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Review of China's policy and management system for the paid use of sea area Feng 被引量:1
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作者 feng li Zenglei Xi Xiangbo liang 《Chinese Journal of Population,Resources and Environment》 2019年第1期58-66,共9页
As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the e... As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the early 1990s, China has begun to implement the paid use and formed an institutional system comprised of three levels after developing it for more than two decades. From 2002 to 2015, the Chinese Government transferred the use right of sea area of 33,910 km2 by paid use and levied a total of 75.89 billion CNY (11.328 billion US dollars) of sea area use payment. Apart from this, the Government has gained rich experience in operating and managing the compensable use of sea area. After retrospectively analyzing the development history of paid use of China’s sea area, the research presents an institutional structure and the implementation of the management system for the paid use of sea area and the main problems therein. On this basis, management policies and feasible policy suggestions are proposed. Research results from this study can provide available references for other developing countries and emerging economies to apply and improve native management system for the paid use of sea area. 展开更多
关键词 PAID USE SEA area POLICY management system China
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Research Status of High-Entropy Alloys Based on Artificial Intelligence Technology
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作者 YU Zhiqi ZHAO Yanchun +5 位作者 XUE Baorui DANG Wenxia MA Huwen SU Yu LAN Yunbo feng li 《有色金属(中英文)》 北大核心 2025年第5期735-747,共13页
High-Entropy Alloys(HEAs)exhibit significant potential across multiple domains due to their unique properties.However,conventional research methodologies face limitations in composition design,property prediction,and ... High-Entropy Alloys(HEAs)exhibit significant potential across multiple domains due to their unique properties.However,conventional research methodologies face limitations in composition design,property prediction,and process optimization,characterized by low efficiency and high costs.The integration of Artificial Intelligence(AI)technologies has provided innovative solutions for HEAs research.This review presented a detailed overview of recent advancements in AI applications for structural modeling and mechanical property prediction of HEAs.Furthermore,it discussed the advantages of big data analytics in facilitating alloy composition design and screening,quality control,and defect prediction,as well as the construction and sharing of specialized material databases.The paper also addressed the existing challenges in current AI-driven HEAs research,including issues related to data quality,model interpretability,and cross-domain knowledge integration.Additionally,it proposed prospects for the synergistic development of AI-enhanced computational materials science and experimental validation systems. 展开更多
关键词 high-entropy alloys artificial intelligence structural modeling mechanical property big data
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Diagnostic Value of TB-IGRA, PPD, TB-DNA-PCR and TB-Ab in Silicosis Complicated with Tuberculosis 被引量:2
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作者 Weijia lin Zhi liu +3 位作者 Yaping Zhang feng li Xiulong Zhang Zhihua Zhang 《Journal of Tuberculosis Research》 2021年第2期110-116,共7页
</span><b><span style="font-family:Verdana;">Purpose</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verd... </span><b><span style="font-family:Verdana;">Purpose</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></b></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">The purpose of this article is </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">to investigate the clinical value of TB-IGRA</span><span style="font-family:Verdana;"> (Tuberculosis-Interferon </span><span style="font-family:Verdana;">Gamma Release Assay), PPD (Intradermal </span><span style="font-family:Verdana;">Terbuculin Test), TB-DNA-PCR (Tuberculosis-Deoxyribonucleic-Polymerase</span><span style="font-family:Verdana;"> Chain Reaction) and TB-Ab (Tuberculosis-Antibody) in diagnosing silicosis complicated with pulmonary tuberculosis. <b></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Methods</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></b></span></span></span><span><span><b><span