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Molecular diffusion in ternary poly(vinyl alcohol) solutions

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 1003-1016 doi: 10.1007/s11705-021-2121-3

摘要： The diffusion kinetics of a molecular probe—rhodamine B—in ternary aqueous solutions containing poly(vinyl alcohol), glycerol, and surfactants was investigated using fluorescence correlation spectroscopy and dynamic light scattering. We show that the diffusion characteristics of rhodamine B in such complex systems is determined by a synergistic effect of molecular crowding and intermolecular interactions between chemical species. The presence of glycerol has no noticeable impact on rhodamine B diffusion at low concentration, but significantly slows down the diffusion of rhodamine B above 3.9% (w/v) due to a dominating steric inhibition effect. Furthermore, introducing surfactants (cationic/nonionic/anionic) to the system results in a decreased diffusion coefficient of the molecular probe. In solutions containing nonionic surfactant, this can be explained by an increased crowding effect. For ternary poly(vinyl alcohol) solutions containing cationic or anionic surfactant, surfactant–polymer and surfactant–rhodamine B interactions alongside the crowding effect of the molecules slow down the overall diffusivity of rhodamine B. The results advance our insight of molecular migration in a broad range of industrial complex formulations that incorporate multiple compounds, and highlight the importance of selecting the appropriate additives and surfactants in formulated products.

关键词： fluorescence correlation spectroscopy     poly(vinyl alcohol)     anomalous diffusion     crowding effects     dynamic light scattering     binding effects     rhodamine B    

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Temporal variation of PM-associated health effects in Shijiazhuang, Hebei

《环境科学与工程前沿（英文）》 2021年 第15卷 第5期 doi: 10.1007/s11783-020-1376-0

摘要：

•Annual mean PM2.5 in Shijiazhuang were 87, 95, and 82 µg/m3 in 2015–2017.

关键词： PM2.5     Health effects     Integrated exposure-response model     Shijiazhuang    

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Synergistic effects and kinetics analysis for co-pyrolysis of vacuum residue and plastics

《化学科学与工程前沿（英文）》 2024年 第18卷 第5期 doi: 10.1007/s11705-024-2414-4

摘要： This study utilized a thermogravimetric analyzer to assess the thermal decomposition behaviors and kinetics properties of vacuum residue (VR) and low-density polyethylene (LDPE) polymers. The kinetic parameters were calculated using the Friedman technique. To demonstrate the interactive effects between LDPE and VR during the co-pyrolysis process, the disparity in mass loss and mass loss rate between the experimental and calculated values was computed. The co-pyrolysis curves obtained through estimation and experimentation exhibited significant deviations, which were influenced by temperature and mixing ratio. A negative synergistic interaction was observed between LDPE and VR, although this inhibitory effect could be mitigated or eliminated by reducing the LDPE ratio in the mixture and increasing the co-pyrolysis temperature. The co-pyrolysis process resulted in a reduction in carbon residue, which could be attributed to the interaction between LDPE and the heavy fractions, particularly resin and asphaltene, present in VR. These findings align with the pyrolysis behaviors exhibited by the four VR fractions. Furthermore, it was observed that the co-pyrolysis process exhibited lower activation energy as the VR ratio increased, indicating a continuous enhancement in the reactivity of the mixed samples during co-pyrolysis.

关键词： co-pyrolysis     heavy residual oil     polyethylene     thermogravimetric analysis     synergistic effects    

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Synergistic effects of sodium hypochlorite disinfection and iron-oxidizing bacteria on early corrosion

《环境科学与工程前沿（英文）》 2022年 第16卷 第6期 doi: 10.1007/s11783-021-1506-3

摘要：

• The early corrosion process in the cast iron pipes was investigated.

关键词： Cast iron pipe corrosion     Drinking water distribution systems     Chlorine disinfection     Iron-oxidizing bacteria     Coupling effects    

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Metal size effects over metal/zeolite bifunctional catalysts in the selective hydroalkylation of benzene

《化学科学与工程前沿（英文）》 2024年 第18卷 第4期 doi: 10.1007/s11705-024-2406-4

摘要： Bifunctional metal/zeolite materials are some of the most suitable catalysts for the direct hydroalkylation of benzene to cyclohexylbenzene. The overall catalytic performance of this reaction is strongly influenced by the hydrogenation, which is dependent on the metal sizes. Thus, systematically investigating the metal size effects in the hydroalkylation of benzene is essential. In this work, we successfully synthesized Ru and Pd nanoparticles on Sinopec Composition Materials No.1 zeolite with various metal sizes. We demonstrated the size-dependent catalytic activity of zeolite-supported Ru and Pd catalysts in the hydroalkylation of benzene, which can be attributed to the size-induced hydrogen spillover capability differences. Our work presents new insights into the hydroalkylation reaction and may open up a new avenue for the smart design of advanced metal/zeolite bi-functional catalysts.

