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Doping engineering of iron oxide nanoparticles towards high performance and biocompatible T_(1)-weighted MRI contrast agents

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Rare Metals 2024年第1期43卷 298-308页

作者： xue xu Ping-li Dong Yu-Yun Chai Run Yang zhen-Hui Ma Chi-Chong Lu Department of Chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China Department of Physics Beijing Technology and Business UniversityBeijing 100048China

Extremely small-sized iron oxide nanoparticles(IONPs) are of great interest in magnetic resonance imaging(MRI) due to their biosafety as an alternative to clinical gadolinium(Ⅲ) complexes-based contrast *** when the particle size is less than 10 nm,it has strong diffusion ability and deep penetration distance in tumor *** doping can significantly enhance the T_(1)contrast effect of nanoparticles by regulating the surface exposed ***,the nucleation and growth processes of multi-component synthesis systems are complex and difficult to be accurately controlled,leading to great challenges in the synthesis of ultra-small-sized nanoparticles with different components and ***,extremely smallsized superparamagnetic gadolinium-doped iron oxide nanoparticles(GdIONPs,Gd_(x)Fe_(3-x)O_(4) NPs) with adjustable doping amount and controllable size in the range of 3.5-7.5 nm were synthesized by thermal ***,as-synthesized GdIONPs were surface modified with a highly water-soluble and biocompatible carboxyl-polyethylene glycol-phosphoric acid ligand with high binding ***_(0.65)Fe_(2.35)O_(4) NPs exhibited very high r_(1) relaxivity of 10.6 mmol^(-1)·L·s^(-1) in terms of all metal concentrations and 49.0 mmol^(-1)·L·s^(-1) in terms of gadolinium alone,respectively,3 and 14 times higher than clinical T_(1) contrast agents(Gd-DTPA).GdIONPs can continuously obtain high resolution images of blood vessels,and can be used as an efficient and multifunctional contrast agent for MR T_(1)*** stable and efficient doping strategy provides an easy and effective method to individually optimize the magnetic properties of complex oxides and their relaxation effects for a variety of biomedical applications.

关键词： Iron oxide nanoparticles Small size Magnetic resonance imaging Substitutional doping Gd dopant

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Influence of filler characteristics on particle removal in fluid catalytic cracking slurry under an alternating electric field

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Petroleum Science 2024年第3期21卷 2102-2111页

作者： Qiang li Hui-zhen Yang Can Yang Qing-Zhu Qiu Wei-Wei xu Zhao-Zeng liu College of New Energy China University of Petroleum(East China)Qingdao266580ShandongChina

The characteristics of the packing material under an alternating electric field are an important factor in the removal of FCCS *** this study,the electric field distribution of a separation unit consisting of packed spheres under an alternating electric field is simulated,and the movement mechanism of catalyst particles is ***"effective contact point"model is derived to predict the adsorption of filler contact points on catalyst particles under the alternating electric field,and the model is validated by simulations and *** numerical calculation and experimental results indicate that the electrical properties of the filler spheres,the filler angleθ,and the frequency f of the alternating electric field affect the adsorption of catalyst *** the frequency of the electric field increases,the particle removal efficiency of the high-conductivity filler(silicon carbide)increases and then settles,and the separation efficiency of the low-conductivity filler(glass,zirconia)is not sensitive to the change in electric field frequency.

关键词： Fluid catalyticcracking slurry(FCCS) Particle AC electric field Fillers Removal

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Co_(3)S_(4)-pyrolysis lotus fiber flexible textile as a hybrid electrocatalyst for overall water splitting

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Journal of Energy Chemistry 2024年第2期89卷 336-344,I0008页

作者： Qiulan Zhou zhen liu xuxu Wang Yaqian li Xin Qin lijuan Guo liwei Zhou Weijian xu Academician Workstation Changsha Medical UniversityChangsha 410219HunanChina College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082HunanChina College of Environmental Science and Engineering Hunan UniversityChangsha 410082HunanChina School of Basic Medicine Changsha Medical UniversityChangsha 410219HunanChina

Electrocatalytic overall water splitting(OWS),a pivotal approach in addressing the global energy crisis,aims to produce hydrogen and ***,most of the catalysts in powder form are adhesively bounding to the electrodes,resulting in catalyst detachment by bubble generation and other uncertain interference,and eventually reducing the OWS *** surmount this challenge,we synthesized a hybrid material of Co_(3)S_(4)-pyrolysis lotus fiber(labeled as Co_(3)S_(4)-p LF)textile by hydrothermal and hightemperature pyrolysis processes for electrocatalytic *** to the natural LF textile exposing the uniformly distributed functional groups(AOH,ANH_(2),etc.)to anchor Co_(3)S_(4)nanoparticles with hierarchical porous structure and outstanding hydrophily,the hybrid Co_(3)S_(4)-p LF catalyst shows low overpotentials at 10 m A cm^(-2)(η_(10,HER)=100 m Vη_(10,OER)=240 mV)alongside prolonged operational stability during electrocatalytic *** calculations reveal that the electron transfer from p LF to Co_(3)S_(4)in the hybrid Co_(3)S_(4)-p LF is beneficial to the electrocatalytic *** work will shed light on the development of nature-inspired carbon-based materials in hybrid electrocatalysts for OWS.

