li Kaiheng Hu Jiading Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期278-298,共21页
A debris flow descending through an erodible convex colluvial bed,originating from a landslide dam and its upstream deposits,can entrain massive amounts of sediment,dramatically increasing the debris flow volume.Most ... A debris flow descending through an erodible convex colluvial bed,originating from a landslide dam and its upstream deposits,can entrain massive amounts of sediment,dramatically increasing the debris flow volume.Most existing erosion models assume that bed sediments are fully saturated,although this condition is rarely observed in nature.Therefore,a thorough understanding of debris flow overtopping erosion on a convex unsaturated bed is crucial for quantifying disaster risk.In this study,we experimentally investigated the effects of sediment composition,specifically coarse-grain size distribution and fine particle content,on the pore pressure evolution and entrainment of debris flows overriding a convex unsaturated colluvial bed.The average entrainment rate at convex sites for continuously graded bed sediment was higher than its discontinuous counterpart.The measured pore pressures within the unsaturated bed sediments were primarily generated by the passing debris flows.Furthermore,it was found that these pressures decreased as the fine particle content increased and the coarse-grain size of the erodible substrates decreased.When the coarse-grain size of the debris flow was smaller than that of the bed sediment,only a portion of the eroded material was entrained by the moving debris flow.In contrast,when the coarse-grain size of the debris flow was equal to or greater than that of the bed sediment,nearly all of the eroded material was entrained.The findings of this study could contribute to the assessment of hazard amplification and inform the design of mitigation and prevention strategies. 展开更多
关键词 Debris flow Convex colluvial bed Sediment composition Unsaturated bed Pore pressure ENTRAINMENT
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CONTROLLING THE SURFACE COMPOSITION OF PCBM IN P3HT/PCBM BLEND FILMS BY USING MIXED SOLVENTS WITH DIFFERENT EVAPORATION RATES 被引量:4
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作者 Yue Sun Jian-gang Liu +1 位作者 Yan Ding 韩艳春 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第7期1029-1037,共9页
The surface composition of poly(3-hexylthiophene-2,5-diyl) and fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (P3HT/PCBM) blend films could be changed by controlling the film formation process via... The surface composition of poly(3-hexylthiophene-2,5-diyl) and fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (P3HT/PCBM) blend films could be changed by controlling the film formation process via using mixed solvents with different evaporation rates. The second solvent, with a higher boiling point than that of the first solvent and much better solubility for PCBM than P3HT, is chosen to mix with the first solvent with a lower boiling point and good solubility for both PCBM and P3HT. The slow evaporation rate of the second solvent provides enough time for PCBM to diffuse upwards during the solvent evaporation. Thus, the weight ratio of PCBM and P3HT (mpcBM/mp3HT) at surface of the blend films was varied from ca. 0.1 to ca. 0.72, i.e., it increases about seven times by changing from single solvent to mixed solvents. Meanwhile, the mixed solvents were in favor to form P3HT naonofiber network and enhance phase separation of P3HT/PCBM blend films. As a result, the power conversion efficiency of the device from mixed solvents with slow evaporation process was about 1.5 times of the one from single solvents. 展开更多
关键词 P3HT PCBM Surface composition Mixed solvents Slow evaporation.