style="font-family:""> </span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">53 cases of suspected silicosis complicated with pulmonary tuberculosis were selected in the time span ranging from February 2017 to May 2019. TB-IGRA test, PPD test, TB-DNA-PCR and TB-Ab detection were performed. The sensitivity, specificity, positive predictive value and negative predictive value were calculated. </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Results</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></b></span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Silicosis and pulmonary tuberculosis were diagnosed in 11 cases, with an incidence of 20.75%. The positive rates of TB-IGRA, PPD, TB-DNA-PCR and TB-Ab were 66.04%, 30.19%, 5.67% and 26.42%, respectively. The sensitivity was 90.91%, 81.82%, 27.27% and 54.55% respectively. The specificity was 42.86%, 80.95%, 100% and 80.95% respectively. The positive predictive values were 28.57%, 50%, 100% and 42.86% respectively. The negative predictive values were 94.44%, 91.89%, 84% and 87.18%. The positive rate, sensitivity and negative predictive value of TB-IGRA were the highest, while the specificity of TB-DNA-PCR was the highest yet with low positive rate, sensitivity and positive predictive value. </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Conclusion</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"></b></span></span></span><span><span><b><span style="font-family:""> </span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">The positive rate and sensitivity of TB-IGRA were high, yet with poor specificity, so it was impossible to judge whether the cases belonged to active pulmonary tuberculosis. The combination of PPD and TB-DNA-PCR could improve the sensitivity, specificity and positive predictive value, and the diagnostic accuracy of active pulmonary tuberculosis, which showed satisfactory clinical value. 展开更多
关键词 TB-IGRA PPD TB-DNA-PCR TB-AB Diagnosis
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Structure-activity relationship on tensile properties under DRX and slip system activity of U-CVCDEed AZ31 magnesium alloy
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作者 Qiang liu feng li +2 位作者 Fu Wei Kang Hai Bo Wang Shun Luo 《Journal of Magnesium and Alloys》 2025年第8期3906-3917,共12页
Given the limitations of traditional hot extrusion methods in improving the microstructure and mechanical properties of magnesium(Mg)alloys,this paper attempts to treat AZ31 Mg alloy billet by pre-upsetting continuous... Given the limitations of traditional hot extrusion methods in improving the microstructure and mechanical properties of magnesium(Mg)alloys,this paper attempts to treat AZ31 Mg alloy billet by pre-upsetting continuous variable cross-section direct extrusion(U-CVCDE).The effects of dynamic recrystallization behavior and slip system activity on texture evolution and mechanical properties of CVCDE Mg alloys with different pre-upsetting amounts were systematically analyzed.The results indicate that the introduction of the pre-upsetting process promotes dynamic recrystallization during the CVCDE process.The recrystallization proportion shows a trend of first rising and then decreasing with the increase of the pre-upsetting amount.Among them,the proportion of recrystallization grains in the U2-CVCDE-formed structural parts is as high as 88.3%.The average grain sizes of U1-CVCDE,U2-CVCDE,and U3-CVCDE were 6.01μm,4.90μm,and10.45μm,respectively.In addition,following U-CVCDE,the pyramidal slip of each forming component consistently maintains a high level of activation and opening and dominates,making more grains deflect in the axial extrusion direction of C to varying degrees,which is conducive to the uniform distribution of stress in more grains during plastic deformation.The synergistic effect of dynamic recrystallization behavior and the high activity of the pyramidal slip system significantly weakened the(0001)basal texture strength,and the maximum basal texture strength showed a gradually decreasing trend,among which the base surface texture strength of U3-CVCDE formed parts was only 9.9.The U-CVCDE process is employed to achieve deep modification of Mg alloy,and excellent comprehensive mechanical properties are obtained;among them,the yield and tensile strength of U2-CVCDE are as high as 243.4 MPa and 317.5 MPa,respectively,and the elongation after breaking is up to 21.3%.This study introduces a practical new idea for investigating the extrusion forming technology of high-performance Mg alloys. 展开更多