关键词： Overall water splitting Hybrid electrocatalyst Textile Lotus fiber Co_(3)S_(4)nanoparticles

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Tracheobronchial intubation using flexible bronchoscopy in children with Pierre Robin sequence:Nursing considerations for complications

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World Journal of Clinical Cases 2022年第19期10卷 6464-6471页

作者： Ying-Long Ye Cai-Feng Zhang li-zhen xu Hui-Feng Fan Jun-zheng Peng Gen Lu Xiao-Yin Hu Department of Respiratory Medicine Guangzhou Women and Children’s Medical CentreGuangzhou 510623Guangdong ProvinceChina

BACKGROUND It has been shown that children with Pierre Robin sequence(PRS)have a higher risk of difficult intubation before *** mask ventilation or tracheobronchial intubation is expected to be challenging,flexible bronchoscopy(FB)is advantageous in airway safety when it is used to guide tracheobronchial intubation(TI).AIM To evaluate the complications of TI using FB in children with PRS and explore the effect of nursing services on postoperative *** One hundred and five children with PRS underwent TI using FB before early mandibular distraction *** hundred and eight children with common pneumonia who did not have a difficult airway were set as the control *** data,success rates of TI,time required for TI,number of TI attempts,and the incidence of postoperative complications were ***,the strategies used to attenuate complications were *** The success rate of TI was 100%in children with PRS,while the success rate at the first attempt in the PRS group was significantly lower than that in the control group(88.6%vs 98.2%,P=0.005).The time required for TI in the PRS group was markedly longer than that in the control group(Plications was noticeably higher in the PRS group(50/105,47.6%)than in the control group(36/108,33.3%)(P=0.034).Seven of 105 PRS children experienced laryngeal edema (LE) (6.7%), compared with one (0.9%) in the control group(P = 0.034). Out of the seven patients who had LE, all were reintubated and managed withsteroids: six recovered with inhaled steroids alone before extubated, and one was given systemiccorticosteroids before *** contributes to a high success rate of TI in children with PRS. To prevent LE, operators shouldpay more attention to catheter material, catheter lubrication and intubation time.

关键词： Clinical nursing Pediatrics Surgical nursing Patient safety Operating room

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Prediction of contact resistance of electrical contact wear using different machine learning algorithms

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Friction 2024年第6期12卷 1250-1271页

作者： zhen-bing CAI Chun-lin li Lei YOU xu-dong CHEN li-ping HE Zhong-qing CAO Zhi-nan ZHANG Tribology Research Institute Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

H62 brass material is one of the important materials in the process of electrical energy transmission and signal transmission,and has excellent performance in all *** the wear behavior of electrical contact pairs is particularly complex when they are in service,we evaluated the effects of load,sliding velocity,displacement amplitude,current intensity,and surface roughness on the changes in contact *** learning(ML)algorithms were used to predict the electrical contact performance of different factors after wear to determine the correlation between different factors and contact *** forest(RF),support vector regression(SVR)and BP neural network(BPNN)algorithms were used to establish RF,SVR and BPNN models,respectively,and the experimental data were trained and *** was proved that BP neural network model could better predict the stable mean resistance of H62 brass alloy after *** analysis shows that the load and current have great influence on the predicted electrical contact *** wear behavior of electrical contacts is influenced by factors such as load,sliding speed,displacement amplitude,current intensity,and surface roughness during *** learning algorithms can predict the electrical contact performance after wear caused by these *** results indicate that an increase in load,current,and surface roughness leads to a decrease in stable mean resistance,while an increase in displacement amplitude and frequency results in an increase in stable mean resistance,leading to a decline in electrical contact *** reduce testing time and costs and quickly obtain the electrical contact performance of H62 brass alloy after wear caused by different factors,three algorithms(random forest(RF),support vector regression(SVR),and BP neural network(BPNN))were used to train and test experimental results,resulting in a machine learning model suitable for predicting the stable mean

关键词： electrical contact wear contact resistance machine learning(ML) neural network

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Collaborative Charging Scheduling in Wireless Charging Sensor Networks