关键词： size effects     bifunctional catalysts     metal/zeolite     hydroalkylation    

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Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of

《结构与土木工程前沿（英文）》 2022年 第16卷 第1期   页码 99-116 doi: 10.1007/s11709-021-0799-4

摘要： In this study, bituminous binder was modified with Cocamide Diethanolamide chemical, a non-ionic surfactant, and the physical and rheological properties of modified binders were investigated. In addition, Cocamide Diethanolamide has been used for the first time to modify bituminous binder, and this situation makes the study distinctive. Bituminous binder was modified more than once with the chemical by changing modification parameters and using certain additive ratios (1%, 3%, and 5%). The effects of different modification parameters and chemical additive on modified samples were investigated with conventional bitumen tests (softening point, penetration, ductility) and Superpave tests (rotational viscometer, rolling thin film oven test, pressure aging vessel, dynamic shear rheometer, bending beam rheometer). In addition, the structural characteristics of the reference binder and modified samples were examined by X-ray diffraction, Fourier Transform Infrared Spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The examinations showed that Cocamide Diethanolamide softens bituminous binder and lowers processing temperatures. In addition, compared to reference binder, rutting resistances of modified bituminous binders decreased with the increase of additive ratio. However, modification with Cocamide Diethanolamide increased the resistance to fatigue cracks and thermal cracks.

关键词： Cocamide Diethanolamide     bitumen modification     rheology     Superpave tests    

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Protective effects of lignin fractions obtained from grape seeds against bisphenol AF neurotoxicity viaantioxidative effects mediated by the Nrf2 pathway

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 976-989 doi: 10.1007/s11705-022-2237-0

摘要： Lignin exhibits antioxidative and various other biological properties. However, its neuroprotection capability has rarely been studied. In this study, three types of lignin with different structures were prepared from grape seeds by using different isolation techniques. The antioxidative and neuroprotective effects of the lignin fractions were evaluated with the apoptosis model of murine neuroectodermal (NE-4C) neural stem cells stimulated with bisphenol AF. The results demonstrated that the half maximal inhibitory concentration for scavenging 2,2-diphenyl-1-picrylhydrazyl with water-soluble lignin (L-W, 58.19 μg·mL–1) was lower than those of lignin in the autohydrolyzed residue of grape seeds (84.27 μg·mL–1) and original lignin in grape seeds (99.44 μg·mL–1). BPAF exposure had negative effects on the reactive oxygen species, malondialdehyde content, and superoxide dismutase and glutathione peroxidase activities in NE-4C cells, which can be reversed by using the prepared lignin to reduce oxidative stress. An immunofluorescence assay demonstrated that grape seed lignin induced protective effects on BPAF-injured NE-4C cells via the nuclear factor erythroid 2-related Factor 2 pathway. In addition, correlational analyses showed that lignin (L-W) with lower molecular weights and noncondensed phenolic hydroxyl group content and higher contents of COOH groups effectively prevented cell apoptosis, scavenged reactive oxygen species, and ensured protection from nerve injury. This study demonstrated that grape seed lignin can be used as a neuroprotective agent and serves as a demonstration of active lignin production from grape seed waste.

关键词： grape seed lignin     structure     antioxidant     NE-4C cells     neuroprotection    

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Quorum sensing regulation methods and their effects on biofilm in biological waste treatment systems:

《环境科学与工程前沿（英文）》 2022年 第16卷 第7期 doi: 10.1007/s11783-021-1495-2

摘要：

• Quorum sensing enhancement and inhibition methods are summarized.

关键词： Quorum sensing     Biological waste treatment     Biofilm formation    

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Seismic effects on reinforcement load and lateral deformation of geosynthetic-reinforced soil walls

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 1001-1015 doi: 10.1007/s11709-021-0734-8

摘要： Current design methods for the internal stability of geosynthetic-reinforced soil (GRS) walls postulate seismic forces as inertial forces, leading to pseudo-static analyses based on active earth pressure theory, which yields unconservative reinforcement loads required for seismic stability. Most seismic analyses are limited to the determination of maximum reinforcement strength. This study aimed to calculate the distribution of the reinforcement load and connection strength required for each layer of the seismic GRS wall. Using the top-down procedure involves all of the possible failure surfaces for the seismic analyses of the GRS wall and then obtains the reinforcement load distribution for the limit state. The distributions are used to determine the required connection strength and to approximately assess the facing lateral deformation. For sufficient pullout resistance to be provided by each reinforcement, the maximum required tensile resistance is identical to the results based on the Mononobe–Okabe method. However, short reinforcement results in greater tensile resistances in the mid and lower layers as evinced by compound failure frequently occurring in GRS walls during an earthquake. Parametric studies involving backfill friction angle, reinforcement length, vertical seismic acceleration, and secondary reinforcement are conducted to investigate seismic impacts on the stability and lateral deformation of GRS walls.