关键词 Pre-upsetting treatment CVCDE RECRYSTALLIZATION Slip system TEXTURE Mechanical property
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舒筋健腰丸联合OLIF一期经皮椎弓根螺钉治疗退行性腰椎滑脱疗效观察 被引量:5
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作者 彭博文 冯立 +2 位作者 张涛 谢添 董晓俊 《现代中西医结合杂志》 CAS 2021年第10期1061-1065,1072,共6页
目的探讨舒筋健腰丸联合斜外侧椎间融合术(OLIF)一期经皮椎弓根螺钉治疗退行性腰椎滑脱的临床疗效。方法选取2018年7月—2019年9月于武汉市中医医院接受OLIF联合后路经皮椎弓根螺钉治疗的69例退行性腰椎滑脱患者,随机分为观察组34例及... 目的探讨舒筋健腰丸联合斜外侧椎间融合术(OLIF)一期经皮椎弓根螺钉治疗退行性腰椎滑脱的临床疗效。方法选取2018年7月—2019年9月于武汉市中医医院接受OLIF联合后路经皮椎弓根螺钉治疗的69例退行性腰椎滑脱患者,随机分为观察组34例及对照组35例,2组均给予常规OLIF围术期处理,在此基础上观察组口服舒筋健腰丸,对照组口服模拟剂。比较术前及术后1个月2组患者NRS评分、Oswestry功能障碍指数(ODI)、健康相关生命质量评分(HRQoLs)、血清肿瘤坏死因子(TNF-α)、高迁移率族蛋白-1(HMGB-1)水平变化。结果与术前比较,术后1个月2组患者NRS评分、ODI评分均明显降低(P均<0.05),观察组显著低于对照组(P均<0.05);2组HRQoLs均显著升高(P均<0.05),观察组显著高于对照组(P<0.05);2组血清TNF-α及HMGB-1水平均显著下降(P均<0.05),且观察组明显低于对照组(P均<0.05)。结论OLIF一期经皮椎弓根螺钉治疗退行性腰椎滑脱疗效确切,联合舒筋健腰丸口服治疗疗效优于单纯手术治疗,可抑制炎症反应,减轻疼痛,进一步改善术后腰椎功能及生活质量,无明显不良反应。 展开更多
关键词 舒筋健腰丸 斜外侧椎间融合术 腰椎滑脱
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Present Situation Analysis and High-quality Development Countermeasures of Wadi Sheep Industry in Lubei Region
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作者 Shijin GUO Bing ZHANG +13 位作者 ling MO Xiaoliang WANG Jianjun WANG Lu GUO Jian ZHAO Xin li Weiqin MENG Pengfei MAO Shuguang li Shiyun TANG Shijun FU feng li Wenjian MA Jinliang WANG 《Agricultural Biotechnology》 2025年第1期13-18,共6页
This paper systematically analyzed the development status of sheep industry in Lubei region,and comprehensively expounded the scale and distribution of key industries,breed resources and genetic characteristics,feedin... This paper systematically analyzed the development status of sheep industry in Lubei region,and comprehensively expounded the scale and distribution of key industries,breed resources and genetic characteristics,feeding management status,disease prevention and control and veterinary services,and sheep product processing and sales.The research shows that the sheep industry in Lubei region has formed a certain scale,but there are some problems such as intensified resource and environmental constraints,unreasonable industrial structure,insufficient scientific and technological innovation capacity and market competitiveness to be improved.In view of these problems,this paper put forward some countermeasures and suggestions to promote the high-quality development of the industry,including establishing forage and feed system,promoting the adjustment and optimization of industrial structure,strengthening scientific and technological innovation and talent cultivation and introduction,and enhancing brand influence and market competitiveness,providing useful reference for the sustainable development of sheep industry in Lubei region. 展开更多
关键词 Wadi Sheep Industrial status quo High quality Development countermeasures PROSPECT
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Integrative transcriptomic and proteomic analysis reveals that SERPING1 inhibits neuronal proliferation via the CaMKII-CREB-BDNF pathway in schizophrenia
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作者 feng li Xing Ren +3 位作者 Jia-Xiu liu Tian-Dao Wang Bi Wang Xiao-Bin Wei 《World Journal of Psychiatry》 2025年第2期193-208,共16页
BACKGROUND Schizophrenia(SZ),a chronic and widespread brain disorder,presents with complex etiology and pathogenesis that remain inadequately understood.Despite the absence of a universally recognized endophenotype,pe... BACKGROUND Schizophrenia(SZ),a chronic and widespread brain disorder,presents with complex etiology and pathogenesis that remain inadequately understood.Despite the absence of a universally recognized endophenotype,peripheral blood mononuclear cells(PBMCs)serve as a robust model for investigating intracellular alterations linked to SZ.AIM To preliminarily investigate potential pathogenic mechanisms and identify novel biomarkers for SZ.METHODS PBMCs from SZ patients were subjected to integrative transcriptomic and proteomic analyses to uncover differentially expressed genes(DEGs)and differentially expressed proteins while mapping putative disease-associated signaling pathways.Key findings were validated using western blot(WB)and real-time fluorescence quantitative PCR(RT-qPCR).RNAi-lentivirus was employed to transfect rat hippocampal CA1 neurons in vitro,with subsequent verification of target gene expression via RT-qPCR.The levels of neuronal conduction proteins,including calmodulin-dependent protein kinase