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Computers, Materials & Continua 2024年第4期79卷 1613-1630页

作者： Qiuyang Wang zhen xu Lei Yang School of Electrical and Electronic Engineering Wuhan Polytechnic UniversityWuhan430048China

Wireless sensor networks (WSNs) have the trouble of limited battery power, and wireless charging provides apromising solution to this problem, which is not easily affected by the external environment. In this paper, we studythe recharging of sensors in wireless rechargeable sensor networks (WRSNs) by scheduling two mobile chargers(MCs) to collaboratively charge sensors. We first formulate a novel sensor charging scheduling problem with theobjective of maximizing the number of surviving sensors, and further propose a collaborative charging schedulingalgorithm(CCSA) for WRSNs. In the scheme, the sensors are divided into important sensors and ordinary *** can adaptively collaboratively charge the sensors based on the energy limit ofMCs and the energy demandof sensors. Finally, we conducted comparative simulations. The simulation results show that the proposed algorithmcan effectively reduce the death rate of the sensor. The proposed algorithm provides a solution to the uncertaintyof node charging tasks and the collaborative challenges posed by multiple MCs in practical scenarios.

关键词： Wireless rechargeable sensor network mobile charger collaborative charging adaptive charging

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Epidemiology of congenital diaphragmatic hernia among 24 million Chinese births:a hospital-based surveillance study

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World Journal of Pediatrics 2024年第7期20卷 712-722页

作者： Zhi-Yu Chen Jing Tao Wen-li xu Yu-Yang Gao Wen-Yan li zhen liu Jia-Yuan Zhou li Dai National Center for Birth Defects Monitoring West China Second University HospitalSichuan UniversityNo.17 Section 3 RenminnanluChengdu 610041China The Joint Laboratory for Pulmonary Development and Related Diseases West China Institute of Women and Children’s HealthWest China Second University HospitalSichuan UniversityChengduChina Key Laboratory of Birth Defects and Related Diseases of Women and Children Ministry of EducationSichuan UniversityChengduChina NHC Key Laboratory of Chronobology Sichuan UniversityChengduChina Med‑X Center for Informatics Sichuan UniversityChengduChina

Background The prevalence of congenital diaphragmatic hernia(CDH)varies across countries,with limited information available on its epidemiology in *** study aimed to investigate the prevalence,time trends,and perinatal outcomes of CDH in China,as well as its associated malformations and potential associations with maternal and infant *** This study included all birth and CDH cases from the Chinese Birth Defects Monitoring Network between 2007 and 2019,with CDH cases classified as either isolated or *** employed the joinpoint regression model to calculate the trends of prevalence and the annual percent change,with Poisson regression used for adjusted prevalence rate ratios.A P value≤0.05 was considered statistically *** A total of 4397 CDH cases were identified among 24,158,029 births in the study period,yielding prevalence rates of 1.82,1.13 and 0.69 per 10,000 for overall,isolated,and associated CDH,*** prevalence of each type of CDH increased over *** prevalence of overall CDH varied significantly by infant sex(male ***,1.91/10,000 vs.1.63/10,000),maternal residence(urban ***,2.13/10,000 vs.1.45/10,000),maternal age(lies were the most common malformations associated with *** with associated CDH had a higher risk of premature birth and perinatal death than those with isolated *** The increasing prevalence and high perinatal mortality rate of CDH highlight the need for further etiological,epidemiological,and clinical studies among the Chinese population.

关键词： China Congenital diaphragmatic hernia Epidemiology Prevalence

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Highly efficient photo-thermal synergistic catalysis of CO_(2)methanation over La_(1-x)Ce_(x)NiO_(3)perovskite-catalyst

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Nano Research 2024年第9期17卷 7945-7956页

