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Study on the condensation behavior of magnesium vapor by flow field disturbance under relative vacuum
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作者 Jing-zhong Xu Ting-an Zhang Hong-xuan Liu 《Journal of Magnesium and Alloys》 2025年第3期1116-1132,共17页
Compared with Pidgeon process,the relative vacuum continuous magnesium smelting process reduces the ratio of material to magnesium by changing raw materials and the direct reduction after calcination of prefabricated ... Compared with Pidgeon process,the relative vacuum continuous magnesium smelting process reduces the ratio of material to magnesium by changing raw materials and the direct reduction after calcination of prefabricated pellets,so that the energy consumption per ton of magnesium produced is reduced by 30∼40%,and the carbon emission is reduced by 43∼52%,breaking through the vacuum conditions to achieve continuous production.However,in the process of industrialization,it was found that the magnesium yield in the condenser was low.Therefore,this paper constructs a condenser model of relative vacuum continuous magnesium refining process,and comprehensively analyzes the condensation mechanism of magnesium vapor through simulation and experiment.It is found that the dynamic characteristics of magnesium vapor condensation is an important index to measure its continuity.Under the condition offlowing argon as the protective gas,when the condensation plate spacing is 10 cm,the surface roughness amplitude variance is 2,and the carrier gasflow rate is 20×10^(-3) m/s,the magnesium vapor has a better condensation effect,and the condensation efficiency formula is derived. 展开更多
关键词 Relative vacuum Flow field disturbance Pidgeon MAGNESIUM condensation CONTINUITY
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Recyclable and Self-healable Polydimethylsiloxane Elastomers Based on Knoevenagel Condensation
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作者 Yao-Wei Zhu Tong-Tong Man +5 位作者 Ming-Ming Zhao Jia-Yi Chen Yu Yan Xiao-Nong Zhang Li Chen Chun-Sheng Xiao 《Chinese Journal of Polymer Science》 2025年第1期53-60,I0007,共9页
Elastomers are widely used in various fields owing to their excellent tensile properties.Recyclable and self-healing properties are key to extending the service life of elastomers.Accumulating evidence indicates that ... Elastomers are widely used in various fields owing to their excellent tensile properties.Recyclable and self-healing properties are key to extending the service life of elastomers.Accumulating evidence indicates that dynamic covalent chemistry has emerged as a powerful tool for constructing recyclable and self-healing materials.In this work,we demonstrate the preparation of a recyclable and self-healable polydimethylsiloxane(PDMS)elastomer based on the Knoevenagel condensation(KC)reaction.This PDMS elastomer was prepared by the KC reaction catalyzed by 4-dimethylaminopyridine(DMAP).The obtained PDMS elastomer exhibited an elongation at break of 266%,a tensile strength of 0.57 MPa,and a good thermal stability(Td=357℃).In addition,because of the presence of dynamic C=C bonds formed by the KC reaction and low glass transition temperature(Tg=-117℃).This PDMS exhibited good self-healing and recycling properties at room temperature and could be reprocessed by hot pressing.In addition,the PDMS elastomer exhibits good application prospects in the fields of adhesives and flexible electronic devices. 展开更多
关键词 Dynamic covalent chemistry ELASTOMER Knoevenagel condensation reaction POLYDIMETHYLSILOXANE RECYCLABLE SELF-HEALING
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Heterogeneously catalyzed self-condensation of n-butanal
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作者 Yaqi Qu Hualiang An +1 位作者 Xinqiang Zhao Yanji Wang 《Chinese Journal of Chemical Engineering》 2025年第4期89-99,共11页
The self-condensation of n-butanal is an important reaction for carbon-chain extension in the commercial production of 2-ethylhexanol.Moreover,aldol condensation is one of the important reactions for the synthesis of ... The self-condensation of n-butanal is an important reaction for carbon-chain extension in the commercial production of 2-ethylhexanol.Moreover,aldol condensation is one of the important reactions for the synthesis of valuable organic chemicals or transportation fuels from biomass-derived platform compounds.So the investigation of the self-condensation of n-butanal is of significance in both academia and industry.This contribution reviewed the catalytic performance of heterogeneous catalysts in the self-condensation of n-butanal and the related reaction mechanism,network,and kinetics.The purpose of this review is to dedicate some help for further development of environmentally friendly catalysts and for a thorough comprehension of aldol condensation. 展开更多
关键词 Aldol condensation N-BUTANAL Solid catalyst Reaction mechanism Reaction network Reaction kinetics
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Design and fabrication of triangle-pattern superwettability hybrid surface with high-efficiency condensation heat transfer performance
