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An Efficient and Stable Ionic Liquid System for Synthesis of Ethylene Glycol via Hydrolysis of Ethylene Carbonate 被引量:9
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作者 MENG Zhenying SUN Jian +4 位作者 WANG Jinquan ZHANG Jianxin FU Zengzeng CHENG Weiguo ZHANG Xiangping 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期962-966,共5页
An ionic liquid system of [Bmim]X/[Bmim]OH(X Cl,BF4,and PF6,) was developed for the hydroly-sis of ethylene carbonate to ethylene glycol. The important parameters,such as the variety of ionic liquids,molar ratio of [B... An ionic liquid system of [Bmim]X/[Bmim]OH(X Cl,BF4,and PF6,) was developed for the hydroly-sis of ethylene carbonate to ethylene glycol. The important parameters,such as the variety of ionic liquids,molar ratio of [Bmim]X to [Bmim]OH,amount of ionic liquid,molar ratio of water to ethylene carbonate,reaction tem-perature,pressure and reaction time,were investigated systematically. Excellent yield(>93%) and high selectivity(99.5%) of ethylene glycol were achieved. Under the optimum reaction conditions,the ionic liquid system could be reused at least five times and the selectivity of ethylene glycol remained higher than 99.5%. 展开更多
关键词 ethylene carbonate ethylene glycol HYDROLYSIS ionic liquids CATALYSIS
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Simulation of drop breakage in liquid–liquid system by coupling of CFD and PBM: Comparison of breakage kernels and effects of agitator configurations 被引量:2
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作者 Rui Xie Jun Li +2 位作者 Yang Jin Da Zou Ming Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第5期1001-1014,共14页
This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two dif... This work focuses on drop breakage for liquid-liquid system with an adoption of numerical simulation by using computational fluid dynamics and population balance model (PBM) coupled with two-fluid model (TFM). Two different breakage kernels based on identical breakage mechanism but different descriptions of breaking time are take n into account in this work. Eight cases corresp on ding to distinct configurations of agitator are carried out to validate numerical predictions, namely agitators with different porosity and hole diameters, respectively implemented in Cases 1 to 5 and Cases 6 to 8. The results are compared with experimental data for testing the applicability of both kernels. Simulations are implemented, in this work, with an approach of class method for the solution of population balance model by the special-purpose computational fluid dynamics solver Fluent 16.1 based on finite volume method, and the grids used for meshing the solution domain are accomplished in a commercial software Gambit 2.4.6. The effects of configurations of agitator corresponding to different parameters mentioned above on final Sauter mean diameter are equally concentrated in this work. Analysis of both kernels and comparisons with experimental results reveal that, the second kernel has more decent agreement with experiments, and the results of investigations on effects of agitator configurations show that the in fluences of these parameters on Sauter mean diameter are marginal, but appropriate porosity and hole diameter are actually able to decrease Sauter mean diameter. These outcomes allow us to draw general conclusions and help investigate performances of liquid-liquid system. 展开更多
关键词 Stirred vessel liquid-liquid system Computational fluid dynamics Population balance model BREAKAGE kernel AGITATOR configuration
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Existence forms of water in solid liquid systems
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作者 刑军 刘正宁 +5 位作者 李昕跃 刘荣 黄慧 徐海燕 徐继润 任顺年 《中国有色金属学会会刊:英文版》 CSCD 2000年第5期680-682,共3页
Two approaches, named pressure filtration (PF) and vaporization dewatering (VD), for qualitative and quantitative analysis of the water forms were presented. The principle of VD is that with the process of heating, th... Two approaches, named pressure filtration (PF) and vaporization dewatering (VD), for qualitative and quantitative analysis of the water forms were presented. The principle of VD is that with the process of heating, the free water, surface water and capillary water are in turn vaporized at different rates, then the turning points of the rates are determined and the quantitative analysis can be made. Some experiments with suspension of water and CaCO 3 powder were given and discussed by applying the vaporization dewatering approach. [ 展开更多
