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Inhibitory effect of Fuzheng Yiliuyin in combination with chemotherapeutics on human gastric carcinoma cell strain 被引量:3
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作者 yi liu Rui Wang +2 位作者 Gen-Quan Qiu Ke-Jun Nan Xi-Cai Sun 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第25期4071-4073,共3页
AIM: To study the inhibitory effects of Fuzheng Yiliuyin (Decoction for Suppressing Tumors by Strengthening the Body Resistance) in combination with chemotherapeutics on human gastric carcinoma cell strain. METHODS... AIM: To study the inhibitory effects of Fuzheng Yiliuyin (Decoction for Suppressing Tumors by Strengthening the Body Resistance) in combination with chemotherapeutics on human gastric carcinoma cell strain. METHODS: Fuzheng Yiliuyin (ZY) combined with various kinds of chemotherapeutics was put into two kinds of cultivated human gastric carcinoma cell strains, then its inhibitory effects on human gastric carcinoma cell strains were determind by the MTT method. Flow cytorneter was used to assay the apoptosis rate, and the ultrastructure of gastric carcinoma cells was observed under transmission electron microscope. RESULTS: Obvious apoptosis was seen in gastric carcinoma cells after treatment with ZY for 72 h. ZY and chemical drugs had synergistic inhibition effects on the cultivated gastric carcinoma cells, but the effects were different on various cell strains. The inhibitory effects of ZY could be strengthened by cytotoxic action and apoptosis. ZY combined with tluorouracil, etoposide and cisplatin (EFP) chemotherapeutics had better inhibitory effects on SGC-7901, while ZY combined with EFP or with DDP chemotherapeutics had better inhibitory effects than other drugs on MGC-803. CONCLUSION: ZY induces apoptosis and inhibits the growth of gastric carcinoma cells. ZY has the synergistic function of chemotherapeutics. 展开更多
关键词 Human gastric carcinoma cell strain Traditional Chinese medicine Chemotherapeutics
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地中海饮食对肺癌相关性影响的研究进展
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作者 高明朗 赖凯 +3 位作者 卢子龙 刘毅 李宁 耿庆 《中国肺癌杂志》 CAS CSCD 北大核心 2024年第4期299-305,共7页
肺癌是当今世界十大死因之一,它以其高死亡率令全世界深感忧愁。在现代医学研究中,研究人员正致力于深入挖掘肺癌发生和发展的不同影响因素,以降低其发病率,提高肺癌的治疗成功率,改善肺癌患者的预后。地中海饮食(Mediterranean diet,MD... 肺癌是当今世界十大死因之一,它以其高死亡率令全世界深感忧愁。在现代医学研究中,研究人员正致力于深入挖掘肺癌发生和发展的不同影响因素,以降低其发病率,提高肺癌的治疗成功率,改善肺癌患者的预后。地中海饮食(Mediterranean diet,MD)是一种特殊的膳食结构,它以吃蔬菜、水果、粗粮、豆类和低脂鱼类为主,被报道具有抗炎、抗氧化、降脂等作用。近年来的研究发现,MD可能会在一定程度上预防肺癌,并对其发病和进展产生重要影响。本文旨在对相关文献进行综述,总结及分析性地探讨MD对肺癌发病及进展的影响,从而更好地为预防和治疗肺癌提供研究方向。 展开更多
关键词 肺肿瘤 地中海饮食 饮食 健康 蔬菜 水果
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Correlation between the gut microbiome and neurodegenerative diseases:a review of metagenomics evidence 被引量:5
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作者 Xiaoyan liu yi liu +7 位作者 Junlin liu Hantao Zhang Chaofan Shan yinglu Guo Xun Gong Mengmeng Cui Xiubin Li Min Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期833-845,共13页
A growing body of evidence suggests that the gut microbiota contributes to the development of neurodegenerative diseases via the microbiota-gut-brain axis.As a contributing factor,microbiota dysbiosis always occurs in... A growing body of evidence suggests that the gut microbiota contributes to the development of neurodegenerative diseases via the microbiota-gut-brain axis.As a contributing factor,microbiota dysbiosis always occurs in pathological changes of neurodegenerative diseases,such as Alzheimer’s disease,Parkinson’s disease,and amyotrophic lateral sclerosis.High-throughput sequencing technology has helped to reveal that the bidirectional communication