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作者 Rui Wang Yuan Tian +1 位作者 Xuefeng Gao Lei Jiang 《Chinese Chemical Letters》 2025年第3期449-453,共5页
Utilizing superwettability micro/nanostructures to enhance the condensation heat transfer(CHT)performance of engineering materials has attracted great interest due to its values in basic research and technological inn... Utilizing superwettability micro/nanostructures to enhance the condensation heat transfer(CHT)performance of engineering materials has attracted great interest due to its values in basic research and technological innovations.Currently,exploring facile micro/nanofabrication approaches to create high-efficiency CHT surfaces has been one of research hotspots.In this work,we propose and demonstrate a type of new superwettability hybrid surface for high-efficiency CHT,which consists of superhydrophobic nanoneedle arrays and triangularly-patterned superhydrophilic microdots(SMDs).Such hybrid surface can be fabricated by the facile growth of densely-packed ZnO nanoneedles on the Zn-electroplated copper surface followed by fluorosilane modification and mask-assisted photodegradation.Through regulating the diameters and interspaces of SMDs,we obtain the optimized triangularly-patterned hybrid surface,which shows 42.7%higher CHT coefficient than the squarely-patterned hybrid surface and 58.5%higher CHT coefficient than the superhydrophobic surface.The key of such hybrid surface design is to considerably increase CHT coefficient brought about by SMD-triggered drop sweeping at the cost of slightly reducing heat transfer area of superhydrophobic functional zone for drop jumping.Such new strategy helps develop advanced CHT surfaces for high-efficiency electronic cooling and energy utilization. 展开更多
关键词 Superwettability Hybrid surface SUPERHYDROPHOBIC SUPERHYDROPHILIC Patterned surfaces condensation heat transfer
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Room-temperature exciton-polariton condensation in pressed perovskite microcavities
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作者 Tianyin Zhu Zelei Chen +3 位作者 Xiaoyu Wang Zhongmin Huang Haibin Zhao Jun Wang 《Chinese Physics B》 2025年第9期186-189,共4页
Microcavity exciton-polaritons,formed by strong light-matter coupling,are essential for realizing Bose-Einstein condensation and low-threshold lasing.Such polaritonic lasing and condensation have been demonstrated in ... Microcavity exciton-polaritons,formed by strong light-matter coupling,are essential for realizing Bose-Einstein condensation and low-threshold lasing.Such polaritonic lasing and condensation have been demonstrated in Ⅲ-Ⅴ semiconductors at liquid helium temperatures.However,the complex fabrication of these microcavities and operating temperatures limit their room-temperature practical application.Here,we experimentally realize room-temperature exciton-polariton condensation and polaritonic lasing in a CsPbBr_(3)perovskite planar microcavity fabricated by the pressing process.Angleresolved photoluminescence spectra demonstrate the strong light-matter coupling and the formation of exciton-polaritons in such a pressed microcavity.Above the critical threshold,mass polaritons accumulating at the bottom of dispersion lead to a narrow emission linewidth and pronounced blueshift,further reinforcing the Bose-Einstein condensation and polaritonic lasing in this system.Our results offer a feasible and effective approach to investigate exciton-polariton condensation and polariton lasing at room temperature. 展开更多
关键词 EXCITON-POLARITON polariton condensation perovskite semiconductors optical microcavity
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A possible evidence of pion condensation
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作者 Wei Zhu Yuchen Tang +1 位作者 Lei Feng Fengyao Hou 《Communications in Theoretical Physics》 2025年第8期94-99,共6页
This work demonstrates that once a large number of pion is condensed in a high-energy hadron collision, the gamma-ray spectrum from π0decay takes on a typical broken power-law shape, which has been documented in many... This work demonstrates that once a large number of pion is condensed in a high-energy hadron collision, the gamma-ray spectrum from π0decay takes on a typical broken power-law shape, which has been documented in many astronomical observations, but we have not yet recognized it. We show that this pion condensation is caused by a large number of soft gluons condensed in protons. 展开更多
关键词 gamma-ray astronomy nuclear physics ultra-high-energy cosmic radiation pion condensation
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Carbonyl-amine condensation coupled ozonolysis of dipropylamine and styrene:Decay kinetics,reaction mechanism,secondary organic aerosol formation and cytotoxicity
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作者 Wanying Li Jiangyao Chen +2 位作者 Qinhao Lin Yuemeng Ji Taicheng An 《Journal of Environmental Sciences》 2025年第3期444-455,共12页
Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,ther... Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human health.However,there is still a lack of systematic understanding of the carbonyl-amine condensation reaction processes of OAs or between OAs and AHs,and subsequent environmental health impact.This work systematically investigated the carbonyl-amine condensation coupled ozonolysis kinetics,reaction mechanism,secondary organic aerosol(SOA)formation and cytotoxicity fromthe mixture of dipropylamine(DPA)and styrene(STY)by a combined method of productmass spectrometry identification,particle property analysis and cell exposure evaluation.The results from ozonolysis of DPA and STY mixture revealed that STY inhibited the ozonolysis of DPA to different degrees to accelerate its own decay rate.The barycenter of carbonyl-amine condensation reactionswas shifted from inside of DPA to between DPA and STY,which accelerated STY ozonolysis,but slowed down DPA ozonolysis.For the first time,ozonolysis of DPA and STY mixture to complex carbonyl-amine condensation products through the reactions of DPA with its carbonyl products,DPA with STY’s carbonyl products and DPA’s bond breakage product with STY’s carbonyl products was confirmed.These condensation products significantly contributed to the formation and growth of SOA.The SOA containing particulate carbonyl-amine condensation products showed definite cytotoxicity.These findings are helpful to deeply and comprehensively understand the transformation,fate and environmental health effects of mixed organics in atmospheric environment. 展开更多
关键词 Organic amines(OAs) Aromatic hydrocarbons(AHs) Coupled ozonolysis Carbonyl-amine condensation Secondary pollution Toxicity assessment
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Cloud Droplet Spectrum Evolution Driven by Aerosol Activation and Vapor Condensation:A Comparative Study of Different Bulk Parameterization Schemes
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作者 Jun ZHANG Jiming SUN +2 位作者 Yu KONG Wei DENG Wenhao HU 《Advances in Atmospheric Sciences》 2025年第7期1316-1332,共17页
Accurate descriptions of cloud droplet spectra from aerosol activation to vapor condensation using microphysical parameterization schemes are crucial for numerical simulations of precipitation and climate change in we... Accurate descriptions of cloud droplet spectra from aerosol activation to vapor condensation using microphysical parameterization schemes are crucial for numerical simulations of precipitation and climate change in weather forecasting and climate prediction models.Hence,the latest activation and triple-moment condensation schemes were combined to simulate and analyze the evolution characteristics of a cloud droplet spectrum from activation to condensation and compared with a high-resolution Lagrangian bin model and the current double-moment condensation schemes,in which the spectral shape parameter is fixed or diagnosed by an empirical formula.The results demonstrate that the latest schemes effectively capture the evolution characteristics of the cloud droplet spectrum during activation and condensation,which is in line with the performance of the bin model.The simulation of the latest activation and condensation schemes in a parcel model shows that the cloud droplet spectrum gradually widens and exhibits a multimodal distribution during the activation process,accompanied by a decrease in the spectral shape and slope parameters over time.Conversely,during the condensation process,the cloud droplet spectrum gradually narrows,resulting in increases in the spectral shape and slope parameters.However,these double-moment schemes fail to accurately replicate the evolution of the cloud droplet spectrum and its multimodal distribution characteristics.Furthermore,the latest schemes were coupled into a 1.5D cumulus model,and an observation case was simulated.The simulations confirm that the cloud droplet spectrum appears wider at the supersaturated cloud base and cloud top due to activation,while it becomes narrower at the middle altitudes of the cloud due to condensation growth. 展开更多
关键词 cloud microphysical parameterization cloud droplet spectrum aerosol activation cloud droplet condensation
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Regulator of chromosome condensation 1 promotes hepatocellular carcinoma proliferation via cell-division-cycle-associated-8 dependent phosphoinositide 3-kinase/protein kinase B signaling
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作者 Ya-Tao Wang Yu-Le Yong +3 位作者 Ze-Kun Liu Yi-Xuan Shen Xiang-Min Yang Zhi-Nan Chen 《World Journal of Gastrointestinal Oncology》 2025年第6期405-422,共18页
