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提高质量:现代远程教育发展的战略性课题

河北学刊 2008年第5期28卷 193-197页

作者：高勇于来虎河北广播电视大学河北石家庄050071

在终身教育浪潮的冲击与高等教育大众化需求的促使下,现代远程教育呈现出强有力的发展势头。目前,教育质量成为远程教育中备受关注的热点和难点问题之一。本文从远程教育的规律和特点出发,分析了当前远程教育所存在的问题,指出远程教育... 详细信息

在终身教育浪潮的冲击与高等教育大众化需求的促使下,现代远程教育呈现出强有力的发展势头。目前,教育质量成为远程教育中备受关注的热点和难点问题之一。本文从远程教育的规律和特点出发,分析了当前远程教育所存在的问题,指出远程教育的质量观、质量标准和质量保证的要素以及提高远程教育质量保证的思路与对策,并试图探索远程教育质量保证的实现途径。

关键词：远程教育远程学习者教育质量观质量保证模式创新

Co/Co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang Chen Yongyue Zhuang Yanxin Qiao yu Zhang Aihua yuan hu Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NCS)decorated with dual-phase Co/Co_(7)Fe_(3)heterojunctions(CoFe@NCS).The phase composition of materials has been adjusted by controlling the alloying *** optimal CoFe_(0.08)@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co_(7)Fe_(3)alloy and metallic Co *** the CoFe_(0.08)@NCS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/C+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

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用加重方法完全平衡平面机构惯性力的条件

河北工业科技 2000年第4期17卷 35-37页

作者：于来虎河北广播电视大学理工部河北石家庄050071

在平面杆机构的设计中 ,惯性力的平衡是经常遇到的问题。

关键词：平面杆机构惯性力完全平衡条件加重方法

Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins

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Neural Regeneration Research 2025年第1期20卷 242-252页

作者： Daiyu hu yuanqing Cao Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan Qiong lai Zhengliang Gao Fundamental Research Center Shanghai Yangzhi Rehabilitation Hospital(Shanghai Sunshine Rehabilitation Center)School of MedicineTongji UniversityShanghaiChina Institute of Geriatrics(Shanghai University) Affiliated Nantong Hospital of Shanghai University(The Sixth People’s Hospital of Nantong)Shanghai University School of MedicineNantongJiangsu ProvinceChina Shanghai Engineering Research Center of Organ Repair Shanghai University School of MedicineShanghaiChina Key Laboratory of Arrhythmias Ministry of EducationShanghai East HospitalSchool of MedicineTongji UniversityShanghaiChina

human brain development is a complex process,and animal models often have significant *** address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and *** enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid *** involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid *** cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology *** a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental *** organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature *** exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic *** convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies.

关键词： cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells neurogenesis neurotoxicology organoids stem cells

Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 204-251页

作者： Jiawen hu Xinwei Li Qianqian Liang Li Xu Changsheng Ding yu Liu Yanfeng Gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China

Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural ***,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in ***,it is of significance to boost the sodium storage performance of NVP cathode *** to now,many methods have been developed to optimize the electrochemical performance of NVP cathode *** this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology *** foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so ***,the challenges and prospects of high-performance NVP cathode material are also put *** is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.

关键词： Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies

Laparoscopic liver resection utilizing the ventral avascular area of the inferior vena cava:A retrospective cohort study

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World Journal of Gastroenterology 2025年第1期31卷 42-57页

作者： Kun huang Zhu Chen Heng Xiao Hai-Yang hu Xing-yu Chen Cheng-You Du Xiang Lan Department of Hepatobiliary Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400000China Department of General Surgery Mianyang Hospital of Traditional Chinese MedicineMianyang 621000Sichuan ProvinceChina

BACKGROUND Laparoscopic liver resection(LLR)can be challenging due to the difficulty of establishing a retrohepatic tunnel under *** the third hepatic hilum before parenchymal transection often leads to significant liver mobilization,tumor compression,and bleeding from the short hepatic veins(SHVs).This study introduces a novel technique utilizing the ventral avascular area of the inferior vena cava(IVC),allowing SHVs to be addressed after parenchymal transection,thereby reducing surgical complexity and improving outcomes in in situ *** To introduce and evaluate a novel LLR technique using the ventral avascular area of the IVC and compare its short-term outcomes with conventional *** The clinical cohort data of patients with pathologically confirmed hepatocellular carcinoma or intrahepatic cholangiocarcinoma who underwent conventional LLR and novel LLR between July 2021 and July 2023 at the First Affiliated Hospital of Chongqing Medical University were retrospectively *** novel LLR,we initially separated the caudate lobe from the IVC using dissecting forceps along the ventral avascular area of the ***,we transected the parenchyma of the left and right caudate lobes from the caudal side to the cephalic side using the avascular area as a ***,we addressed the SHVs and finally dissected the root of the right hepatic vein or left hepatic *** short-term postoperative outcomes and oncological results of the two approaches were evaluated and *** A total of 256 patients were included,with 150(58.59%)undergoing conventional LLR and 106(41.41%)undergoing novel *** novel technique resulted in significantly larger tumor resections(6.47±2.96 cm vs 4.01±2.33 cm,P<0.001),shorter operative times(199.57±60.37 minutes vs 262.33±83.90 minutes,P<0.001),less intraoperative blood loss(206.92±37.09 mL vs 363.34±131.27 mL,P<0.001),and greater resection volume(345.11±31.40 mL vs 264.38±31.98 mL,P<0.001)comp

关键词： Laparoscopic liver resection Inferior vena cava Retrohepatic tunnel Short hepatic veins Complex liver tumors Intraoperative bleeding control

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： yumeng Wang Qinyi Guo Bin hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

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人才培养模式改革试点的成就及其未来走向

河北师范大学学报（教育科学版） 2008年第5期10卷 115-118页

作者：张俊芳于来虎白玉文河北广播电税大学河北石家庄050071

1999年教育部批准的"试点"项目是"国家现代远程教育工程"的重要组成部分,由教育部直接领导、电大系统组织和具体实施。通过八年试点,河北广播电视大学的信息化基础设施建设取得突破性进展,形成了天、地、人网结合,三级教学平台互动的网... 详细信息

1999年教育部批准的"试点"项目是"国家现代远程教育工程"的重要组成部分,由教育部直接领导、电大系统组织和具体实施。通过八年试点,河北广播电视大学的信息化基础设施建设取得突破性进展,形成了天、地、人网结合,三级教学平台互动的网络教学环境;积累了一大批适应自主学习的多种媒体教学资源,探索出了符合河北实际的现代远程开放教育人才培养模式基本框架以及教学模式、管理模式和质量保证体系。在学习型社会建设的进程中,开放教育将向理念更加成熟、资源更加丰富、运行更加高效、服务更加优质、质量更有保障的方向发展。

关键词：开放教育试点现代远程教育人才培养模式学习型社会

Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance Li–CO_(2)Batteries in a Wide‑Temperature Range

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Nano-Micro Letters 2025年第1期17卷 160-175页

作者： Tingsong hu Wenyi Lian Kang hu Qiuju Li Xueliang Cui Tengyu Yao laifa Shen Jiangsu Key Laboratory of Materials and Technologies for Energy Storage College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction ***,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as *** unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon *** illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 *** at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT *** work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.

关键词： Li-CO_(2)batteries Photo-energized Wide operation-temperature Kinetics MoS_(2)