between the central nervous system and the enteric nervous system is facilitated by the microbiota’s diverse microorganisms,and for both neuroimmune and neuroendocrine systems.Here,we summarize the bioinformatics analysis and wet-biology validation for the gut metagenomics in neurodegenerative diseases,with an emphasis on multi-omics studies and the gut virome.The pathogen-associated signaling biomarkers for identifying brain disorders and potential therapeutic targets are also elucidated.Finally,we discuss the role of diet,prebiotics,probiotics,postbiotics and exercise interventions in remodeling the microbiome and reducing the symptoms of neurodegenerative diseases. 展开更多
关键词 biomarker diet pattern gut microbiota gut-brain axis METAGENOMICS mitochondrial dysfunction multi-omics neurodegenerative disease NEUROINFLAMMATION probiotic
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Natural sources,refined extraction,biosynthesis,metabolism,and bioactivities of dietary polymethoxyflavones(PMFs) 被引量:2
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作者 Renyou Gan yi liu +6 位作者 Hang Li Yu Xia Huan Guo Fang Geng Qiguo Zhuang Huabin Li Dingtao Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期27-49,共23页
Polymethoxyflavones(PMFs)are a type of uncommon dietary flavonoids,characterized by more than one methoxy group,which exist in limited plant species,like Citrus species and Kaempferia parviflora.In addition,different ... Polymethoxyflavones(PMFs)are a type of uncommon dietary flavonoids,characterized by more than one methoxy group,which exist in limited plant species,like Citrus species and Kaempferia parviflora.In addition,different PMFs,such as nobiletin,sinensetin,tangeretin,and casticin,have been isolated from these natural sources.PMFs have received increasing attention due to their multiple bioactivities,such as antioxidant,anti-inflammatory,anti-cancer,metabolic regulatory,immunoregulatory,neuroprotective,and skin protective effects.These bioactivities of PMFs should be associated with the regulation of critical molecular targets and the interaction with gut microbiota.In order to provide a comprehensive and updated review of PMFs,their natural sources,refined extraction,biosynthesis,metabolism,and bioactivities are summarised and discussed,with the emphasis on the molecular mechanisms of PMFs on regulating different chronic diseases.Overall,PMFs may be promising flavonoids to the forefront of nutraceuticals for the prevention and/or treatment of certain human chronic diseases. 展开更多
关键词 NOBILETIN O-METHYLTRANSFERASES Gut microbiota BIOACTIVITIES Molecular mechanism
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基于激光雕刻石墨烯电极的伏安法实验教学新方案
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作者 周桢林 陈思元 +2 位作者 刘仪 胡成国 赵发琼 《大学化学》 CAS 2024年第2期358-370,共13页
伏安法是仪器分析课程的重要章节和教学难点,其现有实验教学方案在理论融合和应用拓展等方面存在不足。本文通过引入较为前沿的激光雕刻石墨烯电极体系,丰富内容如扩散电流理论和电催化现象模拟,延伸应用如奶粉香兰素检测,帮助学生深入... 伏安法是仪器分析课程的重要章节和教学难点,其现有实验教学方案在理论融合和应用拓展等方面存在不足。本文通过引入较为前沿的激光雕刻石墨烯电极体系,丰富内容如扩散电流理论和电催化现象模拟,延伸应用如奶粉香兰素检测,帮助学生深入理解方法的基本原理、研究动向和应用价值。实验综合成本低、电极可批量制备,适合教学开展。 展开更多
关键词 伏安法 实验教学 激光雕刻石墨烯电极
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构筑富含磷空位缺陷的磷化钯催化剂实现高效和抗CO毒化的碱性氢氧化反应
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作者 杨玉婷 石路岩 +5 位作者 梁沁睿 刘奕 董家新 Tayirjan Taylor Isimjan 王宝 杨秀林 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第1期176-187,共12页
