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Journal of Environmental Sciences 2021年第4期33卷 352-362页

作者： hui yu Yongfeng Zhu Aiping hui Fangfang yang Aiqin Wang Key Laboratory of Clay Mineral Applied Research of Gansu Province Center of Eco-material and Green ChemistryLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The aqueous foam template without any solvent and only using the particles stabilizer has attracted much attention for preparation of the porous adsorbents.Herein,a novel porous adsorbent was fabricated via thermal-initiated polymerization of Pickering aqueous foams,which was stabilized by the natural sepiolite(Sep)and pine pollen,and utilized for the removal of antibiotic from aqueous solution.The stabilizing mechanism of Pickering aqueous foam of that the Sep was modified with the leaching substance from pine pollen and arranged orderly around the bubble to form a dense"shell"structure was revealed.The adsorbents possessed the hierarchical porous structure and excellent adsorption performance for antibiotic of chlorotetracycline hydrochloride(CTC)and tetracycline hydrochloride(TC).The equilibrium adsorption capacities of CTC and TC were achieved with 465.59 and 330.59 mg/g within 60 min at 25℃,respectively.The adsorption process obeyed Langmuir model and pseudo-second-order adsorption kinetic model.This work provided eco-friendly approach for fabricate porous adsorbents for wastewater treatment.

关键词： Porous adsorbent Adsorption Antibiotic Pickering aqueous foams Pollen Sepiolite

Effect of prior martensite on bainite transformation and microstructure of high-carbon nano-bainitic steel

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Journal of Iron and Steel Research(International) 2022年第4期29卷 647-654页

作者： Xin-pan yu hui-bin Wu yang Gu Rui yuan You-you Zhang yu-hui Feng Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

Bainite transformation kinetics,microstructure,and mechanical properties were comparably investigated by X-ray diffraction,scanning electron microscopy,electron backscatter diffraction,transmission electron microscopy observation,and tensile and impact tests for two treatments:with and without quenching before isothermal bainite transformation at 300°C.Both the incubation time and growth stage of bainite transformation are accelerated by the introduction of prior martensite,especially the former.In addition,the bainite microstructure around the prior martensite is refined and shows a similar orientation with the martensite due to the strain field caused by the existence of prior martensite.The finer bainite microstructure and prior martensite improve the strength and hardness of the high-carbon nano-bainitic steel.Although the presence of prior martensite and low misorientation relationship between the martensite and the adjacent bainite microstructure are prejudicial to impact toughness,the nanoscale bainite microstructure can inhibit the crack propagation and then improve the impact toughness of the high-carbon nano-bainitic steel.

关键词： Nano-bainitic steel Prior martensite Transformation kinetics Microstructure Mechanical property

Preparation of Fe_(3)Si and FeSi intermetallic compounds from copper slag by electrochemical method

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Journal of Iron and Steel Research(International) 2023年第2期30卷 305-316页

作者： hui Li Chao-long Xue yu yang Jing-long Liang Key Laboratory of Ministry of Education for Modern Metallurgy Technology and College of Metallurgy and Energy North China University of Science and TechnologyTangshan063009HebeiChina Comprehensive Testing and Analyzing Center North China University of Science and TechnologyTangshan063009HebeiChina

Fe_(3)Si and FeSi intermetallic compounds were prepared by CaCl_(2)-NaCl melt electrolysis at 800℃from the non-magnetic copper slag compound.The phase transition of the cathode particles with different electrolysis voltages and durations was investigated by X-ray fluorescence spectroscopy,inductively coupled plasma spectroscopy,X-ray diffraction,and scanning electron microscopy.The results showed that Fe_(3)Si and FeSi intermetallic compounds can be obtained by one-step electrolysis for 10 h at 3.2 V and two-step electrolysis of 2.5 V for 4 h and 3.2 V for 6 h.However,the current efficiency increased from 31.70%of one-step electrolysis to 39.87%of two-step electrolysis.The formation of Fe_(3)Si and FeSi intermetallic compounds is a gradual evolution process with the increase in Si content,following the formation law of Fe→FeSi→Fe_(3)Si+FeSi→FeSi.The metallic impurities of the final product were 1.29 wt.%Mg and 3.85 wt.%Al,respectively.