BACKGROUND Hepatocellular carcinoma(HCC)ranks among the most prevalent and deadly malignancies,characterized by a high recurrence rate.Regulator of chromosome condensation 1(RCC1)serves as a principal guanine nucleoti... BACKGROUND Hepatocellular carcinoma(HCC)ranks among the most prevalent and deadly malignancies,characterized by a high recurrence rate.Regulator of chromosome condensation 1(RCC1)serves as a principal guanine nucleotide exchange factor for ras-related nuclear protein guanosine triphosphatase(GTPase)and is implicated in various cancers.However,the role of RCC1 in HCC remains unex-plored.AIM To elucidate the functional significance and molecular mechanisms of RCC1 in HCC.METHODS Bioinformatics were to examine the expression levels of RCC1 in HCC and to assess its impact on the prognosis of this malignancy.The cell counting kit-8 assay and flow cytometry were utilized to evaluate the cell viability and cell cycle of HCC cells.Furthermore,quantitative reverse transcription and immunoblotting were to investigate the influence of RCC1 on cyclin associated proteins.RESULTS Bioinformatics analysis revealed that RCC1 was highly expressed in HCC and correlated with poor prognosis in HCC patients.Functional studies showed that RCC1 overexpression promoted the malignant phenotype of HCC cells,especially the proliferation of HCC cells,whereas RCC1 knockdown had the opposite effect.Mechanistically,we identied cell division cycle-associated(CDCA)8 as a downstream target of RCC1 in HCC.RCC1 overexpression markedly increased CDCA8 levels,consequently enhancing cell proliferation and survival in HCC cells.Additionally,we discovered that RCC1 contributed to the development and progression of HCC by activating the phosphoinositide 3-kinase/protein kinase B/cyclin-dependent kinase inhibitor 1a pathway through CDCA8.CONCLUSION Our study provides profound insights into the pivotal role of RCC1 in HCC and its potential as a therapeutic target. 展开更多
关键词 Hepatocellular carcinoma Regulator of chromosome condensation 1 PROLIFERATION Cell cycle Cell division cycleassociated 8 Phosphoinositide 3-kinase/protein kinase B pathway
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Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation 被引量:2
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作者 Wen Xiao Peng Dong +6 位作者 Chan Wang Jingdong Xu Tiesen Li Haibo Zhu Tinghai Wang Renwei Xu Yuanyuan Yue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期75-84,共10页
Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficien... Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficiency.Herein,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical 2-cyano-3-phenylacrylate.The synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or seed.Systematic characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX zeolite.Detailed mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized kaolinite.This synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing. 展开更多
关键词 Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation
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Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction
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作者 Estel Viñolas-Vergés Jordi Ribas-Maynou +4 位作者 Isabel Barranco Camila Peres Rubio Sergi Bonet Jordi Roca Marc Yeste 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期171-181,共11页
Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separa... Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separate fractions:pre-sperm,sperm-rich(SRF)and post sperm-rich(PSRF).These fractions are known to vary in volume,sperm concentration and quality,as well as in the origin and composition of seminal plasma(SP),with differences being also observed within the SRF one.Yet,whether disparities in the DNA integrity and chromatin condensation and pro-tamination of their sperm exist has not been interrogated.Results This study determined chromatin protamination(Chromomycin A3 test,CMA_(3)),condensation(Dibromobi-mane test,DBB),and DNA integrity(Comet assay)in the pig sperm contained in the first 10 m L of the SRF(SRF-P1),the remaining portion of the sperm-rich fraction(SRF-P2),and the post sperm-rich fraction(PSRF).While chromatin protamination was found to be similar between the different ejaculate fractions(P>0.05),chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF(P=0.018 and P=0.004,respectively).Regarding DNA integrity,no differences between fractions were observed(P>0.05).As the SRF-P1 has the highest sperm concentra-tion and ejaculate fractions are known to differ in antioxidant composition,the oxidative stress index(OSi)in SP,calcu-lated as total oxidant activity divided by total antioxidant capacity,was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF(0.42±0.06 vs.0.23±0.09 and 0.08±0.00,respectively;P<0.01);this index,in addition,was observed to be correlated to the sperm concentration of each fraction(Rs=0.973;P<0.001).Conclusion While sperm DNA integrity was not found to differ between ejaculate fractions,SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the PSRF.This could be related to the OSi of each fraction. 展开更多
关键词 CHROMATIN condensation DNA integrity Ejaculate fractions PIG Protamination SPERM
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Supersonic expansion and condensation characteristics of hydrogen gas under different temperature conditions
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作者 Xinyue Duan Zeyu Zhang +4 位作者 Ziyuan Zhao Yang Liu Liang Gong Xuewen Cao Jiang Bian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期220-226,共7页
