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Ferrihydrite transformation impacted by coprecipitation of lignin:Inhibition or facilitation?

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Journal of Environmental Sciences 2024年第5期139卷 23-33页

作者： Lin Liu Zhihui Yang Weichun Yang Wen Jiang Qi Liao Mengying Si Feiping Zhao School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution(CNERC-CTHMP) Changsha 410083China

Lignin is a common soil organic matter that is present in soils,but its effect on the transformation of ferrihydrite(Fh)remains unclear.Organic matter is generally assumed to inhibit Fh transformation.However,lignin can reduce Fh to Fe(Ⅱ),in which Fe(Ⅱ)-catalyzed Fh transformation occurs.Herein,the effects of lignin on Fh transformation were investigated at 75℃ as a function of the lignin/Fh mass ratio(0-0.2),pH(4-8)and aging time(0-96 hr).The results of Fh-lignin samples(mass ratios=0.1)aged at different pH values showed that for Fh-lignin the time of Fh transformation into secondary crystalline minerals was significantly shortened at pH 6 when compared with pure Fh,and the Fe(Ⅱ)-accelerated transformation of Fh was strongly dependent on pH.Under pH 6,at low lignin/Fh mass ratios(0.05-0.1),the time of secondary mineral formation decreased with increasing lignin content.For high lignosulfonate-content material(lignin:Fh=0.2),Fh did not transform into secondary minerals,indicating that lignin content plays a major role in Fh transformation.In addition,lignin affected the pathway of Fh transformation by inhibiting goethite formation and facilitating hematite formation.The effect of coprecipitation of lignin on Fh transformation should be useful in understanding the complex iron and carbon cycles in a soil environment.

关键词： Ferrihydrite transformation Lignin Hematite Goethite Fe(Ⅱ)-catalyzed Reactive Fe(Ⅲ)species

Degeneration and rejuvenation of shape memory effect associated with the precipitation of coherent nano-particles in a Co-Ni-Si shape memory alloy

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Journal of Materials Science & Technology 2021年第17期76卷 150-155页

作者： Huabei Peng Dian Wang Qi Liao Yuhua Wen School of Mechanical Engineering Sichuan UniversityChengdu 610065China

In a solution treated Co-20Ni-6Si shape memory alloy,coherent nano-particles were precipitated after annealing at 873 K for 1 min,but the shape memory effect almost vanished.It is attributed to that the coherent nano-particles not only suppressed the stress-induced face-centered cubic to close-packed hexagonal martensite transformation but also damaged the crystallographic reversibility of reverse martensite transformation.After further annealing at 1073 K for 1 min,the shape memory effect was rejuvenated owing to the dissolution of nano-particles.Besides,the recovery strain significantly increased to5.1%from the solution treatment of 3.1%after annealing at 1073 K for 1 min.

关键词： Shape memory alloys Martensitic phase transformation Defects Coherent nano-particles

Synthesis of High Molecular Weight Polyethylene and E-MA Copolymers Using Iminopyridine Ni(Ⅱ) and Pd(Ⅱ) Complexes Containing a Flexible Backbone and Rigid Axial Substituents

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Chinese Journal of Polymer Science 2023年第2期41卷 233-239页

作者： Yu-Dan liao qi Cai Sheng-Yu Dai School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu241000China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China

Suppressing the chain transfer reactions during polymerization in late-transition metal-catalyzed olefin polymerization systems is the key to obtaining high molecular weight polyolefin materials. In this work, two efficient strategies(“sandwich” and rotation-restricted strategies)to retard chain transfer reactions in ethylene(co)polymerization were employed for the iminopyridyl system. Herein, a family of iminopyridyl Ni(Ⅱ)and Pd(Ⅱ) complexes with a flexible backbone and rigid axial bulky aryl substituents were designed, synthesized and characterized. In ethylene polymerization, the iminopyridyl Ni(Ⅱ) and Pd(Ⅱ) catalysts using the two strategies exhibited reasonable activities and generated highly branched polyethylenes with high molecular weights, where catalysts with dibenzosuberyl substituents exhibited significantly higher activities and produced higher molecular weight polyethylene than catalysts with 8-arylnaphthalenyl substituent. A similar trend of activities and molecular weights was also found in the copolymerization of ethylene with MA using the Pd(Ⅱ) catalysts. Moreover, highly branched E-MA copolymers with moderate to high molecular weights and high incorporation ratios(up to 17.4 mol%) were generated with the two Pd(Ⅱ) catalysts. Most interestingly, as compared with the dibenzhydryl Ni(Ⅱ) and Pd(Ⅱ) catalysts, the catalysts using the two strategies exhibited a superior ability to retard the chain transfer reactions and generated polymers and copolymers with 1-2 orders of magnitude higher molecular weights during ethylene(co)polymerization.