关键词 SOLID liquid separation EXISTENCE FORMS of WATER VAPORIZATION DEWATERING
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Recent Advances in Quantum Spin Liquids in Two-Dimensional Kagome System YCu_(3)(OH)_(6+x)X_(3-x)(X=Cl,Br)
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作者 Shiliang Li 《Chinese Physics Letters》 2025年第7期419-427,共9页
The two-dimensional kagome lattice serves as a prototypical platform for exploring quantum spin liquids owing to its pronounced geometric frustration.Substantial advancements have been achieved in herbertsmithite and ... The two-dimensional kagome lattice serves as a prototypical platform for exploring quantum spin liquids owing to its pronounced geometric frustration.Substantial advancements have been achieved in herbertsmithite and its structural analogs.These quantum spin liquid candidates exhibit large superexchange interactions yet resist magnetic ordering down to the lowest measurable temperatures,which are typically three or four orders of magnitude below the energy scale of the primary exchange energies.Nevertheless,the existence of unavoidable intrinsic interlayer magnetic impurities leads to persistent debates on their ground states.A breakthrough emerged with the discovery of YCu_(3)(OH)_(6+x)X_(3-x)(X=Cl,Br),a novel material family rigorously verifed to eliminate magnetic impurity interference.This short review highlights critical advances in these materials,emphasizing experimental signatures consistent with a Dirac quantum spin liquid and the observation of a oneninth magnetization plateau and possible quantum oscillations.Local structural characteristics play a crucial role in clarifying the complex emergent quantum phenomena of these materials.Collectively,these fndings establish this material class as a promising platform for investigating quantum spin liquid behavior in two-dimensional kagome lattices. 展开更多
关键词 two dimensional kagome system magnetic impurities superexchange interactions quantum spin liquid ycu oh x x x quantum spin liquids kagome lattice magnetic ordering
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LIOUVILLE THEOREM FOR 3D STATIONARY Q-TENSOR SYSTEM OF LIQUID CRYSTAL
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作者 HU Li-li ZHOU Yan-ping BIE Qun-yi 《数学杂志》 2025年第4期283-292,共10页
In this paper,we study Liouville theorem for the 3D stationary Q-tensor system of liquid crystal in Lorentz and Morrey spaces.Under some additional hypotheses,stated in terms of Lorentz and Morrey spaces,using energy ... In this paper,we study Liouville theorem for the 3D stationary Q-tensor system of liquid crystal in Lorentz and Morrey spaces.Under some additional hypotheses,stated in terms of Lorentz and Morrey spaces,using energy estimation,we obtain that the trivial solution u=Q=0 is the unique solution.Our theorems correspond to improvements of some recent results and contain some known results as particular cases. 展开更多
关键词 Lorentz spaces Morrey spaces Q-tensor liquid crystal Liouville theorem
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Development of a Liquid Desiccant Air Conditioning System Using Ionic Liquids
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作者 Hiroshi Nakayama Masatoshi Harada Xinming Wang 《Journal of Civil Engineering and Architecture》 2025年第2期74-81,共8页
LDACs(liquid desiccant air-conditioners)with heat pump can perform cooling dehumidification or heating humidification,and have high energy-saving and sterilization performance.Therefore,they are installed in hospitals... LDACs(liquid desiccant air-conditioners)with heat pump can perform cooling dehumidification or heating humidification,and have high energy-saving and sterilization performance.Therefore,they are installed in hospitals,nursing homes,and food factories,where humidity control is required.However,LiCl(lithium chloride),a conventional humidity control liquid,is highly corrosive to metals,requiring the use of highly corrosion-resistant materials for the pipes and the heat exchangers.These lead to the problem that the manufacturing cost of the air conditioner increases.Therefore,we developed an inexpensive and compact LDAC by adopting a novel IL(ionic liquid)that does not corrode the metals commonly used in air conditioners.In this study,we evaluated the metal solubilities and sterilizing properties of the IL.Based on the physical properties of the IL,the humidity control module was improved for the purpose of downsizing and cost reduction of the unit.Moreover,we conducted a performance evaluation of the LDAC in the environmental test room under the condition in which temperature and humidity change rapidly in short period of time to simulate the condition of sudden showers of rain in summer.Test results showed that processed air was supplied at very stable level. 展开更多