碱性阴离子交换膜燃料电池(AEMFCs)可以直接将氢的化学能转化为电能,被认为是新兴绿色氢经济的基石技术.但其阳极氢氧化反应(HOR)动力学缓慢,严重依赖于Pt基催化剂.由于Pt基催化剂极易被CO毒化、动力学过程复杂以及价格昂贵,极大限制了... 碱性阴离子交换膜燃料电池(AEMFCs)可以直接将氢的化学能转化为电能,被认为是新兴绿色氢经济的基石技术.但其阳极氢氧化反应(HOR)动力学缓慢,严重依赖于Pt基催化剂.由于Pt基催化剂极易被CO毒化、动力学过程复杂以及价格昂贵,极大限制了其商业化应用.因此,亟需开发高效、稳定和抗CO毒化能力强的新型HOR催化剂.Pd具有与Pt相似的氢键结合能,并且比Pt储量丰富,有望成为实现HOR的候选催化剂.然而,Pd的本征催化活性和Pt相比仍有很大差距.近年来,磷化钯因具有功能多样性和高催化活性被广泛关注.此外,缺陷工程可以有效调控催化剂的表面结构,改善中间体的吸附强度,提高催化剂的催化活性.因此,构建富含缺陷的磷化钯催化剂有望提高其HOR的性能.然而,该方向研究较少,反应机理尚不清楚.因此,阐明空位缺陷对于提高磷化钯催化剂HOR性能的作用机制,对促进AEMFCs电催化反应具有重要意义.本文通过溶胶-凝胶法以及低温磷化策略合成了一种碗状半球结构的富含磷空位Pd3P@C(V_(p)-Pd_(3)P@C)催化剂,并用于碱性HOR.在磷化过程中,通过调整Pd前驱体和磷源比例以及煅烧温度,在碳碗状半球载体上合成具有不同晶相组成(Pd/Pd_(3)P@C,Pd_(3.20)P_(12)@C,Pd_(3)P@C,和Pd_(5)P_(2)@C)的Pd_(x)P_(y)@C催化剂.扫描电镜和透射电镜证实了催化剂为碗状半球形貌.利用电子顺磁共振波谱研究了Pd_(x)P_(y)@C催化剂的磷空位浓度,结果表明,Pd/P比例为1:3时,在350℃下煅烧得到的Vp-Pd_(3)P@C具有最高的磷空位浓度.X射线光电子能谱证实了磷空位促进了d-p轨道杂化,增强了Pd和磷之间的电子相互作用.电化学测试结果表明,Vp-Pd_(3)P@C具有最高的HOR性能,Vp-Pd_(3)P@C在50 mV的质量活性为1.66 mAμg_(Pd)^(–1),交换电流密度为3.2 mA cm^(–2),优于Pd3P(0.45 mAμg_(Pd)^(-1),1.78 mA cm^(–2))和商业Pt/C(0.3 mAμg_(Pd)^(-1),2.29 mA cm^(–2)).同时,该催化剂在50 mV的电位下能稳定运行20 h.此外,即使在CO浓度高达1000 ppm时,Vp-Pd_(3)P@C催化剂仍表现出较好的HOR活性.紫外光电子能谱证实了Vp-Pd_(3)P@C中的Pd原子呈现缺电子状态,这不利于Pd 4d轨道对CO 2π^(*)轨道的电子反馈,降低了Pd和CO的键合强度,进而减弱了Pd对CO分子的吸附,从而增强了其抗CO中毒的能力.密度泛函理论计算结果表明,相较于磷空位浓度较少的Pd_(3)P@C催化剂,富含磷空位缺陷的Vp-Pd_(3)P@C催化剂能够优化和平衡反应中间体(Hads和OHads)的吸附强度,使速率决定步骤从H_(2)O^(*)的解吸转换到H_(2)O的形成,促进了Volmer反应(Hads+OHads→H_(2)O+2^(*)sites)的进行,进而提升了催化活性.系统实验和表征结果表明,Vp-Pd_(3)P@C较好的HOR性能可归因于以下3个因素:(1)空心碗状结构大大地增加了固-液-气三相接触点,加速了HOR的传质过程;(2)磷空位产生的局部反应活性和有利的电子结构优化了Hads和OHads的吸附强度,极大地促进了Volmer步骤;(3)丰富的磷空位打破了原有的周期性晶体结构,形成了新的电子结构,有效地抑制了电子从Pd 4d轨道到CO 2π^(*)轨道的反馈,提高了Vp-Pd_(3)P@C对CO的耐受能力.综上,本文通过缺陷工程策略调控了Vp-Pd_(3)P@C中活性位点与HOR关键中间体的相互作用,明确了空位缺陷浓度与HOR活性之间的构效关系.并从碱性HOR反应机理,CO分子与金属催化剂的轨道相互作用以及结构设计三个方面总结了高效和稳定的HOR催化剂的设计原则.目前,由于界面环境的复杂性和缺乏原位技术,催化剂表面上痕量中间体的光谱信息难以获得,未来可在开发原位技术监测HOR过程中间体和催化剂的组分变化方面做出更多的努力,以促进AEMFCs的商业化应用. 展开更多
关键词 氢氧化反应 CO耐受性 磷空位 V_(p)-Pd_(3)P@C 碗状半球
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Process and performance of DAAF microspheres prepared by continuous integration from synthesis to spherical coating based on microfluidic system
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作者 Bidong Wu Jiahui Shi +5 位作者 Mengsen Wei Rui Zhu yi liu Jinqiang Zhou Chongwei An Jingyu Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期629-643,共15页
In order to improve the energy output consistency of 3, 3’-diamino-4, 4’-azoxyfurazan(DAAF) in the new insensitive booster and the safety and efficiency in the preparation process, a continuous preparation system of... In order to improve the energy output consistency of 3, 3’-diamino-4, 4’-azoxyfurazan(DAAF) in the new insensitive booster and the safety and efficiency in the preparation process, a continuous preparation system of DAAF from synthesis to spherical coating was designed and established in this paper, which combined ultrasonic micromixing reaction with microdroplet globular template. In the rapid micromixing stage, the microfluidic mixing technology with ultrasonic was used to synergistically strengthen the uniform and rapid mass transfer mixing reaction between raw materials to ensure the uniformity of DAAF particle nucleation-growth, and to prepare high-quality DAAF crystals with uniform structure and morphology and concentrated particle size distribution. In the microdroplet globular template stage, the microfluidic droplet technology was used to form a droplet globular template with uniform size under the shear action of the continuous phase of the dispersed phase solution containing DAAF particles and binder. The size of the droplet template was controlled by adjusting the flow rate ratio between the continuous phase and the dispersed phase. In the droplet globular template, with the diffusion of the solvent in the dispersed phase droplets, the binder precipitates to coat the DAAF into a ball, forming a DAAF microsphere with high sphericity, narrow particle size distribution and good monodispersity. The problem of discontinuity