关键词： Ni(Ⅱ)and Pd(Ⅱ) Suppressing chain transfer High molecular weight Ethylene(co)polymerization

Primary logistics planning of oil products under the imbalance of supply and demand

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Petroleum Science 2022年第4期19卷 1915-1925页

作者： Rui qiu Yong-Tu Liang Qi Liao Ying-qi Jiao Bo-Hong Wang Yi Guo Hao-Ran Zhang National Engineering Laboratory for Pipeline Safety/Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum-BeijingFuxue Road No.18Changping DistrictBeijing102249PR China School of Petrochemical Engineering and Environment Zhejiang Ocean UniversityZhoushan316022China Sustainable Process Integration Laboratory–SPIL NETME CentreFaculty of Mechanical EngineeringBrno University of Technology–VUT BrnoTechnická2896/261669BrnoCzech Republic Oil&Gas Pipeline Control Center PipeChinaDongtucheng Road No.5Chaoyang DistrictBeijing100013PR China Center for Spatial Information Science The University of Tokyo5-1-5 KashiwanohaKashiwa-shiChiba277-8568Japan

This paper intends to complete the primary logistics planning of oil products under the imbalance of supply and demand. An integrated mathematical programming model is developed to simultaneously find the balance between supply and demand, and optimize the logistics scheme. The model takes minimum logistics cost and resource adjustment cost as the objective function, and takes supply and demand capacity, transportation capacity, mass balance, and resource adjustment rules as constraints.Three adjustment rules are considered in the model, including resource adjustment within oil suppliers,within oil consumers, and between oil consumers. The model is tested on a large-scale primary logistics of a state-owned petroleum enterprise, involving 37 affiliated refineries, 31 procurement departments,286 market depots and dedicated consumers. After the unified optimization, the supply and demand imbalance is eased by 97% and the total cost is saved by 7%, which proves the effectiveness and applicability of the proposed model.

关键词： Oil product logistics Supply and demand imbalance Petroleum enterprise Resource adjustment Mathematical Programming model

Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： Zhao-yang Yin qi-chi Le Yan-chao Jiang Da-zhi Zhao qi-yu liao qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy melt.The effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in detail.Additionally,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct ultrasounds.As a result,various acoustic pressure distributions and cavitation regions are obtained.The spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical rods.Increasing the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution pattern.The acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

Chemical constituents from aerial parts of Scoparia dulcis

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Chinese Herbal Medicines 2023年第1期15卷 151-154页

作者： Yingbo Yang Zhuzhen Han Tong Tian Qi Liao Jiaran Geng Ying Xiao The SATCM Key Laboratory for New Resources&Quality Evaluation of Chinese Medicine Institute of Chinese Materia MedicaShanghai University of Traditional Chinese MedicineShanghai 201203China Jiangsu Kanion Pharmaceutical Co. Ltd.Lianyungang 222000China

Objective: To study the chemical constituents from the aerial parts of Scoparia dulcis.Methods: Various chromatographic techniques were used to separate the constituents and their structures were elucidated using spectroscopic methods and by comparing their data to those reported in the literatures. The α-glucosidase inhibitory activity assay was used to identify potential α-glucosidase inhibitors.Results: Nine compounds were isolated from the aerial parts of S. dulcis. Their structures were identified as Scoparic zolone(1),(2S)-2,7-dihydroxy-2H-1,4-benzoxazin-3(4H)-one(2),(2R)-7-hydroxy-2H-1,4-benzoxazin-3(4H)-one-2-O-β-D-glucopyranoside(3),(2R)-7-methoxy-2H-1,4-benzoxazin-3(4H)-one-2-O-β-D-glucopyranoside(4),(2S)-7-hydroxy-2H-1,4-benzoxazin-3(4H)-one-2-O-β-D-glucopyranoside(5),6-methoxy-benzoxazolin-2(3H)-one(6), 4-acetonyl-3,5-dimethoxy-p-quinol(7), zizyvoside I(8), and3,4-dihydroxy benzeneacetic acid(9). Compound 2 showed the potent α-glucosidase inhibitory activity with an IC50value of(132.8 ± 11.5) μmol/L, which is 28-fold higher than the positive control acarbose.Conclusion: Compound 1 is a new natural product. Compounds 2 and 9 have not been reported in Scoparia before. Compounds 3, 5, 7, 8 are isolated from Scrophulariaceae for the first time.

关键词： alkaloids chemical constituents α-glucosidase inhibitory activity Scoparia dulcis L.