II(caMKII),CREB,and BDNF,were assessed through WB.Apoptosis was quantified by flow cytometry,while cell proliferation and viability were evaluated using the Cell Counting Kit-8 assay.RESULTS The integration of transcriptomic and proteomic analyses identified 6079 co-expressed genes,among which 25 DEGs were significantly altered between the SZ group and healthy controls.Notably,haptoglobin(HP),lactotransferrin(LTF),and SERPING1 exhibited marked upregulation.KEGG pathway enrichment analysis implicated neuroactive ligand-receptor interaction pathways in disease pathogenesis.Clinical sample validation demonstrated elevated protein and mRNA levels of HP,LTF,and SERPING1 in the SZ group compared to controls.WB analysis of all clinical samples further corroborated the significant upregulation of SERPING1.In hippocampal CA1 neurons transfected with lentivirus,reduced SERPING1 expression was accompanied by increased levels of CaMKII,CREB,and BDNF,enhanced cell viability,and reduced apoptosis.CONCLUSION SERPING1 may suppress neural cell proliferation in SZ patients via modulation of the CaMKII-CREB-BDNF signaling pathway. 展开更多
关键词 TRANSCRIPTOMICS Proteomics SCHIZOPHRENIA SERPING1 Pathogenesis
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Crystal growth kinetics of single-crystal Ni-rich layered cathodes for high-energy lithium-ion batteries
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作者 feng li Yu-hang TIAN +5 位作者 Lu-xia GE Sheng-long FAN Mao-sheng GONG Ke FAN Pei-yu HOU Xian-qi WEI 《Transactions of Nonferrous Metals Society of China》 2025年第6期1975-1986,共12页
The effects of synthesis conditions,especially the heating rate,on the reaction kinetics of Ni-rich cathodes were systematically studied.The growth rate of Ni-rich oxide increases continuously as the heating rate incr... The effects of synthesis conditions,especially the heating rate,on the reaction kinetics of Ni-rich cathodes were systematically studied.The growth rate of Ni-rich oxide increases continuously as the heating rate increases.Ab initio molecular dynamics simulations demonstrate that a high heating rate induces anabatic oscillations,indicating a decrease in thermodynamic stability and a tendency for the crystal surface to undergo reconstruction.The presence of an intermediate phase at the grain boundary amplifies atomic migration-induced interface fusion and consequently augments crystal growth kinetics.However,the excessively high heating rate aggravates the Li+/Ni2+mixing in the Ni-rich cathode.The single-crystal Ni-rich cathode exhibits enhanced structural/thermal stability but a decreased specific capacity and rate performance compared with its polycrystalline counterpart. 展开更多
关键词 lithium-ion battery Ni-rich cathode single crystal growth kinetics heating rate
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Unusual tensile strengths and strain-hardening behaviors and their structural correlation of Mg-RE solid solution
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作者 Wenbo Luo Rongsheng Bai +7 位作者 Zhilei Yu Xiuzhu Han Tong Guo Zhiyong Xue Chen Wen Mingyue Zheng feng li Zhihao lin 《Journal of Magnesium and Alloys》 2025年第8期4032-4044,共13页
This study systematically investigates the unusual tensile mechanical behavior of Mg-RE solid solution(SS)alloys,exhibiting anomalous tensile strengths(ATS)and an enhanced strain-hardening rate at high temperature.Bot... This study systematically investigates the unusual tensile mechanical behavior of Mg-RE solid solution(SS)alloys,exhibiting anomalous tensile strengths(ATS)and an enhanced strain-hardening rate at high temperature.Both the peak ultimate tensile strength(UTS)and tensile yield strength(TYS)values occur at 150-200℃,which are 12-50%higher compared to those at room temperature(RT).Meanwhile,the strain-hardening rate increases with the temperature rising from RT to 200℃ during the plastic deformation process.The results reveal that the formation of stacking faults(SFs)and the locking of dislocations,particularly immobile (c) partial dislocations,enhance resistance to plastic deformation,leading to higher strengths at high temperature.Furthermore,the interactivity between SFs and (c+a) dislocations intensify with rising of temperature.The presence of RE atoms in the SS plays a critical role in this unique mechanical behavior,as they preferentially occupy non-basal planes rather than basal planes,thereby reducing the stacking fault(SF)formation energy.This study provides new insights into the high-temperature strengthening mechanisms of Mg-RE based alloys,offering potential guidance for the design of advanced lightweight materials with superior mechanical properties. 展开更多