关键词 liquid desiccant air conditioning ILS heat pump DEHUMIDIFICATION
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Solid−liquid phase diagram of the KNO_(3)-Ca(NO_(3))_(2)-Mg(NO_(3))_(2)-H_(2)O system at 313.15 K
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作者 Xiangxia Zeng Tao Zhang +3 位作者 Li Lv Wenxiang Tang Zongpeng Zou Shengwei Tang 《Chinese Journal of Chemical Engineering》 2025年第2期93-107,共15页
The enrichment of low-grade phosphate rock is an important process to realize sustainable support of phosphorus resources. An aqueous solution containing Ca(NO_(3))_(2) and Mg(NO_(3))_(2) is produced during the enrich... The enrichment of low-grade phosphate rock is an important process to realize sustainable support of phosphorus resources. An aqueous solution containing Ca(NO_(3))_(2) and Mg(NO_(3))_(2) is produced during the enrichment of low-grade phosphate rock by leaching of HNO_(3) or calcination coupling with leaching of NH_(4)NO_(3) solution. Preparation liquid fertilizer is a preferential way to utilize it. The liquid−solid phase diagrams of Ca(NO_(3))_(2)-Mg(NO_(3))_(2)-H_(2)O, KNO_(3)-Mg(NO_(3))_(2)-H_(2)O, KNO_(3)-Ca(NO_(3))_(2)-H_(2)O and KNO_(3)-Ca(NO_(3))_(2)-Mg(NO_(3))_(2)-H_(2)O systems at 313.15 K were studied by isothermal dissolution equilibrium method. Two crystallization regions of Ca(NO_(3))_(2)·4H_(2)O and Mg(NO_(3))_(2)·6H_(2)O were observed in the phase diagram of the ternary system Ca(NO_(3))_(2)-Mg(NO_(3))_(2)-H_(2)O, a liquid fertilizer with a maximal total nutrient content of 27.46% and a nutrients ratio of N:Ca:Mg = 8.40:10.37:1 can be formed. A homogenous solution can be formed by mixing Ca(NO_(3))_(2)·4H_(2)O and Mg(NO_(3))_(2)·6H_(2)O. In the ternary system KNO_(3)-Mg(NO_(3))_(2)-H_(2)O, the crystallization regions of KNO_(3), Mg(NO_(3))_(2)·6H_(2)O and the co-crystallization region of KNO_(3) and Mg(NO_(3))_(2)·6H_(2)O were observed. The obtained maximal total nutrient content of liquid fertilizer is 23.32% with the ratio of N:K_(2)O = 1:3.39. In the ternary system KNO_(3)-Ca(NO_(3))_(2)-H_(2)O, the crystallization regions of Ca(NO_(3))_(2)·4H_(2)O and KNO_(3) were observed. The obtained maximal total nutrient content of liquid fertilizer is 38.41% with the ratio of N:K_(2)O:Ca = 1.05:1.18:1. A homogenous solution can also be formed by mixing Ca(NO_(3))_(2)·4H_(2)O and KNO_(3) directly. In the quaternary system KNO_(3)-Ca(NO_(3))_(2)-Mg(NO_(3))_(2)-H_(2)O, the crystallization regions of Ca(NO_(3))_(2)·4H_(2)O, Mg(NO_(3))_(2)·6H_(2)O and KNO_(3) and the co-crystallization region of KNO_(3) and Mg(NO_(3))_(2)·6H_(2)O were observed. The obtained maximal total nutrient content of liquid fertilizer is 38.41% with the ratio of N:K_(2)O:Ca = 1.05:1.18:1. The modified BET model was successfully used to fit the solubility curves. The results can provide a guidance for the formulation of water-soluble fertilizers of N-(K, Ca, Mg). 展开更多
关键词 Calcium nitrate Magnesium nitrate liquid water-soluble fertilizer Phase equilibria BET model
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Multi-scale analysis of the self-vibration of a liquid crystal elastomer fiber-spring system exposed to constant-gradient light
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作者 Haiyang WU Jiangfeng LOU +2 位作者 Yuntong DAI Biao ZHANG Kai LI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第7期652-665,共14页
Self-vibrating systems comprised of active materials have great potential for application in the fields of energy harvesting,actuation,bionic instrumentation,and autonomous robotics.However,it is challenging to obtain... Self-vibrating systems comprised of active materials have great potential for application in the fields of energy harvesting,actuation,bionic instrumentation,and autonomous robotics.However,it is challenging to obtain analytical solutions describing these systems,which hinders analysis and design.In this work,we propose a self-vibrating liquid crystal elastomer(LCE)fiber-spring system exposed to spatially-constant gradient light,and determine analytical solutions for its amplitude and period.First,using a dynamic model of LCE,we obtain the equations governing the self-vibration.Then,we analyze two different motion states and elucidate the mechanism of self-vibration.Subsequently,we derive analytical solutions for the amplitude and frequency using the multi-scale method,and compare the solutions with numerical results.The analytical outcomes are shown to be consistent with the numerical calculations,while taking far less computational time.Our findings reveal the utility of the multi-scale method in describing self-vibration,which may contribute to more efficient and accurate analyses of self-vibrating systems. 展开更多