Tumor-microenvironment activated programmable synergistic cancer therapy by bioresponsive rare-earth nanocomposite

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Journal of Rare Earths 2022年第9期40卷 1399-1406,I0003页

作者： qi Jia Xin Han Yuxin Liu Xianquan liao Jing Zhou Capital Normal University Beijing 100048China

Synergistic chemotherapy-photothermal therapy(CT-PTT)can improve the cancer treatment efficacy,but its treatment effect is still limited by factors such as targeting efficiency and treatment sequence.Herein,a H_(2)S-responsive metal organic frameworks(MOFs)coated rare-earth nanocomposite(csEr@-MOF)was constructed and loaded with a chemotherapeutic drug(DOX)and a heat shock protein(HSP)inhibitor(Shepherdin).As the drug-loaded csEr@MOF reaches the H_(2)S-riched colorectal tumor region,based on the reaction between H_(2)S and MOF,Shepherdin is released for inhibiting the function of HSPs,the generated CuS is used for PTT and DOX is released for CT.Through being monitored by ratiometric imaging of rare-earth nanocomposite,it is possible to perform the precise treatment timing for PTT.With the help of Shepherdin,the treatment effect of PTT was enhanced.Therefore,programmable CT-PTT synergistic cancer therapy activated by a single H_(2)S trigger is achieved in vitro and in vivo.This work provides new ideas for designing tumor microenvironment-responsive therapeutic agents for programmable synergistic therapy with better targeting and therapeutic efficiency.

关键词： Rare-earth nanocomposite Tumor microenvironment Hydrogen sulfide Synergistic therapy Programmable therapy

Characteristics of dust distributions and dust control measures around road-header drivers in mining excavation roadways

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Particuology 2021年第5期19卷 268-275页

作者： Shengyong Hu Yang Gao Guorui Feng Yisheng Huang He Shaoa Qi Liao Fei Hu College of Safety and Emergency Management Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Green Mining Engineering Technology Research Center of Shanxi Province Taiyuan 030024China

In the present study,a numerical simulation method was adopted in order to examine the characteristics of dust dispersion during continuous dust release periods(CRP)and stop dust release periods(SRP).The purpose was to analyze the dust distributions and migration actions around road-header drivers in excavation roadways,and then determine effective dust control measures for underground coal mines.This study’s simulation results showed that the dust concentrations continuously increased,and then gradually reached a stability level during the CRP.During that time,the locations of the drivers were always at the intersection of the original migration dust and the backflow dust,and the drivers were invaded by these two strands dust.However,during the SRP,the dust concentrations gradually decreased under the actions of the roadway ventilation.Besides,obvious backflow phenomena were observed around the road-header during the SRP.The locations of the drivers were still within the backflow paths of the high dust concentrations.At the present time,dust separation and extraction systems have been implemented in coal mines,including vacuuming and air knife devices,which are designed to control the dust around the road-header drivers.The field applications of these systems were conducted in the 26 mechanized excavation faces of the Zhangcun Coal Mine.The results revealed that the use of these dust removal systems could effectively reduce the dust concentrations around the road-header drivers.In the present study,the dust removal rates during the CRP and SRP were determined to reach up to 88.7% and 94.6%,respectively.Therefore,the results of this research study provided effective theoretical guidance of the characteristics of dust distributions in coal mines,and introduced effective control methods for the hazardous dust concentrations around road-header drivers during the excavation process.

关键词： Excavation roadway Road-header driver Dust distribution Dust control Numerical simulation

Scenario Generation for Cooling,Heating,and Power Loads Using Generative Moment Matching Networks

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1730-1740页

作者： Wenlong liao Yusen Wang Yuelong Wang Kody Powell qi Liu Zhe Yang Department of Energy Technology Aalborg UniversityAalborg 9220Denmark School of Electrical Engineering and Computer Science KTH Royal Institute of TechnologyStockholmSE-10044Sweden State Grid Tianjin Chengxi Electric Power Supply Branch Tianjin 300100China Department of Chemical Engineering University of UtahUT 84112America Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China

Scenario generations of cooling,heating,and power loads are of great significance for the economic operation and stability analysis of integrated energy systems.In this paper,a novel deep generative network is proposed to model cooling,heating,and power load curves based on generative moment matching networks(GMMNs)where an auto-encoder transforms highdimensional load curves into low-dimensional latent variables and the maximum mean discrepancy represents the similarity metrics between the generated samples and the real samples.After training the model,the new scenarios are generated by feeding Gaussian noises to the scenario generator of the GMMN.Unlike the explicit density models,the proposed GMMN does not need to artificially assume the probability distribution of the load curves,which leads to stronger universality.The simulation results show that the GMMN not only fits the probability distribution of multiclass load curves very well,but also accurately captures the shape(e.g.,large peaks,fast ramps,and fluctuation),frequency-domain characteristics,and temporal-spatial correlations of cooling,heating,and power loads.Furthermore,the energy consumption of generated samples closely resembles that of real samples.

关键词： Deep learning generative moment matching networks integrated energy systems scenario generations