关键词 Anomalous tensile strength Mg-RE alloy Solid solution HEAT-RESISTANCE Molecular dynamics
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Engineering the diphasic Li-rich Mn-based composite with alleviated Jahn-Teller effect for high-energy Li-ion batteries
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作者 feng li Jia-Cheng li +4 位作者 Mao-Sheng Gong Ze-Zhou lin Xuan-Ming Chang Mo-Han Dong Pei-Yu Hou 《Rare Metals》 2025年第5期2945-2957,共13页
The unique oxygen stacking sequence of O2-type structures restricts the irreversible transition metal movement into Li vacancies for the delithiated Li-rich layered oxides(LLOs)and maintains outstanding voltage stabil... The unique oxygen stacking sequence of O2-type structures restricts the irreversible transition metal movement into Li vacancies for the delithiated Li-rich layered oxides(LLOs)and maintains outstanding voltage stability.However,the ion-exchange synthesis promotes the Mn-ion valence reduction and aggravates the Jahn-Teller(J-T)distortion alongside disproportionation.Since the main oxidation state of the Mn ions is+4 in the traditional O3-type LLOs,synergistic effects of the O2-type and O3-type structures are expected in the O2/O3 diphasic Li-rich material.Herein,O2/O3 biphasic intergrowth LLOs were rationally designed,and the synergic optimization of the biphasic structure was planned to retard the J-T effect.The O2/O3 intergrowth nature was confirmed,and the percentages of the O2 and O3 phases were 56%and 44%,respectively.Density functional theory calculations demonstrated that the Mn^(2+)(EC)sheath had a remarkably lower energy barrier than the Li^(+)(EC)sheath.This finding suggests that Mn^(2+)ions that are dissolved into the electrolyte accelerate the electrolyte oxidization,so the deposition of the cathode electrolyte interface for pristine O2-LLOs causes a high electrochemical impedance.The designed O2/O3 biphasic LLOs boost the capacity stability and suppress the voltage drop upon repeated Li^(+)de-intercalation.The phase regulation strategy offers great potential for developing low-cost LLOs with enhanced structural stability for advanced Li-ion batteries. 展开更多
关键词 Li-ion battery Li-rich cathode Biphasic composite Jahn-Teller effect Structural stability
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Dual-ligand engineering over Au-based catalyst for efficient acetylene hydrochlorination
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作者 Yongsheng Xu lisha Yao +7 位作者 Jian li Yanzhao Dong Dongyang Xie Miaomiao Zhang feng li Yunsheng Dai Jinli Zhang Haiyang Zhang 《Chinese Chemical Letters》 2025年第3期422-426,共5页
Introducing ligand into the surface of gold(Au)-based catalyst has been recognized as an efficient strategy to enhance the performance of catalyst in acetylene hydrochlorination reaction.However,due to the multifactor... Introducing ligand into the surface of gold(Au)-based catalyst has been recognized as an efficient strategy to enhance the performance of catalyst in acetylene hydrochlorination reaction.However,due to the multifactorial deactivation,the usage of single type of ligand has limitations on the performance improvement.In this work,two types of ligands including a molecular 2-methylimidazole and an ionic cetrimonium are selected to protect Au^(n+)species.After kinetics analysis,advanced characterization,and density functional theory simulation,we demonstrate the optimal interaction model between two ligands and Au species:Two 2-methylimidazole molecules are coordinated with high-valent Au species while cetrimonium is interacted via electrostatic interaction.Except the synergistic effect in the decrease of Au species reduction and agglomeration,the existence of molecular ligand greatly increases the adsorption of hydrogen chloride while the ionic ligand significantly inhibits the deposition of coke.Due to the positive effect of dual-ligands,we achieved 97.1%of acetylene conversion and 0.29 h^(−1) of deactivation rate under high gas hourly space velocity of acetylene.This work establishes a foundation to explore the property-activity relationships in Au-based catalyst via ligand engineering. 展开更多
关键词 Acetylene hydrochlorination Gold-based catalyst Dual-ligand engineering Catalytic performance enhancement
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“计算机辅助工业设计-Autodesk AliasStudio”在线课程与线下教学结合探索 被引量:2