This paper introduced supersonic expansion liquefaction technology into the field of hydrogen liquefaction.The mathematical model for supersonic condensation of hydrogen gas in a Laval nozzle model was established.The... This paper introduced supersonic expansion liquefaction technology into the field of hydrogen liquefaction.The mathematical model for supersonic condensation of hydrogen gas in a Laval nozzle model was established.The supersonic expansion and condensation characteristics of hydrogen gas under different temperature conditions were investigated.The simulation results show that the droplet number rises rapidly from 0 at the nozzle throat as the inlet temperature increases,and the maximum droplet number generated is 1.339×10^(18)kg^(-1)at inlet temperature of 36.0 K.When hydrogen nucleation occurs,the droplet radius increases significantly and shows a positive correlation with the increase in the inlet temperature,and the maximum droplet radii are 6.667×10^(-8)m,1.043×10^(-7)m,and 1.099×10^(-7)m when the inlet temperature is 36.0 K,36.5 K,and 37.0 K,respectively.The maximum nucleation rate decreases with increasing inlet temperature,and the nucleation region of the Laval nozzle becomes wider.The liquefaction efficiency can be effectively improved by lowering the inlet temperature.This is because a lower inlet temperature provides more subcooling,which allows the hydrogen to reach the thermodynamic conditions required for large-scale condensation more quickly. 展开更多
关键词 HYDROGEN LIQUEFACTION SUPERSONIC condensation Laval nozzle Computational fluid dynamics
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Development of functional dye with redshifted absorption based on Knoevenagel condensation at 1-site in phenyl[b]-fused BODIPY
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作者 Tianze Wang Junyi Ren +4 位作者 Dongxiang Zhang Huan Wang Jianjun Du Xin-Dong Jiang Guiling Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第6期349-352,共4页
Integrating ring-fused modification withπ-conjugated extension is an effective approach for designing,synthesizing,and application for novel borondipyrromethene(BODIPY)structures.In this work,based on phenyl[b]-fused... Integrating ring-fused modification withπ-conjugated extension is an effective approach for designing,synthesizing,and application for novel borondipyrromethene(BODIPY)structures.In this work,based on phenyl[b]-fused BODIPY,we made reasonable modification of the methyl group at 1-site to generate dye NBDP.NBDP possessed near-infrared region(NIR)absorption and emission properties,and the intramolecular charge transfer(ICT)resulted in low fluorescence.Whereas,heat energy is evidently released in the presence of light,which can be exploited for intracellular photothermal therapy via the cell apoptosis process,reducing the inflammatory side-effects induced by necrosis.This research provides a crucial foundation for the novel molecule via BODIPY multi-directional alteration and its potential application in anti-tumor phototherapy. 展开更多
关键词 NIR dyes [b]-Fused BODIPY Knoevenagel condensation Photothermal therapy Cell apoptosis
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Controllable Condensation of Aromatics and Its Mechanisms in Carbonization
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作者 Fan Xi Wang Chunlu +3 位作者 Luo Yang Ren Qiang Shen Haiping Long Jun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期34-46,共13页
In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations we... In order to obtain liquefied products with higher yields of aromatic molecules to produce mesophase pitch,a good understanding of the relevant reaction mechanisms is required.Reactive molecular dynamics simulations were used to study the thermal reactions of pyrene,1-methylpyrene,7,8,9,10-tetrahydrobenzopyrene,and mixtures of pyrene with 1-octene,cyclohexene,or styrene.The reactant conversion rates,reaction rates,and product distributions were calculated and compared,and the mechanisms were analyzed and discussed.The results demonstrated that methyl and naphthenic structures in aromatics might improve the conversion rates of reactants in hydrogen transfer processes,but their steric hindrances prohibited the generation of high polymers.The naphthenic structures could generate more free radicals and presented a more obvious inhibition effect on the condensation of polymers compared with the methyl side chains.It was discovered that when different olefins were mixed with pyrene,1-octene primarily underwent pyrolysis reactions,whereas cyclohexene mainly underwent hydrogen transfer reactions with pyrene and styrene,mostly producing superconjugated biradicals through condensation reactions with pyrene.In the mixture systems,the olefins scattered aromatic molecules,hindering the formation of pyrene trimers and higher polymers.According to the reactive molecular dynamics simulations,styrene may enhance the yield of dimer and enable the controlled polycondensation of pyrene. 展开更多