关键词： geosynthetics     reinforced soil     retaining walls     seismic performance    

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Effects of manufactured nanomaterials on algae: Implications and applications

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1554-3

摘要：

● Summary of positive and negative effects of MNMs on algae.

关键词： Manufactured nanomaterials     Algae     Mechanisms     Effects     Implications     Applications    

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Modeling radiative effects of haze on summer-time convective precipitation over North China: a case study

Xuying WANG, Bin ZHANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0840-3

摘要： We modeled the impact of haze radiative effects on precipitation in North China. Shortwave heating induced by haze radiative effects would reduce heavy rainfalls. Convection was the key factor that whether precipitation was enhanced or suppressed. Precipitation was often suppressed where CAPE, RH and updraft velocities were high. The impact of haze radiative effect on summertime 24-h convective precipitation over North China was investigated using WRF model (version 3.3) through model sensitivity studies between scenarios with and without aerosol radiative effects. The haze radiative effect was represented by incorporating an idealized aerosol optical profile, with AOD values around 1, derived from the aircraft measurement into the WRF shortwave scheme. We found that the shortwave heating induced by aerosol radiative effects would significantly reduce heavy rainfalls, although its effect on the post-frontal localized thunderstorm precipitation was more diverse. To capture the key factors that determine whether precipitation is enhanced or suppressed, model grids with 24-h precipitation difference between the two scenarios exceeding certain threshold (>30 mm or<-30 mm) were separated into two sets. Analyses of key meteorological variables between the enhanced and suppressed regimes suggested that atmospheric convection was the most important factor that determined whether precipitation was enhanced or suppressed during summertime over North China. The convection was stronger over places with precipitation enhancement over 30 mm. Haze weakened the convection over places with precipitation suppression exceeding 30 mm and caused less water vapor to rise to a higher level and thus further suppressed precipitation. The suppression of precipitation was often accompanied with relatively high convective available potential energy (CAPE), relative humidity (RH) and updraft velocities.

关键词： Haze     Aerosol radiative effects     Convective precipitation    

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Interactive effects of high-speed rail on nodal zones in a city: exploratory study on China

Guo LIU, Kunhui YE

《工程管理前沿（英文）》 2019年 第6卷 第3期   页码 327-335 doi: 10.1007/s42524-019-0051-2

摘要： The arrival of the high-speed rail (HSR) era has accelerated the pace of urban development, but its broad socioeconomic impact remains subject to intense debates. This research aims to propose a model for measuring the impact of HSR operation on HSR stations and the surrounding areas, which this research call the HSR-based nodal zone (HNZ). The proposed model is composed of two variables (i.e., transportation situation and vitality) and three subsystems (i.e., economic, societal, and environmental). Data were collected in China through questionnaire survey. Results indicate that the effects of HSR operation on HNZ are multidimensional, transportation vitality has an intermediary role in the effects, and the effects on the physical environment are negative. This study presents an early examination of the impact of HSR operation on the HSR stations and relevant areas and contributes new evidence to academic debates on the contribution of HSR to urban development. Accordingly, urban development policies should be built on the mechanism of HSR in driving the growth of HNZ.

关键词： high-speed rail     nodal zone     interactive effects     sustainable urbanization     China    

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Higher-order mode effects on the seismic performance of tall piers

Zhongguo GUAN, Jianzhong LI, Yan XU, Hao LU

《结构与土木工程前沿（英文）》 2011年 第5卷 第4期   页码 496-502 doi: 10.1007/s11709-011-0131-9

摘要： A comprehensive analysis was conducted to investigate the seismic performance of a typical tall bridge pier through incremental dynamical analysis (IDA). The effect of higher-order modes was studied specifically. The results showed that higher-order modes significantly contributed to the structural seismic response and should not be neglected. Including these modes resulted in an additional hinge midway up the pier. No plastic hinge would occur at this location for conventional bridge piers. Higher-order modes also led to an out-of-phase response between the hinge rotation at the pier bottom and the displacement at the top. This means that the displacement-based seismic design method cannot correctly predict the mechanical state of the critical hinge and therefore is not suitable for use in the seismic design of tall piers. Mistakenly using the displacement-based seismic design method for tall piers may result in a seriously unsafe condition.