关键词 Self-vibration Constant-gradient light liquid crystal elastomer(LCE) Multi-scale method FIBER Spring oscillator
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Experimental Study on a Hybrid Battery Thermal Management System Combining Oscillating Heat Pipe and Liquid Cooling
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作者 Hongkun Lu M.M.Noor K.Kadirgama 《Frontiers in Heat and Mass Transfer》 2025年第1期299-324,共26页
To improve the thermal performance and temperature uniformity of battery pack,this paper presents a novel battery thermal management system(BTMS)that integrates oscillating heat pipe(OHP)technology with liquid cooling... To improve the thermal performance and temperature uniformity of battery pack,this paper presents a novel battery thermal management system(BTMS)that integrates oscillating heat pipe(OHP)technology with liquid cooling.The primary innovation of the new hybrid BTMS lies in the use of an OHP with vertically arranged evaporator and condenser,enabling dual heat transfer pathways through liquid cooling plate and OHP.This study experimentally investigates the performance characteristics of the⊥-shaped OHP and hybrid BTMS.Results show that lower filling ratios significantly enhance the OHP’s startup performance but reduce operational stability,with optimal performance achieved at a 26.1%filling ratio.Acetone,as a single working fluid,exhibited superior heat transfer performance under low-load conditions compared to mixed fluids,while the acetone/ethanol mixture,forming a non-azeotropic solution,minimized temperature fluctuations.At 100 W,the⊥-shaped OHP with a horizontally arranged evaporator demonstrated better heat transfer performance than 2D-OHP designs.Compared to a liquid BTMS using water coolant at 280 W,the hybrid BTMS reduced the equivalent thermal resistance(RBTMS)and maximum temperature difference(ΔTmax)by 8.06%and 19.1%,respectively.When graphene nanofluid was used as the coolant in hybrid BTMS,the battery pack’s average temperature(Tb)dropped from 52.2℃ to 47.9℃,with RBTMS andΔTmax decreasing by 20.1%and 32.7%,respectively.These findings underscore the hybrid BTMS’s suitability for high heat load applications,offering a promising solution for electric vehicle thermal management. 展开更多
关键词 Battery thermal management system oscillating heat pipe liquid cooling hybrid BTMS graphene nanofluid
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Liouville Theorem for 3D Steady Q-Tensor System of Liquid Crystal in Mixed Lorentz Spaces
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作者 WAN Mengru DENG Xuemei BIE Qunyi 《Wuhan University Journal of Natural Sciences》 2025年第3期235-240,共6页
this paper,we study Liouville theorem for 3D steady Q-tensor system of liquid crystal in mixed Lorentz spaces.We obtain u=0,Q=0 on the conditions that μ∈L^(p,∞x_(1)L^(q,∞x_(2)L^(r,∞x_(3)(R^(4)∩H^(1)(R^(3),Q∈H^(... this paper,we study Liouville theorem for 3D steady Q-tensor system of liquid crystal in mixed Lorentz spaces.We obtain u=0,Q=0 on the conditions that μ∈L^(p,∞x_(1)L^(q,∞x_(2)L^(r,∞x_(3)(R^(4)∩H^(1)(R^(3),Q∈H^(2)(R^(3),p,q,r∈(3,∞],and 1/p+1/q+1/r≥2/3, which extends some known results. 展开更多
关键词 mixed Lorentz spaces Q-tensor system of liquid crystal Liouville theorem
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Aqueous Ionic Liquid Mediated Hydrolysis of Native Corn Starch to Obtain Different Low Molecular Weight Starch
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作者 YANG Rui WANG Xiaolin +1 位作者 DANG Qian LIU Zhengping 《高等学校化学学报》 北大核心 2026年第1期153-161,共9页