and DAAF particle suspension in the process was solved, and the coating theory under this process was studied. DAAF was coated with different binder formulations of fluororubber(F2604), nitrocellulose(NC) and NC/glycidyl azide polymer(GAP), and the process verification and evaluation of the system were carried out. The balling effects of large, medium and small droplet templates under different binder formulations were studied. The scanning electron microscope(SEM) results show that the three droplet templates under the three binder formulations exhibit good balling effect and narrow particle size distribution. The DAAF microspheres were characterized by powder X-ray diffraction(XRD), differential scanning calorimetry(DSC), thermo-gravimetric(TG) and sensitivity analyzer. The results showed that the crystal structure of DAAF did not change during the process, and the prepared DAAF microspheres had lower decomposition temperature and lower mechanical sensitivity than raw DAAF. The results of detonation parameters show that the coating of DAAF by using the above three binder formulations will not greatly reduce the energy output of DAAF, and has comparable detonation performance to raw DAAF. This study proves an efficient and safe continuous system from synthesis to spherical coating modification of explosives, which provides a new way for the continuous, safe and efficient preparation of spherical explosives. 展开更多
关键词 DAAF Micromixing technology Microdroplet technology SYNTHESIS Spherical coating Continuousization
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Vibration Control of the Rail Grinding Vehicle with Abrasive Belt Based on Structural Optimization and Lightweight Design
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作者 Wengang Fan Shuai Zhang +2 位作者 Zhiwei Wu yi liu Jiangnan Yu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期311-337,共27页
As a new grinding and maintenance technology,rail belt grinding shows significant advantages in many applications The dynamic characteristics of the rail belt grinding vehicle largely determines its grinding performan... As a new grinding and maintenance technology,rail belt grinding shows significant advantages in many applications The dynamic characteristics of the rail belt grinding vehicle largely determines its grinding performance and service life.In order to explore the vibration control method of the rail grinding vehicle with abrasive belt,the vibration response changes in structural optimization and lightweight design are respectively analyzed through transient response and random vibration simulations in this paper.Firstly,the transient response simulation analysis of the rail grinding vehicle with abrasive belt is carried out under operating conditions and non-operating conditions.Secondly,the vibration control of the grinding vehicle is implemented by setting vibration isolation elements,optimizing the structure,and increasing damping.Thirdly,in order to further explore the dynamic characteristics of the rail grinding vehicle,the random vibration simulation analysis of the grinding vehicle is carried out under the condition of the horizontal irregularity of the American AAR6 track.Finally,by replacing the Q235 steel frame material with 7075 aluminum alloy and LA43M magnesium alloy,both vibration control and lightweight design can be achieved simultaneously.The results of transient dynamic response analysis show that the acceleration of most positions in the two working conditions exceeds the standard value in GB/T 17426-1998 standard.By optimizing the structure of the grinding vehicle in three ways,the average vibration acceleration of the whole car is