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Oxidative desulfurization of diesel fuel with caprolactam-based acidic deep eutectic solvents: Tailoring the reactivity of DESs by adjusting the composition 被引量:13
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作者 LingwanHao TingSu +3 位作者 DongmeiHao ChangliangDeng WanzhongRen HongyingLü 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第9期1552-1559,共8页
Despite the significance of hydrogen bonding in deep eutectic solvents(DESs) for desulfurization processes, little is understood about the relationship between the DES composition, hydrogen-bonding strength, and oxi... Despite the significance of hydrogen bonding in deep eutectic solvents(DESs) for desulfurization processes, little is understood about the relationship between the DES composition, hydrogen-bonding strength, and oxidative desulfurization activity. In this study, a new family of caprolactam-based acidic DESs was prepared with different molar ratios of caprolactam and oxalic acid. The prepared DESs were characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, 1 H nuclear magnetic resonance, and thermogravimetric analyses. These DESs were employed for oxidative desulfurization reactions and the desulfurization efficiency was found to vary regularly with the DES composition. The factors influencing the removal of dibenzothiophene were systematically investigated and the desulfurization efficiency of the caprolactam-based acidic DESs reached as high as 98% under optimal conditions. The removal of different sulfur compounds followed the order: dibenzothiophene 4,6-dimethyldibenzothiophene benzothiophene. The combined experimental data and characterization results revealed that the oxidative desulfurization efficiency of the system was influenced by the hydrogen bonding interactions with the DES, which can be optimized by adjusting the DES composition. These findings regarding hydrogen bonding in DESs provide new insight for better understanding of the mechanism of diesel deep desulfurization processes. 展开更多
关键词 Acidic deepeutectic solvents Diesel DIBENZOTHIOPHENE HYDROGENBOND Oxidativede sulfurization
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Molar volume of eutectic solvents as a function of molar composition and temperature 被引量:1
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作者 Farouq S.Mjalli 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第12期1779-1785,共7页
The conventional Rackett model for predicting liquid molar volume has been modified to cater for the effect of molar composition of the Deep Eutectic Solvents(DES). The experimental molar volume data for a group of co... The conventional Rackett model for predicting liquid molar volume has been modified to cater for the effect of molar composition of the Deep Eutectic Solvents(DES). The experimental molar volume data for a group of commonly used DES has been used for optimizing the improved model. The data involved different molar compositions of each DES. The validation of the new model was performed on another set of DESs. The average relative deviation of the model on the training and validation datasets was approximately 0.1% while the Rackett model gave a relative deviation of more than 1.6%. The modified model deals with variations in DES molar composition and temperature in a more consistent way than the original Rackett model which exhibits monotonic performance degradation as temperature moves away from reference conditions. Having the composition of the DES as a model variable enhances the practical utilization of the predicting model in diverse design and process simulation applications. 展开更多
关键词 Molar volume Density Physical properties Ionic liquids Eutectic solvents
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EFFECTS OF SOLVENT TREATMENT ON SURFACE MORPHOLOGY AND COMPOSITION OF POLY(METHYL METHACRYLATE)-g-POLY(ETHYLENE OXIDE)
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作者 郭圣荣 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第4期405-412,共8页
Surface morphology and composition of solution-cast films of poly(methyl methacrylate)-g-poly(ethylene oxide)(PMMA-g-PEO) were investigated by using XPS, DSC, SEM and contact angle measurement. The microphase separate... Surface morphology and composition of solution-cast films of poly(methyl methacrylate)-g-poly(ethylene oxide)(PMMA-g-PEO) were investigated by using XPS, DSC, SEM and contact angle measurement. The microphase separatedstructure of the copolymers was studied by TEM. Generally, for the same graft copolymer, the surface content of PEO orhydrophilicity can be as follows: Surface treated with petroleum ether or cyclohexane>surface untreated with solvent>surface treated with water or ethyl alcohol. Graft copolymer having longer PEO side chains and higher PEO content shows aseparated PEO phase with even a certain degree of crystallinity on the surface. PEO crystallinity was destroyed by water orethyl alcohol treatment, however, surface treatment with petroleum ether or cyclohexane favors the growth of PEO crystal.TEM shows that graft copolymers with longer PEO side chains (M_n of PEO, 3200) may readily undergo microphase separation and the shape and size of domains depend on the copolymer's composition. 展开更多