In this work,we proposed a strategy for the hydrolysis of native corn starch after the treatment of corn starch in an ionic liquid aqueous solution,and it is an awfully“green”and simple means to obtain starch with l... In this work,we proposed a strategy for the hydrolysis of native corn starch after the treatment of corn starch in an ionic liquid aqueous solution,and it is an awfully“green”and simple means to obtain starch with low molecular weight and amorphous state.X-ray diffraction results revealed that the natural starch crystalline region was largely disrupted by ionic liquid owing to the broken intermolecular and intramolecular hydrogen bonds.After hydrolysis,the morphology of starch changed from particles of native corn starch into little pieces,and their molecular weight could be effectively regulated during the hydrolysis process,and also the hydrolyzed starch samples exhibited decreased thermal stability with the extension of hydrolysis time.This work would counsel as a powerful tool for the development of native starch in realistic applications. 展开更多
关键词 Native corn starch Ionic liquid HYDROLYSIS Molecular weight
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Advancing pediatric cancer diagnosis: the promise of single-cell liquid biopsy for early detection and surveillance
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作者 Pavithra Ayyadurai Chinnasamy Ragavendran 《Biomedical Engineering Communications》 2026年第1期13-25,共13页
Pediatric cancers are particularly significant due to their uncommon occurrence in children,driven by a variety of underlying factors.Because of their distinct molecular and genetic makeup,which makes early detection ... Pediatric cancers are particularly significant due to their uncommon occurrence in children,driven by a variety of underlying factors.Because of their distinct molecular and genetic makeup,which makes early detection challenging,they are linked to problems.Diagnostic methods like imaging and tissue biopsy are only effective when the tumor has reached a size that can be identified.The liquid biopsy technique,the least intrusive and most convenient diagnostic method,is the subject of this review.It focuses on the significance of single cell analysis in examining uncommon cancer types.The many biomarkers found in bodily fluids and the cancer types they are linked to in children have been assessed,as has the potential route towards early detection and cancer recurrence forecasting.Combining the single cell liquid biopsy with the newest technologies,such as computational and multi-omics approaches,which have improved the efficiency of processing massive and unique genetic data,appears promising.This article discusses on a number of case reports for uncommon pediatric malignancies,such as Neuroblastoma,Medulloblastoma,Wilms Tumor,Rhabdomyosarcoma,Ewing Sarcoma,and Retinoblastoma,as well as their liquid biopsy profiles.Furthermore,the findings raise ethical questions regarding the therapeutic application of the technology as well as possible difficulties related to clinical translation.The likelihood that this single cell liquid biopsy will be clinically validated and eventually used as a routine diagnostic tool for uncommon pediatric cancers will rise with the realistic approach to sensitivity monitoring,specificity upgrading,and optimization. 展开更多
关键词 pediatric cancer single cell liquid biopsy biomarkers NEUROBLASTOMA MEDULLOBLASTOMA wilms tumor
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Nature-Inspired Upward Hanging Evaporator with Photothermal 3D Spacer Fabric for Zero-Liquid-Discharge Desalination
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作者 Ye Peng Yang Shao +3 位作者 Longqing Zheng Haoxuan Li Meifang Zhu Zhigang Chen 《Nano-Micro Letters》 2026年第1期545-561,共17页
While desalination is a key solution for global freshwater scarcity,its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems.Solar interfa... While desalination is a key solution for global freshwater scarcity,its implementation faces environmental challenges due to concentrated brine byproducts mainly disposed of via coastal discharge systems.Solar interfacial evaporation offers sustainable management potential,yet inevitable salt nucleation at evaporation interfaces degrades photothermal conversion and operational stability via light scattering and pathway blockage.Inspired by the mangrove leaf,we propose a photothermal 3D polydopamine and polypyrrole polymerized spacer fabric(PPSF)-based upward hanging model evaporation configuration with a reverse water feeding mechanism.This design enables zero-liquiddischarge(ZLD)desalination through phase-separation crystallization.The interconnected porous architecture and the rough surface of the PPSF enable superior water transport,achieving excellent solar-absorbing efficiency of 97.8%.By adjusting the tilt angle(θ),the evaporator separates the evaporation and salt crystallization zones via controlled capillary-driven brine transport,minimizing heat dissipation from brine discharge.At an optimal tilt angle of 52°,the evaporator reaches an evaporation rate of 2.81 kg m^(−2) h^(−1) with minimal heat loss(0.366 W)under 1-sun illumination while treating a 7 wt%waste brine solution.Furthermore,it sustains an evaporation rate of 2.71 kg m^(−2) h^(−1) over 72 h while ensuring efficient salt recovery.These results highlight a scalable,energy-efficient approach for sustainable ZLD desalination. 展开更多