关键词： Ferroalloy Intermetallic compound Molten salt electrolysis Copper slag Formation process

Pre-operative enhanced magnetic resonance imaging combined with clinical features predict early recurrence of hepatocellular carcinoma after radical resection

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1192-1203页

作者： Jian-Ping Chen Ri-hui yang Tian-hui Zhang Li-An Liao yu-Ting Guan Hai-yang Dai Department of Intervention Meizhou People’s HospitalMeizhou 514031Guangdong ProvinceChina Department of Medical Imaging Meizhou People’s HospitalMeizhou 514031Guangdong ProvinceChina Department of Medical Imaging Huizhou Municipal Central HospitalHuizhou 516001Guangdong ProvinceChina

BACKGROUND Indentifying predictive factors for postoperative recurrence of hepatocellular carcinoma(HCC)has great significance for patient prognosis.AIM To explore the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)enhanced magnetic resonance imaging(MRI)combined with clinical features in predicting early recurrence of HCC after resection.METHODS A total of 161 patients with pathologically confirmed HCC were enrolled.The patients were divided into early recurrence and non-early recurrence group based on the follow-up results.The clinical,laboratory,pathological results and Gd-EOB-DTPA enhanced MRI imaging features were analyzed.RESULTS Of 161 patients,73 had early recurrence and 88 were had non-early recurrence.Univariate analysis showed that patient age,gender,serum alpha-fetoprotein level,the Barcelona Clinic Liver Cancer stage,China liver cancer(CNLC)stage,microvascular invasion(MVI),pathological satellite focus,tumor size,tumor number,tumor boundary,tumor capsule,intratumoral necrosis,portal vein tumor thrombus,large vessel invasion,nonperipheral washout,peritumoral enhancement,hepatobiliary phase(HBP)/tumor signal intensity(SI)/peritumoral SI,HBP peritumoral low signal and peritumoral delay enhancement were significantly associated with early recurrence of HCC after operation.Multivariate logistic regression analysis showed that patient age,MVI,CNLC stage,tumor boundary and large vessel invasion were independent predictive factors.External data validation indicated that the area under the curve of the combined predictors was 0.861,suggesting that multivariate logistic regression was a reasonable predictive model for early recurrence of HCC.CONCLUSION Gd-EOB-DTPA enhanced MRI combined with clinical features would help predicting the early recurrence of HCC after operation.

关键词： Hepatocellular carcinoma Enhanced magnetic resonance imaging Microvascular invasion Hepatobiliary phase Recurrence

Breaking the temperature limit of hydrothermal carbonization of lignocellulosic biomass by decoupling temperature and pressure

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Green Energy & Environment 2023年第4期8卷 1216-1227页

作者： Shijie yu Xiaoxiao yang Qinghai Li yanguo Zhang hui Zhou Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Beijing Key Laboratory of CO_(2) Utilization and Reduction TechnologyDepartment of Energy and Power EngineeringTsinghua UniversityBeijing100084China

