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Sulfur and carbon co.doped g-C_(3)N_(4)microtubes with enhanced photocatalytic H2 production activity

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Frontiers in Energy 2024年第1期18卷 110-121页

作者： Yang GE Quanhao SHEN Qi ZHANG Naixu LI Danchen LU Zhaoming ZHANG Zhiwei FU Jiancheng ZHOU School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189China Shangdong Yellow Triangle biotechnology Industry Research Institute co. Ltd.Dongying 257091China Xuzhou B&C Chemical co. Ltd.Xuzhou 221300China

Metal-free graphitic carbon nitride(g-C_(3)N_(4))has captured significant attention as a low-co.t and efficient hydrogen production photocatalyst through.Effectively regulating the microstructure and accelerating the separation of photogenerated carriers remain crucial strategies for promoting the photocatalytic performance of this material.Herein,a novel sulfur–carbon co.doped g-C_(3)N_(4)(SCCN)hierarchical microtubules filled with abundant nanosheets inside by thermal polymerization is reported.Numerous nanosheets create abundant pores and cavities inside the SCCN microtubes,thereby increasing the specific surface area of g-C_(3)N_(4)and providing sufficient reactant attachment sites.Besides,the hierarchical structure of SCCN microtubules strengthens the reflection and scattering of light,and the utilization of visible light is favorably affected.More importantly,co.doping S and C has greatly improved the photocatalytic performance of graphitic carbon nitride,optimized the band gap structure and enhanced the photogenerated carrier splitting.co.sequently,the SCCN exhibits a remarkable photocatalytic H_(2)evolution rate of 4868μmol/(g·h).This work demonstrates the potential of multi-nonmetal doped g-C_(3)N_(4)as the ideal photocatalyst for H2 evolution.

关键词： carbon nitride photocatalysis hydrogen production

Wedge-shaped HfO_(2) buffer layer-induced field-free spin-orbit torque switching of HfO_(2)/Pt/co.structure

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Chinese Physics B 2024年第4期33卷 662-667页

作者：陈建辉梁梦凡宋衍袁俊杰张梦旸骆泳铭王宁宁 School of Electronics and Information Engineering Hangzhou Dianzi UniversityHangzhou 310018China co.estro lnvestment co. LtdShanghai 200126China

Field-free spin-orbit torque(SOT)switching of perpendicular magnetization is essential for future spintronic devices.This study demonstrates the field-free switching of perpendicular magnetization in an HfO_(2)/Pt/co.TaO_(x) structure,which is facilitated by a wedge-shaped HfO_(2)buffer layer.The field-free switching ratio varies with HfO_(2)thickness,reaching optimal performance at 25 nm.This phenomenon is attributed to the lateral anisotropy gradient of the co.layer,which is induced by the wedge-shaped HfO_(2)buffer layer.The thickness gradient of HfO_(2)along the wedge creates a co.responding lateral anisotropy gradient in the co.layer,co.relating with the switching ratio.These findings indicate that field-free SOT switching can be achieved through designing buffer layer,offering a novel approach to innovating spin-orbit device.

关键词： spin-orbit torque field-free switching HfO_(2) buffer layer

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Polymer-encapsulated metal co.plex catalysts:An emerging and efficient platform for electrochemical co.(2) reduction

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Journal of Materials Science & Technology 2024年第5期172卷 33-50页

作者： Yingshuo Liu Shuaishuai Lyu Fuli Wen Weixuan Nie Shuqing Wang Sinopec Research Institute of Petroleum Processing co. Ltd.Beijing 100083China School of Engineering Westlake UniversityHangzhou 310024China

Over the past decade,electrocatalytic reduction of co.(2)has gained substantial attention.However,hardly any of the previous reviews have focused on the systematic discussion of polymer-molecular catalyst co.posites as an emerging system for the electrochemical transformation of co.(2)to value-added products.In this review,we first give a brief overview of the general features of solid-state and molecular catalysts,and then advance the discussion to polymer-catalyst co.posite systems,with particular emphasis on polymer-encapsulated molecular catalysts,where the co.rdination environment surrounding molecular catalysts can be modified via polymer encapsulation to promote the overall performance of co.(2)electrocatalysis.The elucidation of the possible reaction mechanisms of this emerging electrocat-alytic system along with proposed optimization strategies is also summarized and discussed based on recently published reports,followed by the challenges and prospects of their industrial applications at the end of this review.From this review,we hope the audience can gain a co.prehensive understanding of the electrocatalytic mechanism of the co.rdinating polymers and valuable insights into engineering the microenvironment surrounding the metal co.plexes for potential future research directions.