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作者 张杨 方迪 冯莉 《科教文汇》 2019年第22期79-81,106,共4页
本文对“计算机辅助工业设计”课程线上与线下教学结合进行了一些有效探讨。在线上教学上根据课程特色,在课堂内实现问题式、项目式、案例式、研讨式“翻转课堂”的教学设计,并将这些教学设计与线下教学的问题相关联。利用在线课程学习... 本文对“计算机辅助工业设计”课程线上与线下教学结合进行了一些有效探讨。在线上教学上根据课程特色,在课堂内实现问题式、项目式、案例式、研讨式“翻转课堂”的教学设计,并将这些教学设计与线下教学的问题相关联。利用在线课程学习调动了学生的学习热情,满足学生多样化、个性化的学习需求,并且形成有效地目标达成路径及能够确认目标达成的过程化考核记录。 展开更多
关键词 工业设计 在线课程 教学结合 教学设计
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工业设计专业“计算机辅助工业设计-Autodesk AliasStudio”在线课程设计方法研究 被引量:1
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作者 张杨 方迪 冯莉 《科教文汇》 2018年第16期76-78,共3页
"计算机辅助工业设计"课程是一门使学生具备理论知识与实践技能综合能力的课程,对于学生在产品效果表现应用上非常重要。本文对目前课程教学中存在的问题进行了分析,根据课程特点对本课程的在线课程建设方法进行了研究,研究... "计算机辅助工业设计"课程是一门使学生具备理论知识与实践技能综合能力的课程,对于学生在产品效果表现应用上非常重要。本文对目前课程教学中存在的问题进行了分析,根据课程特点对本课程的在线课程建设方法进行了研究,研究中从以学生角度出发进行了课程设计,设置充足、完整及系统的教学资源,使教师与学生通过在线课程形成良好的互动形式,建立"翻转课堂"教学模式,从而实现教学质量不断提升和教学资源的合理利用。 展开更多
关键词 工业设计专业 在线课程 教学方法 设计
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检测猪鼻支原体抗原的ELISA方法的建立及其应用 被引量:1
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作者 朱红振 危艳武 +6 位作者 黄立平 刘丹 夏德利 吴洪丽 边海桥 冯力 刘长明 《中国兽医科学》 CAS CSCD 北大核心 2019年第7期828-833,共6页
为了建立检测猪鼻支原体(Mhr)抗原的ELISA方法,本研究采用杂交瘤技术制备了抗Mhr菌体的特异性单克隆抗体(MAb),经亲和层析纯化后标记辣根过氧化物酶(HRP),建立了一种能够检测Mhr抗原的ELISA方法。ELISA反应条件优化结果为:HRP标记的MAb... 为了建立检测猪鼻支原体(Mhr)抗原的ELISA方法,本研究采用杂交瘤技术制备了抗Mhr菌体的特异性单克隆抗体(MAb),经亲和层析纯化后标记辣根过氧化物酶(HRP),建立了一种能够检测Mhr抗原的ELISA方法。ELISA反应条件优化结果为:HRP标记的MAb最适稀释度为1∶1000,该方法的批内和批间变异系数均小于6%,经超声波处理Mhr抗原效果更佳,最低抗原检出量为25ng。用该方法对已知猪肺炎支原体(Mhp)、猪圆环病毒2型(PCV2)抗原检测无交叉反应。本研究建立的检测Mhr抗原的ELISA方法具有良好的特异性、敏感性和重复性,可为Mhr体外培养物抗原定量检测提供可靠的技术手段。 展开更多
关键词 猪鼻支原体 单克隆抗体 抗原检测 ELISA
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油葵(Helianthus annuus)HaDGAT1基因的克隆与生物信息学分析 被引量:1
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作者 刘文豪 卢天信 +4 位作者 成丽颖 吕新华 冯丽 周至铭 孙黎 《分子植物育种》 CAS CSCD 北大核心 2019年第20期6619-6625,共7页
油葵(Helianthus annuus L.)种子富含不饱和脂肪酸,主要是亚油酸。亚油酸是人体必需的脂肪酸,能降低血液胆固醇,预防动脉粥样硬化,发挥抗癌作用。二酰基甘油酰基转移酶(diacylglycerol acyltrabsferase,DGAT)作为一种限速酶在油葵合成... 油葵(Helianthus annuus L.)种子富含不饱和脂肪酸,主要是亚油酸。亚油酸是人体必需的脂肪酸,能降低血液胆固醇,预防动脉粥样硬化,发挥抗癌作用。二酰基甘油酰基转移酶(diacylglycerol acyltrabsferase,DGAT)作为一种限速酶在油葵合成三酰甘油的过程中发挥重要作用。本研究通过对油葵种子转录组测序,利用PCR方法成功克隆得到一个DGAT1基因的c DNA序列,命名为HaDGAT1。对油葵HaDGAT1基因进行生物信息学分析,发现油葵HaDGAT1基因CDS全长1 440 bp,共编码479个氨基酸,所编码蛋白的分子量为55.740 kD,理论等电点为9.24。油葵Ha DGAT1为疏水性蛋白,亚细胞定位预测在内质网膜上。该蛋白的二级结构中α螺旋(44.05%),β转角(1.88%),延伸链(13.36%)和无规则卷曲(40.71%),与预测的蛋白质三级结构一致。本研究为进一步深入了解HaDGAT1基因的功能和调控机制和利用基因工程技术调节油葵脂肪酸的含量、改良油葵油的品质提供了理论依据。 展开更多
关键词 油葵(Helianthus annuus L.) HaDGAT1 基因克隆 生物信息学
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Effects of Wen Dan Tang on insomnia-related anxiety and levels of the brain-gut peptide Ghrelin 被引量:16
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作者 liye Wang Yuehan Song +8 位作者 feng li Yan liu Jie Ma Meng Mao fengzhi Wu Ying Wu Sinai li Binghe Guan Xiaolan liu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第2期205-212,共8页
Ghrelin, a brain-gut peptide that induces anxiety and other abnormal emotions, contributes to the effects of insomnia on emotional behavior. In contrast, the traditional Chinese Medi- cine remedy Wen Dan Tang reduces ... Ghrelin, a brain-gut peptide that induces anxiety and other abnormal emotions, contributes to the effects of insomnia on emotional behavior. In contrast, the traditional Chinese Medi- cine remedy Wen Dan Tang reduces insomnia-related anxiety, which may perhaps correspond to changes in the brain-gut axis. This suggests a possible relationship between Wen Dan Tan^s pharmacological mechanism and the brain-gut axis. Based on this hypothesis, a sleep-deprived rat model was induced and Wen Dan Tang was administered using oral gavage during model es- tablishment. Wen Dan Tang significantly reduced insomnia-related anxiety and prevented Ghrelin level decreases following sleep deprivation, especially in the hypothalamus. Increased expression of Ghrelin receptor mRNA in the hypothalamus was also observed, suggesting that reduced anxi- ety may be a result of Wen Dan Tan's regulation of Ghrelin-Ghrelin receptors. 展开更多
关键词 nerve regeneration Chinese Medicine Wen Dan Tang sleep deprivation ANXIETY GHRELIN Ghrelin receptor the National Natural Science Youth Foundation in China neural regeneration
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Choice for graphene as conductive additive for cathode of lithium-ion batteries 被引量:16
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作者 Ying Shi Lei Wen +2 位作者 Songfeng Pei Minjie Wu feng li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第3期19-26,共8页