reduced by about 55.1%from 15.6 m/s^(2) to 7.0 m/s^(2).The results of random vibration analysis show that the grinding vehicle with Q235 steel frame does not meet the safety conditions of 3σ.By changing frame material,the maximum vibration stress of the vehicle can be reduced from 240.7 MPa to 160.0 MPa and the weight of the grinding vehicle is reduced by about 21.7%from 1500 kg to 1175 kg.The modal analysis results indicate that the vibration control of the grinding vehicle can be realized by optimizing the structure and replacing the materials with lower stiffness under the premise of ensuring the overall strength.The study provides the basis for the development of lightweight,diversified and efficient rail grinding equipment. 展开更多
关键词 Vibration control Dynamic characteristics Structural optimization Lightweight design Modal analysis
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Surface deterioration dependent on the crystal facets of spinel LiNi_(0.5)Mn_(1.5)O_(4) cathode active material
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作者 Qian Li Yan Zhao +5 位作者 Jifu Zhu Wujiu Zhang yi liu Yaru Cui Chao Shen Keyu Xie 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期757-766,I0016,共11页
The spinel LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)cathode active materials(CAMs)are considered a promising alternative to commercially available cathodes such as layered and polyanion oxide cathodes,primarily due to their notab... The spinel LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)cathode active materials(CAMs)are considered a promising alternative to commercially available cathodes such as layered and polyanion oxide cathodes,primarily due to their notable safety and high energy density,particularly in their single-crystal type.Nevertheless,the industrial application of the LNMO CAMs is severely inhibited due to the interfacial deterioration and corrosion under proton-rich and high-voltage conditions.This study successfully designed and synthesized two typical types of crystal facets-exposed single-crystal LNMO CAMs.By tracking the electrochemical deterioration and chemical corrosion evolution,this study elucidates the surface degradation mechanisms and intrinsic instability of the LNMO,contingent upon their crystal facets.The(111)facet,due to its elevated surface energy,is found to be more susceptible to external attack compared to the(100)and(110)facets.Our study highlights the electrochemical corrosion stability of crystal plane engineering for spinel LNMO CAMs. 展开更多
关键词 LiNi_(0.5)Mn_(1.5)O_(4) Crystal facets Electrochemical degradation Chemical corrosion Surface energy
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Revealing interfacial charge redistribution of homologous Ru-RuS_(2) heterostructure toward robust hydrogen oxidation reaction
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作者 yi liu Lianrui Cheng +5 位作者 Shuqing Zhou Yuting Yang Chenggong Niu Tayirjan Taylor Isimjan Bao Wang Xiulin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期332-339,共8页
Precisely tailoring the surface electronic structures of electrocatalysts for optimal hydrogen binding energy and hydroxide binding energy is vital to improve the sluggish kinetics of hydrogen oxidation reac-tion(HOR)... Precisely tailoring the surface electronic structures of electrocatalysts for optimal hydrogen binding energy and hydroxide binding energy is vital to improve the sluggish kinetics of hydrogen oxidation reac-tion(HOR).Herein,we employ a partial desulfurization strategy to construct a homologous Ru-RuS_(2) heterostructure anchored on hollow mesoporous carbon nanospheres(Ru-RuS_(2)@C).The disparate work functions