关键词 DESALINATION Solar interfacial evaporation Biomimetic design Zero liquid discharge Thermal management
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Liquid biopsies in psychiatric disorders:Identifying peripheral biomarkers of brain health
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作者 Jennifer L.Payne Sarven Sabunciyan 《Neural Regeneration Research》 2026年第2期691-692,共2页
The inability to access brain tissue has greatly hindered our ability to study and care for individuals suffering from psychiatric and neurological conditions.Critics have questioned efforts to develop peripheral bloo... The inability to access brain tissue has greatly hindered our ability to study and care for individuals suffering from psychiatric and neurological conditions.Critics have questioned efforts to develop peripheral blood biomarkers in neurological and psychiatric disorders based on the assertion that disease pathology is limited to the brain.The discovery that all tissues,including the brain,release extracellular vesicles(Raposo and Stoorvogel,2013)and cell free DNAs(Chan et al.,2013)into various body fluids has provided a potential way to measure activity from inaccessible tissues like the central nervous system(CNS)and has given rise to the term“liquid biopsy.”The development of liquid biopsies that can diagnose and predict the course of psychiatric and neurological disorders would be transformative.The ability to predict episodic events such as mania,depression,and risk for suicide would be particularly useful for psychiatric care as it would enable the development of interventions that prevent mortality and improve outcomes.Additionally,biomarkers that are informative about drug response and aid in treatment decisions would be a significant advance in psychiatric care as it would prevent patients from having to endure multiple courses of ineffective treatments and side effects. 展开更多
关键词 develop peripheral blood biomarkers liquid biopsies study care individuals cell free dnas chan extracellular vesicles raposo body fluids neurological psychiatric disorders peripheral biomarkers
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Laser Flash Photolysis Mechanism of Anthraquinone-2-Sodium Sulfonate in Pyridine Ionic Liquid/Water Mixed System
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作者 朱光来 张良伟 +3 位作者 刘艳成 崔执凤 许新胜 吴国忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期140-146,I0003,共8页
The photochemical reaction process of anthraquinone-2-sodium sulfonate (AQS) in the mixture of water (H2O) and N-butylpyridinium tetrafluoroborate ([BPy] [BF4]) was studied using the laser flash photolysis techn... The photochemical reaction process of anthraquinone-2-sodium sulfonate (AQS) in the mixture of water (H2O) and N-butylpyridinium tetrafluoroborate ([BPy] [BF4]) was studied using the laser flash photolysis technique. Experimental results show that the excited triplet of AQS (3AQS*) could react rapidly with H2O and the transient absorption spectra greatly changed by increasing the volume fraction of the ionic liquid (VIL) in [BPy][BF4]/H2O mixtures. The absorbance at 510 nm increased gradually with increasing VIL when 0〈VIL〈0.1. By contrast, the absorbance decreased gradually when VIL〉0.1. Otherwise, the absorbance of the band near 380 nm steadily increased. The apparent kinetic parameters of transient species B and ^3AQS* are obtained approximately. 3AQS* abstracting hydrogen from [BPy]+ was also explored. It was deduced that the 350-420 nm band was the superposition of the peaks of 3AQS* and AQSH'. The two reactions of 3AQS* with [BPy][BF4] and H2O are a pair of competitive reactions. We also concluded that the entire reaction processes slow down in the case of high [BPy] [BF4] concentrations. 展开更多
关键词 Laser flash photolysis Anthraquinone-2-sodium sulfonate Ionic liquids Tran- sient absorption Hydrogen abstraction
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A novel liquid system of catalytic hydrogenation 被引量:7
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作者 LI XiaoNian XIANG YiZhi 《Science China Chemistry》 SCIE EI CAS 2007年第6期746-753,共8页