Graphene is a promising conductive additive for the lithium-ion batteries(LIBs) and shows great potential especially with its fast development of the large scale fabrication technology. This work has explored the infl... Graphene is a promising conductive additive for the lithium-ion batteries(LIBs) and shows great potential especially with its fast development of the large scale fabrication technology. This work has explored the influence of the incorporation of graphenes prepared by three typical methods on the electrochemical performance of the LiCoO_2-based cathode focusing on the choice for the effective graphene as conductive additive for the cathode of LIBs. Through the comparison of the intrinsic characteristics of graphenes and the electrochemical performance of electrodes with graphene, it is found that graphene with low disorder degree and large size is not suitable for LiCoO_2 cathodes as conductive additive. Conversely, the graphene with oxygen functional groups, relatively low surface area and proper size displays much better electrochemical performance when it is used as conductive additive. This work also demonstrates the transmission mechanism for different graphenes as conductive additives in the LiCoO_2 materials, and further reveals that the conductivity of graphene is not the only factor as conductive additives, surface chemistry and sheet size of the graphene are also essential factors which greatly influence the electrochemical performance of electrode. In addition, when combined with Super P, only 1% graphene is enough to construct an efficient conductive network in the electrode. This study also gives a new sight on the practical application of graphene as conductive additive for high performance LIBs. 展开更多
关键词 GRAPHENE CONDUCTIVE additive LITHIUM-ION batteries LICOO2 CATHODE
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Synthesis and characterization of geopolymer from lunar regolith simulant based on natural volcanic scoria 被引量:15
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作者 Siqi ZHOU Xingyi ZHU +1 位作者 Chenghong LU feng li 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第1期144-159,共16页
In this study,a new GVS(Ground Volcanic Scoria)lunar regolith simulant was produced.The similarity between GVS and lunar soil was proved by comparison with Apollo lunar soil samples and other commercial lunar soil sim... In this study,a new GVS(Ground Volcanic Scoria)lunar regolith simulant was produced.The similarity between GVS and lunar soil was proved by comparison with Apollo lunar soil samples and other commercial lunar soil simulants.Then,GVS lunar regolith simulant was investigated as the source material for preparing geopolymer to produce building material for lunar colony construction.To study the possibility of preparing geopolymer from GVS lunar regolith simulant and the optimum activator formulation as well as the optimum curing conditions,alkaline activated GVS slurries with different mixing ratios based on an orthogonal test scheme were prepared.The geopolymer products based on GVS were characterized by flexural strength test,compressive strength test,X-ray fluorescence(XRF),X-ray diffraction(XRD),Fourier Transform Infrared Spectroscopy(FTIR),Scanning Electron Microscope coupled with Energy Dispersive Spectroscopy(SEM-EDS),29Si magic angle spinning-nuclear magnetic resonance(29Si MAS-NMR),and 27Al MAS-NMR.The experimental results indicate that changes in the mass ratio of sodium hydroxide and GVS and curing temperature have the most significant influence on the flexural strength and compressive strength,respectively.The GVS-based geopolymer can obtain the highest 28-day compressive strength and 28-day flexural strength up to 75.6 MPa and 6.3 MPa.Microstructural results imply that the changes of Si occurring in a variety of environments that explaining preliminarily about the reaction mechanism of GVS-based geopolymer.This study approves the feasibility of making a geopolymer derived from the GVS lunar regolith simulant and the potential utilization of geopolymer based on lunar regolith for construction of the lunar colony in future space exploration. 展开更多
关键词 GEOPOLYMER Lunar regolith simulant Mechanical properties Microstructure Moon colony Volcanic scoria
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Effects of 60-day NO_2 fumigation on growth,oxidative stress and antioxidative response in Cinnamomum camphora seedlings 被引量:10
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作者 Zhuo-mei CHEN Ying-xu CHEN +2 位作者 Guo-jian DU Xi-lin WU feng li 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2010年第3期190-199,共10页