作者： Ting li zhen-Yu Zhang De-Cun Luo Bo-Yu xu Rong-Jiang Zhang Ji-Long Yao Dan li Tao Xie Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases ***,designing advanced photo-thermal catalysts remains a research challenge for CO_(2)methanation *** this work,a series of ABO3(A=lanthanide,B=transition metal)perovskite catalysts with Ce-substituted LaNiO3(La_(1-x)Ce_(x)NiO_(3),x=0,0.2,0.5,0.8,1)were synthesized for CO_(2)*** La_(0.2)Ce_(0.8)NiO_(3) exhibited the highest CH_(4) formation rate of 258.9 mmol·g^(-1)·hcat-1,CO_(2)conversion of 55.4%and 97.2%CH_(4) selectivity at 300℃with the light intensity of 2.9 W·cm^(-2).Then the catalysts were thoroughly analyzed by physicochemical structure and optical properties *** partial substitution of the A-site provided more active sites for the adsorption and activation of CO_(2)/H_(2).The sources of the active sites were considered to be the oxygen vacancies(O_(v))created by lattice distortions due to different species of ions(La^(3+),Ce^(4+),Ce^(3+))and exsolved Ni0 by H_(2)*** catalysts have excellent light absorption absorbance and low electron-hole(e^(-)/h^(+))recombination rate,which greatly contribute to the excellent performance in photo-thermal synergistic catalysis(PTC)CO_(2)*** results of in situ irradiated electron paramagnetic resonance spectrometer(ISI-EPR)and ISI-X-ray photoelectron spectroscopy(XPS)indicated that the aggregation of unpaired electrons near the defects and Ni metal(from La and Ce ions to Ov and Ni0)accelerated adsorption and activation of CO_(2)/H_(2).At last,the catalyst properties and structure were correlated with the proposed reaction mechanism from the in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)*** in situ precipitation of the B-site enhanced the dispersion of Ni,while its enriched photoelectrons upon illumination further promote hydrogen *** H^(*)spillover accelerated t

关键词： photo-thermal catalysis CO_(2)methanation perovskite A-site substitution in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)

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Recent advances in Pt catalysts and membrane electrode assemblies fabrication for proton exchange membrane fuel cells

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Rare Metals 2024年第9期43卷 4198-4221页

作者： Miao Ma li-Xiao Shen Jing liu Bin xu Yun-Long Zhang Lei Zhao zhen-Bo Wang School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China College of Environmental and Chemical Engineering Yanshan UniversityQinhuangdao 066004China Unipower Hydrogen Technology(Jiangsu)Corporation Changzhou 213176China

Proton exchange membrane fuel cells(PEMFCs)have been identified as a highly promising means of achieving sustainable energy conversion.A crucial factor in enhancing the performance of PEMFCs for further potential energy applications is the advancement in the field of catalyst engineering that has led to remarkable performance enhancement in facilitating the oxygen reduction reaction(ORR).Subsequently,it is important to acknowledge that the techniques used in preparation of membrane electrode assemblies(MEAs),the vital constituents of PEMFCs,also possess direct and critical influence on exhibiting the full catalytic activity of meticulously crafted ***,a succinct summary of the most recent advancements in Pt catalysts for ORR was offered and their underly catalytic mechanism were ***,both laboratory-scale and industrial-scale MEA fabrication techniques of Pt catalysts were ***,a detailed analysis of the connections between materials,process,and performance in MEA fabrication was presented in order to facilitate the development of optimal catalyst layers.

关键词： Pt catalysts Oxygen reduction reaction Membrane electrode assemblies MEA fabrication techniques

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Fabrication of MXene-Bi_(2)WO_(6)heterojunction by Bi_(2)Ti_(2)O_(7)hinge for extraordinary LED-light-driven photocatalytic performance

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Nano Research 2024年第6期17卷 4729-4736页

作者： Zhiwen li liangliang xu Zaheer Ud Din Babar Ali Raza Yifei Zhang Xinrui Gu Yu-Xin Miao zhen Zhao Gao li Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Scuola Superiore Meridionale(SSM) University of Naples Federico IILargo S.Marcellino1080138Italy Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea University of Chinese Academy of Sciences Beijing 100049China

Heterojunction composites with intimate interfaces can shorten the diffusion distance,which leads to a shorter path for photogenerated carriers,thereby increasing photocatalytic ***,we report the fabrication of Ti_(3)C_(2)-Bi_(2)WO_(6)(TC-BW)heterojunctions hinged by Bi_(2)Ti_(2)O_(7)joints via an in situ hydrothermal reaction of Ti_(3)C_(2)in the presence of Na_(2)WO_(4)and Bi(NO_(3))_(3).The TC-BW was characterized using X-ray diffraction(XRD),scanning transmission electron microscopy(STEM),and Raman ***-BW showed superior photocatalytic activity(productivity over 15TC-WB reaches up to 5.0 mmolreacted BA·gcat.^(−1)·h^(−1))in the oxidation of benzyl alcohol using light-emitting diode(LED)light,arising from the surface defects and intimate heterojunction interface between the Ti_(3)C_(2)MXene and Bi_(2)WO_(6)***-BW heterojunctions provide an enhanced separation efficiency of photogenerated charges,which in turn yields superior photocatalytic ***,it is well substantiated by density functional theory(DFT)*** summary,this study elucidates the preparation of heterojunction composites with intimate interfaces for highly efficient photooxidation.

关键词： MXene-Bi_(2)WO_(6) heterojunction LED-light-driven photocatalysis Bi_(2)Ti_(2)O_(7) photooxidation

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