On the basis that endothermic aqueous-phase reforming of oxygenated hydrocarbons for H2 produc- tion and exothermic liquid phase hydrogenation of organic compounds are carried out under extremely close conditions of t... On the basis that endothermic aqueous-phase reforming of oxygenated hydrocarbons for H2 produc- tion and exothermic liquid phase hydrogenation of organic compounds are carried out under extremely close conditions of temperature and pressure over the same type of catalyst, a novel liquid system of catalytic hydrogenation has been proposed, in which hydrogen produced from aqueous-phase re- forming of oxygenated hydrocarbons is in situ used for liquid phase hydrogenation of organic com- pounds. The usage of active hydrogen generated from aqueous-phase reforming of oxygenated hy- drocarbons for liquid catalytic hydrogenation of organic compounds could lead to increasing the se- lectivity to H2 in the aqueous-phase reforming due to the prompt removal of hydrogen on the active centers of the catalyst. Meanwhile, this novel liquid system of catalytic hydrogenation might be a po- tential method to improve the selectivity to the desired product in liquid phase catalytic hydrogenation of organic compounds. On the other hand, for this novel liquid system of catalytic hydrogenation, some special facilities for H2 generation, storage and transportation in traditional liquid phase hydrogenation industry process are yet not needed. Thus, it would simplify the working process of liquid phase hy- drogenation and increase the energy usage and hydrogen productivity. 展开更多
关键词 NOVEL HYDROGENATION reaction AQUEOUS-PHASE reforming liquid CATALYTIC hydrogenation coupling
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Extraction of Theanine from Waste Liquid of Tea Polyphenol Production in Aqueous Two-phase Systems with Cationic and Anionic Surfactants 被引量:8
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作者 张军伟 王艳 彭奇均 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期31-36,共6页
Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that ... Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system (ASTP) with cationic surfactant (CTAB) and anionic surfactant (SDS). Results indicate that the region of ASTP is narrow and there is only a two-phase region of cationic surfactant. The increase in concentrations of NaBr and Na2SO4 are beneficial to the formation of ASTP. Theanine concentration in the bottom phase increases with increasing concentration of theanine, whereas the Partition coefficient and extraction rate only change a littlewhen the concentration of theanine is above 0.2 g.L-'. With the increase of SDS concentration, the phase ratio and the partition coefficient decrease, while the extraction efficiency of theanine increases and the concentration of theanine changes a little in the range from 2.4/7.5 to 2.8/7.2 for SDS/CTAB ratio. The temperature has a notable ef- fect on the concentration of theanine in the bottom phase, partition coefficient and extraction rate of theanine. The increase of waste liquid decreases the phase ratio, increases the concentration and extraction rate of theanine in the bottom ohase, since the orotein and the saccharide enter the bottom nhase with theanine. 展开更多
关键词 aqueous two-phase system SURFACTANT THEANINE waste liquid of tea polyphenol production EXTRACTION
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Design of ionic liquids as liquid desiccant for an air conditioning system 被引量:3
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作者 Haruki Watanabe Takuro Komura +4 位作者 Ryo Matsumoto Kenta Ito Hiroshi Nakayama Toshiki Nokami Toshiyuki Itoh 《Green Energy & Environment》 SCIE CSCD 2019年第2期139-145,共7页
Suitable control of the humidity can contribute to electric energy savings. However, the present dehumidification system has many weak points. The liquid desiccant air-conditioning system has recently gained growing i... Suitable control of the humidity can contribute to electric energy savings. However, the present dehumidification system has many weak points. The liquid desiccant air-conditioning system has recently gained growing interest from the stand point of reducing energy consumption during dehumidification. In order to find the appropriate ionic liquids(ILs) as a desiccant for the liquid desiccant air-conditioner system, we conducted a systematic evaluation of the humidification capability of 16 types of ILs. Among the tested ILs, tributyl(methyl)phosphonium dimethyl phosphate([P4441][DMPO_4]) exhibited the best dehumidification capacity and had a less corrosive effect on four types of metals as possible piping materials. It should be noted that this [P_(4441)][DMPO_4] has a very stable nature and produced no odor while conducting the experiment and storing for over 1 year at room temperature under ambient conditions. Furthermore, it was revealed that a 77%(w/w) aqueous solution of [P4441][DMPO_4] worked as an efficient desiccant liquid for the liquid desiccant air-conditioner system. 展开更多