关键词 CARBONIZATION controllable condensation AROMATICS MECHANISMS molecular simulation
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Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring
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作者 D.LEE S.CHANG J.LEE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期819-836,共18页
This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random inputs.The method consists of a gen... This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random inputs.The method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data set.In the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random inputs.This allows for avoiding repeated computations of invariant substructures while generating the input-output data set.Combining substructuring with static condensation further improves the computational efficiency of the reanalysis without losing accuracy.Consequently,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional inputs.The numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs. 展开更多
关键词 forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation SUBSTRUCTURING
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Insertion of pillar[5]arene into Troger’s base-derived porous organic polymer for promoted heterogeneous catalytic performance in Knoevenagel condensation and CO_(2)fixation
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作者 Lu Liu Ziyi Liu +2 位作者 Jingnan Cui Guiling Ning Weitao Gong 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期482-485,共4页
Development of new metal-free heterogeneous catalysts has long been the focus of intense research interest.The integration of multifunctional monomers into the skeletons of porous organic polymers(POPs)provides an eff... Development of new metal-free heterogeneous catalysts has long been the focus of intense research interest.The integration of multifunctional monomers into the skeletons of porous organic polymers(POPs)provides an efficient pathway to achieve this goal.Herein,we rationally designed and successfully prepared a new Troger’s base(TB)-derived POPs by insertion of pillar[5]arene macrocycle as a positively auxiliary group.Combined the both merits of pillar[5]arene macrocycle and TB moiety,the as-prepared polymer was further explored as an effective metal-free heterogeneous catalyst and exhibited promoted catalytic performance in Knoevenagel condensation and CO_(2)conversion.This work provides a new strategy to fabricate metal-free heterogeneous catalysts based on macrocyclic POPs. 展开更多
关键词 arene macrocycle Porous organic polymers Heterogeneous catalytic Knoevenagel condensation CO_(2)fixation
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Reducing Condensation Inside the Photovoltaic(PV)Inverter according to the Effect of Diffusion as a Process of Vapor Transport
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作者 Amal El Berry Marwa M.Ibrahim +1 位作者 A.A.Elfeky Mohamed F.Nasr 《Frontiers in Heat and Mass Transfer》 EI 2024年第4期1189-1207,共19页
A photovoltaic(PV)inverter is a vital component of a photovoltaic(PV)solar system.Photovoltaic(PV)inverter failure can mean a solar system that is no longer functioning.When electronic devices such as photovoltaic(PV)... A photovoltaic(PV)inverter is a vital component of a photovoltaic(PV)solar system.Photovoltaic(PV)inverter failure can mean a solar system that is no longer functioning.When electronic devices such as photovoltaic(PV)inverter devices are subjected to vapor condensation,a risk could occur.Given the amount of moisture in the air,saturation occurswhen the temperature drops to the dewpoint,and condensationmay formon surfaces.Numerical simulation with“COMSOL Software”is important for obtaining knowledge relevant to preventing condensation by using two steps.At first,the assumption was that the device’s water vapor concentration was homogeneous to evaluate the amount of liquid water accumulated on the internal walls of the photovoltaic(PV)inverter box.Second,by considering the effect of external wind velocity onmoisture transport at the air interface to evaluate water vapor transport outdoors and reduce condensation.General factorial designs are utilized for analyzing the nature of the relationship between the vapor condensation response and the variables.Reducing vapor condensation inside the solar inverter by the effect of external wind speed on diffusion as a process of transporting moister air outside the inverter box is the main solution for this problem.During the movement and assessment of the flow of water vapor,the impact of vapor condensation is reduced.The saturation period was determined by using a Boolean saturation indicator.The saturation indicator was set to 1 when saturation was detected(relative humidity greater than or equal to 1)and 0 otherwise.Calculating the flow and dispersion of moist air as a function of wind speed helped solve the problem. 展开更多
关键词 PHOTOVOLTAIC INVERTER failure vapor condensation wind velocity diffusion transport and general factorial