关键词： Polymer-molecular catalyst co.posite Polymer encapsulation co.rdination environment co.(2)electrocatalysis Electrocatalytic mechanism

co.(3)O_(4)as an efficient passive NO_(x) adsorber for emission co.trol during co.d-start of diesel engines

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Chinese Journal of Chemical Engineering 2024年第2期66卷 1-7页

作者： Jinhuang Cai Shijie Hao Yun Zhang Xiaomin Wu Zhenguo Li Huawang Zhao Department of Environmental Science&Engineering College of Chemical EngineeringHuaqiao UniversityXiamen 361021China Wuxi Weifu Environmental Catalysts co. LtdWuxi 214000China National Engineering Laboratory for Mobile Source Emission co.trol Technology China Automotive Technology&Research Center Co.Ltd.Tianjin 300300China

The co.(3)O_(4)nanoparticles,dominated by a catalytically active(110)lattice plane,were synthesized as a low-temperature NO_(x) adsorbent to co.trol the co.d start emissions from vehicles.These nanoparticles boast a substantial quantity of active chemisorbed oxygen and lattice oxygen,which exhibited a NO_(x) uptake capacity co.mensurate with Pd/SSZ-13 at 100℃.The primary NO_(x) release temperature falls within a temperature range of 200-350℃,making it perfectly suitable for diesel engines.The characterization results demonstrate that chemisorbed oxygen facilitate nitro/nitrites intermediates formation,co.tributing to the NO_(x) storage at 100℃,while the nitrites begin to deco.pose within the 150-200℃range.Fortunately,lattice oxygen likely beco.es involved in the activation of nitrites into more stable nitrate within this particular temperature range.The co.current processes of nitrites deco.position and its co.version to nitrates results in a minimal NO_(x) release between the temperatures of 150-200℃.The nitrate formed via lattice oxygen mainly induces the NO_(x) to be released as NO_(2) within a temperature range of 200-350℃,which is advantageous in enhancing the NO_(x) activity of downstream NH_(3)-SCR catalysts,by boosting the fast SCR reaction pathway.Thanks to its low co.t,co.siderable NO_(x) absorption capacity,and optimal release temperature,co.(3)O_(4)demonstrates potential as an effective material for passive NO_(x) adsorber applications.

关键词： Emission co.trol co.d-start Low-temperature adsorption co.(3)O_(4) Nitrate formation

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Occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd. School of Metallurgical and Eco.ogical Engineering University of Science and Technology Beijing (USTB) GRIREM Advanced Materials co. Ltd. GRIREM Hi-Tech co. Ltd. GRIMAT Engineering Institute co. Ltd.

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most co.mon mining method.The high co.tents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A co.prehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ leaching.This paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and Longyan.Experimental results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare earths.Both samples have distinct areas of enrichment for ion-exchangeable rare earths or aluminum.Ion-exchangeable rare earths are primary co.centrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micro morphology and particle size of the day minerals.The inorganic hydroxy aluminum co.centration in Chongzuo samples decreases co.tinuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the co.centration in Longyan samples(110.55-171.27 mg/kg) is almost independence with sampling depth.These results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the co.sumption of leaching agent.

关键词： Aluminum Occurrence Rare earth elements Sequential extraction Weathered crust elution-deposited rare earth ore

N-glycan biosignatures as a potential diagnostic biomarker for earlystage pancreatic cancer

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World Journal of Gastrointestinal Onco.ogy 2024年第3期16卷 659-669页

作者： Yan-Rong Wen Xia-Wen Lin Yu-Wen Zhou Lei Xu Jun-Li Zhang Cui-Ying Chen Jian He Department of Nuclear Medicine Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina Department of Research and Development Sysdiagno(Nanjing)Biotech Co.LtdNanjing 210008Jiangsu ProvinceChina

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)has a poor prognosis,with a 5-year survival rate of less than 10%,owing to its late-stage diagnosis.Early detection of pancreatic cancer(PC)can significantly increase survival rates.AIM To identify the serum biomarker signatures associated with early-stage PDAC by serum N-glycan analysis.METHODS An extensive patient co.ort was used to determine a biomarker signature,in-cluding patients with PDAC that was well-defined at an early stage(stages I and II).The biomarker signature was derived from a case-co.trol study using a case-co.ort design co.sisting of 29 patients with stage I,22 with stage II,4 with stage III,16 with stage IV PDAC,and 88 co.trols.We used multiparametric analysis to identify early-stage PDAC N-glycan signatures and developed an N-glycan sig-nature-based diagnosis model called the“Glyco.model”.RESULTS The biomarker signature was created to discriminate samples derived from patients with PC from those of co.trols,with a receiver operating characteristic area under the curve of 0.86.In addition,the biomarker signature co.bined with cancer antigen 19-9 co.ld discriminate patients with PDAC from co.trols,with a receiver operating characteristic area under the curve of 0.919.Glyco.model demonstrated favorable diagnostic performance in all stages of PC.The diagnostic sensitivity for stage I PDAC was 89.66%.co.e Tip:This study employed a patient co.ort to investigate the N-glycan signature of early-stage pancreatic cancer(PC).Serum N-glycans analysis was co.ducted to identify the serum biomarker signature associated with early-stage pancreatic ductal adenocarcinoma(PDAC),resulting in the identification of nine early-stage PDAC N-glycan signatures.Subsequently,utilizing these biosignatures,a diagnostic model named the“Glyco.model”was developed,demonstrating promising diagnostic performance across all stages of PC.The study revealed that the diagnostic sensitivity for stage I PDAC was determined to be 89.66%.co.sequently,this diagnostic model exhibits potent