关键词 DEHUMIDIFICATION liquid DESICCANT Ionic liquids AIR-CONDITIONER system PHOSPHONIUM ILS
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Effects of imidazolium-based ionic liquids on the isobaric vapor–liquid equilibria of methanol+dimethyl carbonate azeotropic systems 被引量:4
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作者 Songsong Chen Li Dong +4 位作者 Junping Zhang Weiguo Cheng Feng Huo Qian Su Wei Hua 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第3期766-776,共11页
The separation of methanol(MeOH)and dimethyl carbonate(DMC)is important but difficult due to the formation of an azeotropic mixture.In this work,isobaric vapor–liquid equilibrium(VLE)data for the ternary systems cont... The separation of methanol(MeOH)and dimethyl carbonate(DMC)is important but difficult due to the formation of an azeotropic mixture.In this work,isobaric vapor–liquid equilibrium(VLE)data for the ternary systems containing different imidazolium–based ionic liquids(ILs),i.e.MeOH+DMC+1-butyl-3-methy-limidazolium bis[(trifluoromethyl)sulfonyl]imide([Bmim][Tf2N]),MeOH+DMC+1-ethyl-3-methyl-imidazolium bis[(trifluoromethyl)sulfonyl]imide([Emim][Tf2N]),and MeOH+DMC+1-ethyl-3-methylimidazolium hexafluorophosphate([Emim][PF6])were measured at 101.3 kPa.The mole fraction of IL was varied from0.05 to 0.20.The experimental data were correlated with the NRTL and Wilson equations,respectively.The results show that imidazolium-based ILs were beneficial to improve the relative volatility of MeOH to DMC,and[Bmim][Tf2 N]showed a much more excellent performance on the activity coefficient of MeOH.The interaction energies of system components were calculated using Gaussian program,and the effects of cation and anion on the separation coefficient of the azeotropic system were discussed. 展开更多
关键词 Vapor liquid equilibria Ionic liquid AZEOTROPE Separation Interaction energy
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Molecular interaction mechanism in the separation of a binary azeotropic system by extractive distillation with ionic liquid 被引量:6
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作者 Hong Li Guanlun Sun +5 位作者 Dongyang Li Li Xi Peng Zhou Xingang Li Ji Zhang Xin Gao 《Green Energy & Environment》 SCIE CSCD 2021年第3期329-338,共10页
Ionic liquids(ILs)have shown excellent performance in the separation of binary azeotropes through extractive distillation[1].But the role of the ionic liquid in azeotropic system is not well understood.In this paper,C... Ionic liquids(ILs)have shown excellent performance in the separation of binary azeotropes through extractive distillation[1].But the role of the ionic liquid in azeotropic system is not well understood.In this paper,COSMO-RS model was applied to screen an appropriate IL to separate the binary azeotrope of ethyl acetate(EA)and ethanol and 1-octyl-3-methylimidazolium tetrafluoroborate([OMIM][BF4])was selected.The Quantum Mechanics(QM)calculations and molecular dynamics(MD)simulation are performed to study the interactions between the solvent molecules and[OMIM][BF4],in order to investigate the separation mechanism at the molecular level.The nature of the interactions is studied through the reduced density gradient(RDG)function and quantum theory of Atom in Molecule(QTAIM).Hydrogen bonds and van der Waals interactions are the key interactions in the complexes.The results of MD simulations indicate that the introduction of ILs has a prominent effect on the interaction between the solvent molecules,especially on reducing the number of hydrogen bonds among the solvent molecules.The radial distribution function(RDF)reveals that the interaction between the cation and solvent molecules will increase while the concentration of ILs increases.This paper provides important information for understanding the role of ILs in the separation of the azeotropic system,which is valuable to the development of new entrainers. 展开更多
关键词 Ionic liquids AZEOTROPE Density functional theory SEPARATION Extractive distillation
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