关键词 PMMA-g-PEO Surface morphology Surface solvent treatment
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EFFECT OF THE COMPOSITION OF m-CRESOL/H_2O SOLVENT ON HYDRODYNAMIC PROPERTIES OF NYLON 6
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作者 Musa Kaleem Baloch Mohsan Nawaz 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第4期369-377,共9页
The intrinsic viscosity [η], Huggins constant (Ku), [η]0, α^3 and flow activation energy values of nylon 6 have been measured in wateηm-cresol (0/100-20/80) systems at different temperatures (20-60℃). It ha... The intrinsic viscosity [η], Huggins constant (Ku), [η]0, α^3 and flow activation energy values of nylon 6 have been measured in wateηm-cresol (0/100-20/80) systems at different temperatures (20-60℃). It has been found that the intrinsic viscosity, [η]0 and α^3 increase with the increase in water contents in m-cresol up to 15% and then decrease. They increase with the increase in temperature irrespective of solvent composition. It has been noted that the percent increase of α^3 is the highest at 60℃ and the lowest at 20℃ for a particular solvent system. The intrinsic viscosity data obey Arrhenius equation over the considered conditions. The activation energy and the KH values decrease very sharply with the addition of water, giving a minimum value at 15% of water and then increase slowly. The variation of all the parameters has been explained in terms of variation in thermodynamic quality of solvent with the addition of water to m-cresol and change in temperature, resulting in the change of conformational and orientational properties of polymer molecules. This change of solvent quality also results in variation of selective sorption of solvent over the polymer, such as hydrogen bonding, etc. 展开更多
关键词 Intrinsic viscosity Huggins constant Thermodynamic quality of solvent Activation energy Hydrogen bonding CONFORMATION Selective sorption.
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Solvent Composition Effect on PDMS Composite Dielectric Elastomer Actuator
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作者 Satoshi Tamura Ryotaro Kiyono Toshihiro Hirai 《Materials Sciences and Applications》 2021年第11期504-518,共15页
Polydimethylsiloxane (PDMS) is inactive to electric fields, but when combined with ferroelectric cyanoethyl sucrose (CR-U), it becomes an electrically active actuator material. The PDMS/CR-U composites were prepared b... Polydimethylsiloxane (PDMS) is inactive to electric fields, but when combined with ferroelectric cyanoethyl sucrose (CR-U), it becomes an electrically active actuator material. The PDMS/CR-U composites were prepared by casting method using tetrahydrofuran (THF) and acetone (ACT) as solvents. The effect of a mixed solvent composition was investigated. The viscosity of the PDMS/CR-U/solvent solution decreased as the THF composition increased. The composite film obtained by evaporation of the solvent and cross-linkage of PDMS showed a phase-separated structure. Spherical CR-U dispersed in the PDMS matrix with a skin layer on one surface side. Electrical resistance, dielectric constant, space-charge distribution, and electrically induced bending deformation behavior were investigated for these composite films. The composite films prepared from a THF-rich solvent exhibited lower surface resistivity than those prepared from a THF-poor solvent. Applying an electric field to the composite film resulted in an asymmetric space-charge distribution with charge accumulation in the skin layer. THF content decreased the viscosity of the solution, meaning the decrease of the apparent size of PDMS chain aggregates. It allows the dispersion of CR-U in the PDMS matrix and also results in the decline of resistivity, the increase of permittivity, and the increase of charge injection. The results explained the structure formation of the composite film and the electric field response as an actuator. A casting solvent of THF content of 87.5 wt% or more is essential for the function of the PDMS/CR-U composite. 展开更多
关键词 Dielectric Actuator Polydimethylsiloxane Composite solvent composition MORPHOLOGY Charge Accumulation
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Effect of Co-solvent and Pressure on the Thermal Decomposition of 2,2′Azobis-(isobutyronitrile) in Supercritical CO_2 被引量:1
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作者 Hong Ping LI Jun LIU +1 位作者 Hai Fei ZHANG Bu Xing HAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第8期713-714,共2页
The thermal decomposition of 2, 2'-azobis (isobutyronitrile) (AIBN) in supercritical CO2 with cosolvent methanol or cyclohexane has been studied by using UV/Vis spectroscopic method at 335.15 K and at 12.0 MPa and... The thermal decomposition of 2, 2'-azobis (isobutyronitrile) (AIBN) in supercritical CO2 with cosolvent methanol or cyclohexane has been studied by using UV/Vis spectroscopic method at 335.15 K and at 12.0 MPa and 14.0 MPa. Both of the cosolvents can accelerate the decomposition rate, and the effect of methanol is more significant than that of the cyclohexane. 展开更多
关键词 Supercritical CO2 CO-solvent 2 2′-Azobis(isobutyronitrile) thermal decomposition pressure effect.