Objective: To study the oxidative stress and antioxidative response of Cinnamomum camphora seedlings exposed to nitrogen dioxide (NO2) fumigation. Methods: Measurements were made up of the growth, chlorophyll cont... Objective: To study the oxidative stress and antioxidative response of Cinnamomum camphora seedlings exposed to nitrogen dioxide (NO2) fumigation. Methods: Measurements were made up of the growth, chlorophyll content, chlorophyll fluorescence, antioxidant system and lipid peroxidation of one-year-old C. camphora seedlings exposed to NO2 (0.1, 0.5, and 4 μl/L) fumigation in open top chambers over a period of 60 d. Results: After the first 30 d, 0.5 and 4.0 μl/L NO2 showed insignificant effects on the growth of C. camphora seedlings. However, exposure to 0.5 and 4.0 pilL NO2 for 15 d significantly reduced their chlorophyll content (P〈0.05), enhanced their malondialdehyde (MDA) content and superoxide dismutase (SOD) activity (P〈0.05), and also significantly reduced the maximal quantum yield of PSII in the dark [the ratio of variable fluorescence to maximal fluorescence (Fv/Fm)] (P〈0.05). In the latter 30 d, 0.5μl/L NO2 showed a positive effect on the vitality of the seedlings, which was reflected by a recovery in the ratio of Fv/Fm and chlorophyll content, and obviously enhanced growth, SOD activity, ascorbate (AsA) content and glutathione reductase (GR) activity (P〈0.05); 4.0 pilL NO2 then showed a negative effect, indicated by significant reductions in chlorophyll content and the ratio of Fv/Fm, and inhibited growth (P〈0.05). Conclusion: The results suggest adaptation of C. camphora seedlings to 60-d exposure to 0.1 and 0.5 μl/L NO2, but not to 60-d exposure to 4.0 pilL NO2 C. camphora seedlings may protect themselves from injury by strengthening their antioxidant system in response to NO2-induced oxidative stress. 展开更多
关键词 Cinnamomum camphora FUMIGATION GROWTH Chlorophyll content Chlorophyll fluorescence ANTIOXIDANT Lipid peroxidation
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Preparation and Characterization of High-Strength Geopolymer Based on BH-1 Lunar Soil Simulant with Low Alkali Content 被引量:18
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作者 Siqi Zhou Chenghong Lu +1 位作者 Xingyi Zhu feng li 《Engineering》 SCIE EI 2021年第11期1631-1645,共15页
The construction of a lunar base and habitation on the Moon has always been on researchers’minds.Building materials used in in situ lunar resources are of great significance for saving expensive space freight.In this... The construction of a lunar base and habitation on the Moon has always been on researchers’minds.Building materials used in in situ lunar resources are of great significance for saving expensive space freight.In this study,a new type of lunar soil simulant named Beihang(BH)-1 was developed.The chemical mineral composition and microstructure of BH-1 closely resemble those of real lunar soil,as verified by X-ray fluorescence spectroscopy(XRF),X-ray diffraction(XRD),scanning electron microscopy(SEM),and reflectance spectra.This research also synthesized a geopolymer based on BH-1 cured at simulated lunar atmospheric conditions.We also investigated the effect of supplementing aluminum(Al)sources on the enhancement of geopolymer strength based on BH-1.The rheological behavior of alkali-activated BH-1 pastes was determined for workability.XRF,XRD,Fourier transform infrared spectroscopy,SEM coupled with energy dispersive spectroscopy,and 27Al magic angle spinningnuclear magnetic resonance were used to characterize resulting geopolymers.Rheological test findings showed that the rheology of BH-1 pastes fits the Herschel–Bulkley model,and they behaved like a shear-thinning fluid.The results showed that the 28-day compressive strength of the BH-1 geopolymer was improved by up to 100.8%.Meanwhile,the weight of additives required to produce per unit strength decreased,significantly reducing the mass of materials transported from the Earth for the construction of lunar infrastructure and saving space transportation costs.Microscopic analyses showed that the mechanism to improve the mechanical properties of the BH-1 geopolymer by adding an additional Al source enhances the replacement of silicon atoms by Al atoms in the silicon–oxygen group and generates a more complete and dense amorphous gel structure. 展开更多
关键词 Space exploration Lunar base GEOPOLYMER Lunar soil simulant RHEOLOGY
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