Hydrothermal carbonization(HTC) of lignocellulosic biomass is a promising technology for the production of carbon materials with negative carbon emissions. However, the high reaction temperature and energy consumption have limited the development of HTC technology. In conventional batch reactors, the temperature and pressure are typically coupled at saturated states. In this study, a decoupled temperature and pressure hydrothermal(DTPH) reaction system was developed to decrease the temperature of the HTC reaction of lignocellulosic biomass(rice straw and poplar leaves). The properties of hydrochars were analyzed by scanning electron microscopy(SEM), Fourier transform infrared(FTIR) spectroscopy, X-ray photoelectron spectroscopy(XPS), Raman spectroscopy, X-ray diffraction(XRD), thermogravimetric analyzer(TGA), etc. to propose the reaction mechanism. The results showed that the HTC reaction of lignocellulosic biomass could be realized at a low temperature of 200℃ in the DTPH process, breaking the temperature limit(230℃) in the conventional process. The DTPH method could break the barrier of the crystalline structure of cellulose in the lignocellulosic biomass with high cellulose content, realizing the carbonization of cellulose and hemicellulose with the dehydration, unsaturated bond formation, and aromatization. The produced hydrochar had an appearance of carbon microspheres, with high calorific values, abundant oxygen-containing functional groups, a certain degree of graphitization, and good thermal stability. Cellulose acts not only as a barrier to protect itself and hemicellulose from decomposition, but also as a key precursor for the formation of carbon microspheres. This study shows a promising method for synthesizing carbon materials from lignocellulosic biomass with a carbon-negative effect.

关键词： Biomass Lignocellulose Hydrothermal treatment Hydrochar Carbon materials

Synthesis of substitutional hexaboride of lanthanum and cerium La_(1-x)Ce_(x)B_(6) via aluminothermic reduction

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Journal of Rare Earths 2023年第11期41卷 1780-1788,I0005页

作者： yu Wang Xiao-hui yang Jian Cui Guo-Hua Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Green Recovery and Extraction of Rare and Precious Metals University of Science and Technology BeijingBeijing 100083China

Rare-earth hexaborides(REB_(6))are vital raw materials for cathode materials and high temperature structural ceramics that are widely applied as high-frequency electron tubes and ceramics adaptive for extreme environment,respectively.In this work,single phase substitutional solid solution REB_(6)(LaB_(6),La_(0.75)Ce_(0.25)B_(6).La_(0.5)Ce_(0.5)B_(6),La_(0.25)Ce_(0.75)B_(6) and CeB_(6))powders were prepared with the raw materials of La_(2)O_(3),CeO_(2),B_(4)C and Al powders,after calcining at 1773 K for 4 h and the following alkaline leaching.All substitutional solid solution products have homogeneous distributions of La and Ce in particles.Through microscopic morphology analysis,it is discovered that the formation of solid solution is beneficial for reducing the particle size of product,relative to LaB_(6) and CeB_(6).Moreover,Al flux plays an important role in decarbonizing reaction,and C contents of all products are below 0.4 wt%.

关键词： Hexaboride Substitutional solid solution Aluminothermic reduction Rare earths

Texture Induced by Molecular Weight Dispersity: Polymorphism within Poly(L-lactic acid) Spherulites

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Chinese Journal of Polymer Science 2020年第12期38卷 1365-1373页

作者： Da-Peng Hu Min Chen Yu-Hui Yang Han-Ying Li Ministry of Education Key Laboratory of Macromolecular Synthesis and Funtinalizatin Department of Polymer Science and EngineeringZhejing UniversityHangzhou 310027 China

Poly(L-lactic acid)(PLLA)has drawn much attention due to its excellent medical and pharmaceutical applications for decades.As a semi-crystalline polymer,morphology and crystal structure of PLLA greatly determine its properties.Here,w e demonstrate,for PLLA films,a nonconventional texture featuring two types of spherulites emerging in pairs to form a distinct nested structure where a small spherulite(〜10μm)is embedded in a large one(100μm to 300μm).In addition to the size,the molecular weight and polymorph are different in the large and small spherulites.Crystallographic a-form and relatively low molecular weight are identified in the large spherulites,while meta-stable a'-form and relatively high molecular weight in the small ones.These differences suggest that the polydisperse PLLA polymers fractionate during film formation and the high-molecular-weight fraction crystallizes into the small spherulites with meta-stable structure because of its complicated polymer entanglement and high viscosity.In contrast,the rest of polymers crystallize into the large spherulites with the thermodynamically stable polymorph.Furthermore,this texture exhibits accelerated PLLA degradation initiated from the small spherulites,which is distinct from the typical PLLA spherulites.Insights provided by this work may lead to new texture-properties relationship associated with polydispersity of molecular weight.