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Quantitative Analysis of the Fatty Acid Compositions of Different Oils and Associations with Antioxidant Capacity and Oxidative Stability 被引量:3
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作者 LIU Junchen SUN Xiaoman +3 位作者 ZHANG Huirong SHAO Haofan LING Xiao LI Li 《现代食品科技》 北大核心 2025年第4期305-315,共11页
Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships w... Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils. 展开更多
关键词 gas chromatography-mass spectrometry vegetable oil fatty acid composition oxidative stability antioxidant capacity
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Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:6
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作者 Long Weimin 《稀有金属材料与工程》 北大核心 2025年第4期837-853,共17页
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ... Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects. 展开更多
关键词 design of brazing filler metals design guidelines for composition Ag based brazing filler metals eutectic structures evolution
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Effect of Nitrocellulose-modified HTPB Binder on the Thermal Decomposition Behavior of Ammonium Nitrate/Magnesium Solid Propellant 被引量:1
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作者 Mohammed Jouini Amir Abdelaziz +4 位作者 Ahmed Fouzi Tarchoun Fateh Chalghoum Yash Pal Weiqiang Pang Djalal Trache 《火炸药学报》 北大核心 2025年第4期372-381,I0004,共11页
An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition b... An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition behavior of a composite propellant(CP)comprising ammonium nitrate(AN)as an oxidizer and magnesium(Mg)as a fuel.Optimization of the propellant formulation was conducted using Chemical Equilibrium with Applications-National Aeronautics and Space Administration(CEA-NASA)software,which demonstrated an increase in specific impulse by 12.09 s when the binder contained 50%NC.Fourier-transform infrared spectroscopy(FTIR)analysis confirmed the excellent compatibility between the components,and density measurements revealed an increase of 6.4%with a higher NC content.Morphological analysis using optical microscopy showed that NC doping improved the uniformity and compactness of the surface,reduced cavities,and achieved a more homogeneous particle distribution.Differential scanning calorimetry(DSC)analysis indicated a decrease in the decomposition temperature of the propellant as the NC content increased,while kinetic studies revealed a 48.68%reduction in the activation energy when 50%NC was incorporated into the binder.These findings suggest that the addition of NC enhances combustion efficiency and improves overall propellant performance.This study highlights the potential of the new HTPB-NC energetic binder as a promising approach for advancing solid propellant technology. 展开更多
关键词 physical chemistry composite propellant HTPB NITROCELLULOSE energetic binder thermal behavior
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Organic solvent nanofiltration membranes for separation in non-polar solvent system 被引量:1
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作者 Shuyun Gu Siyao Li Zhi Xu 《Green Energy & Environment》 2025年第2期244-267,共24页
Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltr... Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltration represents an advanced membrane separation technology capable of discerning molecules within a molecular weight range of approximately 100-1000 Da in organic solvents,offering low energy requirements and minimal carbon footprints.Molecular separation in non-polar solvent system,such as toluene,n-hexane,and n-heptane,has gained paramount importance due to their extensive use in the pharmaceutical,biochemical,and petrochemical industries.In this review,we presented recent advancements in membrane materials,membrane fabrication techniques and their promising applications for separation in nonpolar solvent system,encompassing hydrocarbon separation,bioactive molecule purification and organic solvent recovery.Furthermore,this review highlighted the challenges and opportunities associated with membrane scale-up strategies and the direct translation of this promising technology into industrial applications. 展开更多