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First and Second Law Analysis of a LiBr-Water Absorption Cycle with Recovering Condensation Heat for Generation
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作者 J.L.Rodríguez-Muñoz J.S.Pacheco-Cedeño +2 位作者 J.F.Ituna-Yudonago J.J.Ramírez-Minguela I.J.González-Hernández 《Frontiers in Heat and Mass Transfer》 EI 2024年第6期1719-1741,共23页
In conventional absorption refrigeration systems(ARS),the heat from the condenser is usually rejected by the environment in place to be used in the system,so recuperating this is a good alternative to enhance the sys... In conventional absorption refrigeration systems(ARS),the heat from the condenser is usually rejected by the environment in place to be used in the system,so recuperating this is a good alternative to enhance the system’s performance.For instance,in this paper,an alternative ARS in which LiBr/Water is used as a refrigerant mixture,where part of condensing heat is recovered via the solution heat recovery generator absorption cycle(HR-ARS)was energy and exergy evaluated.The influence of generator,condenser and evaporator temperatures,as well as the efficiency of the solution heat exchanger on the coefficient of performance,exergy performance and exergy destroyed of the HR-ARS system,were analyzed and compared with the traditional ARS system at the same working conditions.The results showed an increase between 5.8%–6.3%on the COP and 3.7%–9.5%in the exergy efficiency when condenser/absorber temperature was reduced from 40℃ to 30℃.However,when the evaporation temperature rose from 5℃ to 15℃,the COP(coefficient of performance)increased by around 8%,although this could be increased by 2.3%–6.3%if the generator temperature decreases from 100℃ to 80℃.Moreover,the COP and exergetic performance for the HR-ARS is more significant at the lowest generator,condenser and evaporator temperatures,as well as at high efficiency in the solution heat exchanger,in comparison to ARS system.Furthermore,the COP and exergy performance for the HR-ARS system was improved by 2.57%to 3.11%and 0.22%to 0.7%,respectively,while the recovering condensation heat for generation is around 1.51%–3.76%lower than with the ARS.It also was found that for all ranges of evaporator and condenser temperatures,the COP for the HR-ARS system is around 3%higher than that obtained with the ARS at the three different generator temperatures here analyzed,while when the solution heat exchanger effectiveness was increased from 0.7–1.0,the total exergy destruction for the HR-ARS resulted be 3.24%–5.01%smaller than the ARS system.Finally,it can be concluded that the components with the most exergy destroyed in the systems(80%to 94%)are the generator and absorber. 展开更多
关键词 Absorption refrigeration system recovery condensation heat energy and exergy analysis LiBr-H_(2)O
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Finite-Time Thermodynamic Simulation of Circulating Direct Condensation Heat Recovery on Chillers
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作者 Zhixin Yang Feihu Chen +1 位作者 Liping Wang Guangcai Gong 《Journal of Power and Energy Engineering》 2024年第1期1-14,共14页
A time series model is used in this paper to describe the progress of circulating direct condensation heat recovery of the compound condensing process (CCP) which is made of two water cooling condensing processes in s... A time series model is used in this paper to describe the progress of circulating direct condensation heat recovery of the compound condensing process (CCP) which is made of two water cooling condensing processes in series for a centrifugal chiller in the paper. A finite-time thermodynamics method is used to set up the time series simulation model. As a result, an upper bound of recoverable condensation heat for the compound condensing process is obtained which is in good agreement with experimental result. And the result is valuable and useful to optimization design of condensing heat recovery. 展开更多
关键词 condensation Heat Recovery Compound Condensing Process Time Series Finite-Time Thermodynamics
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New Strategy Leverages Lignin Condensation for Biomass Utilization
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作者 WANG Feng 《Bulletin of the Chinese Academy of Sciences》 2024年第2期107-108,共2页
There is an old saying in the biorefining industry that“You can make anything from lignin except money.”This bio-based compound is abundant and full of potential,but commercializing it remains a challenge.This may n... There is an old saying in the biorefining industry that“You can make anything from lignin except money.”This bio-based compound is abundant and full of potential,but commercializing it remains a challenge.This may no longer be the case soon with an innovative approach by chemists from the Dalian Institute of Chemical Physics(DICP)of the Chinese Academy of Sciences and their colleagues to harness lignin condensation–often considered a nuisance–for efficient utilization of lignocellulose. 展开更多
关键词 condensation condensation BIOMASS
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