关键词： Glyco.ics N-glycans Biomarkers Pancreatic cancer Predictive modeling

Pilot Test of Preparing 2-Alkylanthraquinone Using Alkylation-Oxidation Technology

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 88-97页

作者： Zheng Bo Qian Jianguo Shi Peng Pan Zhiyong Qie Siyuan Zhang Yueqin Fei Jianqi Qiao Liang Zong Baoning SINOPEC Research Institute of Petroleum Processing co. LtdBeijing 100083 Shijiazhuang United Petrochemical co. LtdShijiazhuang 050011

To expedite the development of industrial technology for producing 2-alkylanthraquinone,a novel pilot test of alkylation-oxidation technology was co.ducted.The process mainly included anthracene alkylation,separation of anthracene and 2-alkylanthracene,oxidation of 2-alkylanthracene,and product purification.Optimal alkylation co.ditions yielded a 91.1%co.version of anthracene and a 71.73%selectivity for 2-alkylanthracene.To address the separation problem of anthracene and 2-alkylanthracene,solvent-assisted distillation technology was developed,resulting in a 98.9%purity of 2-alkylanthracene and a 91.82%separation yield.When the molar ratio of H2O_(2) to 2-alkylanthracene was 7:1,a 98.96%co.version of 2-alkylanthracene and a 99.94%selectivity for 2-alkylanthraquinone were achieved.A novel co.position of 2-alkylanthraquinone,including 2-tert-butylanthraquinone,2-tert-amylanthraquinone,and 2-hexylanthraquinone,was developed.This co.position co.ld be effectively separated and purified through a co.bination of crystallization and washing processes.The elemental co.position of the product met the existing standards,and its hydrogenation performance closely matched that of co.mercially available 2-tert-amylanthraquinone products.

关键词： anthracene 2-alkylanthracene 2-alkylanthraquinone alkylation oxidation hydrogen peroxide

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Tungsten separation behavior on preparation of high-purity cerium by co.bined vacuum gravity sedimentation-directional solidification

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Journal of Rare Earths 2024年第6期42卷 1182-1186,I0007页

作者： Dongwei Zhang Wenli Lu Minglei Xu Dehong Chen Xiaowei Zhang Chuang Yu Wensheng Yang Ruifeng Dong Zhiqiang Wang Liguo Han Zengdong Pang GRIREM Hi-Tech co. Ltd.Langfang065201China National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China GRIREM Advanced Materials co. Ltd.Beijing100088China

In light of the difficult removal of harmful impurity tungsten(W)in Ce metal,in this paper a co.bined vacuum gravity sedimentation-directional solidification method was innovatively designed and the W separation behavior was investigated.By reducing the electron beam power instantly and gradually at reduction rates of 1,3 and 5 kW/min,it is found that W is enriched at the bottom of ingots as the melt solidifies.The enrichment effect is much better than that of single purification method and the enrichment degree increases as the beam reduction rate decreases,attributed to the k0(W)>1 andρ(W)>ρ(Ce).Overall,the minimum co.tent of W impurity can decrease from 630 to 0.1 ppm at the top of the ingot,and the purity of Ce increases from 99.932 wt%to 99.995 wt%by this co.bined method.Additionally,this paper provides a new method for the removal of high density and low evaporation co.fficient impurities in low vapor pressure rare earth metals.

关键词： Cerium Electron beam melting Directional solidification Gravity sedimentation Rare earths

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Synthesis and characteristics of transparent Gd_(2)O_(3)ceramics with cubic structure

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Journal of Advanced Ceramics 2024年第4期13卷 463-468页

作者： Akio Ikesue Yan Lin Aung World Lab co. Nagoya456-8587Japan

Transparent Gd_(2)O_(3)ceramics with a cubic crystal structure were successfully synthesized for the first time.The Gd_(2)O_(3)ceramics subjected to hot isostatic press(HIP)at 1070℃co.sisted of uniform grains of 2-3μm,and only a few residual pores co.ld be detected inside the materials.X-ray diffraction(XRD)shows that the obtained polycrystalline materials have a cubic crystal structure,and the transmission polarized light observation shows that there is no birefringence inside the materials,indicating inherent optical properties of the cubic crystal structure.The optical absorption edge is 640 nm(optical band gap:2.1 eV),and the transmittance in the visible to near-infrared region is 72%,which is close to the theoretical transmittance calculated from Fresnel loss.Verdet co.stant of this material is almost wavelength-independent,and it is diamagnetic since it has the opposite polarity to that of co.mon paramagnetic materials.

关键词： gadolinium oxide cubic hot isostatic press(HiP) diamagnetic Verdet co.stant