关键词 Organic solvent nanofiltration Membranes Membrane separation Non-polar solvent system Petrochemical and pharmaceutical application
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Overcoming low-temperature challenges in LIBs:The role of anion-rich solvation sheath in strong solvents 被引量:2
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作者 Xueqing Min Li Wang +3 位作者 Yanzhou Wu Zhiguo Zhang Hong Xu Xiangming He 《Journal of Energy Chemistry》 2025年第7期63-70,共8页
Lithium-ion batteries(LIBs)face significant limitations in low-temperature environments,with the slow interfacial de-solvation process and the hindered Li+transport through the interphase layer emerging as key obstacl... Lithium-ion batteries(LIBs)face significant limitations in low-temperature environments,with the slow interfacial de-solvation process and the hindered Li+transport through the interphase layer emerging as key obstacles beyond the issue of ionic conductivity.This investigation unveils a novel formulation that constructs an anion-rich solvation sheath within strong solvents,effectively addressing all three of these challenges to bolster low-temperature performance.The developed electrolyte,characterized by an enhanced concentration of contact ion pairs(CIPs)and aggregates(AGGs),facilitates the formation of an inorganic-rich interphase layer on the anode and cathode particles.This promotes de-solvation at low temperatures and stabilizes the electrode-electrolyte interphase.Full cells composed of LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)and graphite,when equipped with this electrolyte,showcase remarkable cycle stability and capacity retention,with 93.3% retention after 500 cycles at room temperature(RT)and 95.5%after 120 cycles at -20℃.This study validates the utility of the anion-rich solvation sheath in strong solvents as a strategy for the development of low-temperature electrolytes. 展开更多
关键词 Electrolytes Solvation structure Low temperature Strong solvents Lithium-ion batteries
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Solvent engineering in perovskite nanocrystal colloid inks for super-fine electrohydrodynamic inkjet printing of color conversion microstructures in micro-LED displays 被引量:2
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作者 Shuli Wang Xuemin Kong +7 位作者 Siting Cai Yunshu Luo Yuxuan Gu Xiaotong Fan Guolong Chen Xiao Yang Zhong Chen Yue Lin 《Chinese Chemical Letters》 2025年第8期554-559,共6页
Super-fine electrohydrodynamic inkjet(SIJ)printing of perovskite nanocrystal(PNC)colloid ink exhibits significant potential in the fabrication of high-resolution color conversion microstructures arrays for fullcolor m... Super-fine electrohydrodynamic inkjet(SIJ)printing of perovskite nanocrystal(PNC)colloid ink exhibits significant potential in the fabrication of high-resolution color conversion microstructures arrays for fullcolor micro-LED displays.However,the impact of solvent on both the printing process and the morphology of SIJ-printed PNC color conversion microstructures remains underexplored.In this study,we prepared samples of CsPbBr3PNC colloid inks in various solvents and investigated the solvent's impact on SIJ printed PNC microstructures.Our findings reveal that the boiling point of the solvent is crucial to the SIJ printing process of PNC colloid inks.Only does the boiling point of the solvent fall in the optimal range,the regular positioned,micron-scaled,conical PNC microstructures can be successfully printed.Below this optimal range,the ink is unable to be ejected from the nozzle;while above this range,irregular positioned microstructures with nanoscale height and coffee-ring-like morphology are produced.Based on these observations,high-resolution color conversion PNC microstructures were effectively prepared using SIJ printing of PNC colloid ink dispersed in dimethylbenzene solvent. 展开更多
关键词 solvent Perovskite nanocrystal Electrohydrodynamic inkjet printing Color conversion microstructures arrays Micro-LED display
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