关键词： PLLA Spherulite Polymorphs Molecular weight

Lower risk of male infanticide in multilevel primate societies

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Zoological Research 2023年第2期44卷 370-373页

作者： Yi-Lin Xiang yang yu hui-Juan Pan Ming Li School of Arts and Design Beijing Forestry UniversityBeijing 100083China School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China CAS Key Lab of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China

DEAR EDITOR,Male infanticide is considered a severe manifestation of sexual conflict in non-human primates during male takeover or male dominance changes. Males engaging in infanticide may obtain fitness benefits, but at the cost of female reproductive outcomes. Consequently, females have developed various anti-infanticide counterstrategies, such as coalitions, dispersal.

关键词： dispersal Lower changes.

Polyhydroxylated eudesmane sesquiterpenoids and sesquiterpenoid glucoside from the flower buds of Tussilago farfara

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Chinese Journal of Natural Medicines 2022年第4期20卷 301-308页

作者： LI yu-Peng yang Kang MENG hui SHEN Tao ZHANG Hua School of Biological Science and Technology University of JinanJinan 250022China Key Laboratory of Chemical Biology(MOE) School of Pharmaceutical SciencesShandong UniversityJinan 250012China

Chemical fractionation of the n-BuOH partition,which was generated from the EtOH extract of the flower buds of Tussilago farfara,afforded a series of polar constituents including four new sesquiterpenoids(1-4),one new sesquiterpenoid glucoside(5)and one known analogue(6)of the eudesmane type,as well as five known quinic acid derivatives(7-11).Structures of the new compounds were unambiguously characterized by detailed spectroscopic analyses,with their absolute configurations being established by A-ray crystallography,electronic circular dichroism(ECD)calculation and induced ECD experiments.The inhibitory effect of all the isolates against LPS-induced NO production in murine RAW264.7 macrophages was evaluated,with isochlorogenic acid A(7)showing significant inhibitory activity.

关键词： Tussilago farfara Eudesmane sesquiterpenoid Anti-inflammation NO production inhibition Quinic acid derivative

Entropy versus enthalpy in hexagonal-close-packed highentropy alloys

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Rare Metals 2022年第8期41卷 2906-2920页

作者： Xin-Wei yang Xiao-hui Shi hui-Jun yang Jun-Wei Qiao Peter KLiaw yu-Cheng Wu College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China School of Materials Science and Engineering University of TennesseeKnoxville37996USA School of Materials Science and Engineering Hefei University of TechnologyHefei230000China

The addition of hexagonal-close-packed(hcp)non-rare-earth elements Zr,Ti and Co,to the 10-component hep rare-earth-based high-entropy alloys(HEAs)with a composition of ScYLaNdGdTbDyHoErLuX(X=Zr,Co and Ti)was investigated.The enthalpy of mixing between elements was found to have a significant effect on the formation of phases.The addition of Co combines with elements that had a strong chemical affinity to form intermetallic compounds by the effect of enthalpy.Ti was added with all elements with poor chemical affinity and exhibited rejection to form a phase alone.These were the two terminal manifestations of the role of enthalpy over entropy.Part of Zr was soluble in the matrix under the action of entropy,while the other part had a greater affinity for Sc than the other elements to form a precipitate under the action of enthalpy.This was the result of the local balance between the effect of enthalpy and entropy.The solid solution of the elements had different degrees of strengthening effect,among which Zr had the most excellent strengthening effect from 185 to 355 MPa,so the solid solution strengthening model and precipitation strengthening model were proposed to predict the strength of the alloy with the addition of Zr effectively.

关键词： High-entropy alloys Hexagonal close-packed(hcp) Phase formation rule Configuration entropy Mechanical properties