关键词： tall bridges     higher-order mode effects     incremental dynamic analysis    

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Beneficial effects of preventive cholecystectomy in patients with hepatic cancer

LIU Anzhong, LI Jun, HUA Huwei

《医学前沿（英文）》 2008年 第2卷 第2期   页码 139-142 doi: 10.1007/s11684-008-0026-x

摘要： There is no conclusive answer to the question whether excising gall bladder is helpful to the patient with hepatic cancer. The survival rate of patients with hepatic cancer for more than two years has been increased, and the incidence of complications of cholecystitis and gall stone are relatively higher among these patients, which may seriously complicate treatment of advanced hepatic cancer and decrease quality of life. The researchers conducted a prospective clinical investigation from 2002 to 2006 to assess the clinical significance of preventive cholecystectomy in patients with hepatic cancer. One hundred and eighteen cases of postoperative patients with hepatic cancer, who survived for more than two years, were followed up. Based on whether cholecystectomy was performed, the patients were divided into two groups including 48 cases with cholecystectomy and 70 cases with cholecyst reserved. The two-year morbidity of gall stone and morbidity of pain in the right upper abdomen of cholecyst reservation group were 54.29% and 68.57%, respectively, obviously higher than 0.00% and 20.83% of cholecystectomy group. Mainly for those treated with transcatheter arterial chemo-embolization, the morbidity of gall stone was 86.67% ( < 0.01). Therefore, preventive cholecystectomy is strongly recommended during hepatectomy to decrease the incidence of chronic cholecystitis and gall stone, especially for those whose chemotherapy and embolization will be carried out through hepatic artery and portal vein.
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Bile acids and their effects on diabetes

Cynthia Rajani, Wei Jia

《医学前沿（英文）》 2018年 第12卷 第6期   页码 608-623 doi: 10.1007/s11684-018-0644-x

摘要： Diabetes is a widespread, rapidly increasing metabolic disease that is driven by hyperglycemia. Early glycemic control is of primary importance to avoid vascular complications including development of retinal disorders leading to blindness, end-stage renal disease, and accelerated atherosclerosis with a higher risk of myocardial infarction, stroke and limb amputations. Even after hyperglycemia has been brought under control, “metabolic memory,” a cluster of irreversible metabolic changes that allow diabetes to progress, may persist depending on the duration of hyperglycemia. Manipulation of bile acid (BA) receptors and the BA pool have been shown to be useful in establishing glycemic control in diabetes due to their ability to regulate energy metabolism by binding and activating nuclear transcription factors such as farnesoid X receptor (FXR) in liver and intestine as well as the G-protein coupled receptor, TGR5, in enteroendocrine cells and pancreatic -cells. The downstream targets of BA activated FXR, FGF15/21, are also important for glucose/insulin homeostasis. In this review we will discuss the effect of BAs on glucose and lipid metabolism and explore recent research on establishing glycemic control in diabetes through the manipulation of BAs and their receptors in the liver, intestine and pancreas, alteration of the enterohepatic circulation, bariatric surgery and alignment of circadian rhythms.

关键词： bile acids     metabolic memory     diabetes     circadian rhythm     bariatric surgery    

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标题 作者 时间 类型 操作

Molecular diffusion in ternary poly(vinyl alcohol) solutions

期刊论文

Temporal variation of PM-associated health effects in Shijiazhuang, Hebei

期刊论文

Synergistic effects and kinetics analysis for co-pyrolysis of vacuum residue and plastics

期刊论文

Synergistic effects of sodium hypochlorite disinfection and iron-oxidizing bacteria on early corrosion

期刊论文

Metal size effects over metal/zeolite bifunctional catalysts in the selective hydroalkylation of benzene

期刊论文

Investigation of effects of Cocamide Diethanolamide chemical on physical and rheological properties of

期刊论文

Protective effects of lignin fractions obtained from grape seeds against bisphenol AF neurotoxicity viaantioxidative effects mediated by the Nrf2 pathway

期刊论文

Quorum sensing regulation methods and their effects on biofilm in biological waste treatment systems:

期刊论文

Seismic effects on reinforcement load and lateral deformation of geosynthetic-reinforced soil walls

期刊论文

Effects of manufactured nanomaterials on algae: Implications and applications

期刊论文

Modeling radiative effects of haze on summer-time convective precipitation over North China: a case study

Xuying WANG, Bin ZHANG

期刊论文

Interactive effects of high-speed rail on nodal zones in a city: exploratory study on China

Guo LIU, Kunhui YE

期刊论文

Higher-order mode effects on the seismic performance of tall piers

Zhongguo GUAN, Jianzhong LI, Yan XU, Hao LU

期刊论文

Beneficial effects of preventive cholecystectomy in patients with hepatic cancer

LIU Anzhong, LI Jun, HUA Huwei

期刊论文

Bile acids and their effects on diabetes

Cynthia Rajani, Wei Jia

期刊论文