of the heterostructure contribute to the spontaneous formation of a unique built-in electric field,accelerating charge transfer and boosting conductivity of electrocatalyst.Consequently,Ru-RuS_(2)@C exhibits robust HOR electrocatalytic activity,achieving an exchange current density and mass activity as high as 3.56 mA cm^(-2) and 2.13 mAμg_(Ru)^(-1),respectively.exceeding those of state-of-the-art Pt/C and most contemporary Ru-based HOR electrocatalysts.Surprisingly,Ru-RuS_(2)@C can tolerate 1000 ppm of cO that lacks in Pt/C.Comprehensive analysis reveals that the directional electron transfer across Ru-RuS_(2) heterointerface induces local charge redistribution in interfacial region,which optimizes and balances the adsorption energies of H and OH species,as well as lowers the energy barrier for water formation,thereby promoting theHoR performance. 展开更多
关键词 HETEROSTRUCTURE Hollow spherical structure Hydrogen oxidation reaction Charge redistribution Density functional calculation
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Toward Establishing a Low-cost UAV Coordinated Carbon Observation Network(LUCCN):First Integrated Campaign in China
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作者 Dongxu YANG Tonghui ZHAO +11 位作者 Lu YAO Dong GUO Meng FAN Xiaoyu REN Mingge LI Kai WU Jing WANG Zhaonan CAI Sisi WANG Jiaxu GUO Liangfu CHEN yi liu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期1-7,共7页
In this study,we introduce our newly developed measurement-fed-perception self-adaption Low-cost UAV Coordinated Carbon Observation Network(LUCCN)prototype.The LUCCN primarily consists of two categories of instruments... In this study,we introduce our newly developed measurement-fed-perception self-adaption Low-cost UAV Coordinated Carbon Observation Network(LUCCN)prototype.The LUCCN primarily consists of two categories of instruments,including ground-based and UAV-based in-situ measurement.We use the GMP343,a low-cost non-dispersive infrared sensor,in both ground-based and UAV-based instruments.The first integrated measurement campaign took place in Shenzhen,China,4 May 2023.During the campaign,we found that LUCCN’s UAV component presented significant data-collecting advantages over its ground-based counterpart owing to the relatively high altitudes of the point emission sources,which was especially obvious at a gas power plant in Shenzhen.The emission flux was calculated by a crosssectional flux(CSF)method,the results of which differed from the Open-Data Inventory for Anthropogenic Carbon dioxide(ODIAC).The CSF result was slightly larger than others because of the low sampling rate of the whole emission cross section.The LUCCN system will be applied in future carbon monitoring campaigns to increase the spatiotemporal coverage of carbon emission information,especially in scenarios involving the detection of smaller-scale,rapidly varying sources and sinks. 展开更多
关键词 CO_(2) measurement networks power station carbon emission cross-sectional flux method
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Revealing precipitation behavior and mechanical response of wire-arc directed energy deposited Mg-Gd-Y-Zr alloy by tailoring aging procedures
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作者 Xinzhi Li Xuewei Fang +8 位作者 Zhiyan Zhang Shahid Ghafoor Ruikai Chen yi liu Kexin Tang Kai Li Minghua Ma Jiahao Shang Ke Huang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期176-200,共25页
Mg-Gd-Y-Zr alloy,as a typical magnesium rare-earth(Mg-RE)alloy,is gaining popularity in the advanced equipment manufacturing fields owing to its noticeable age-hardening properties and high specific strength.However,i... Mg-Gd-Y-Zr alloy,as a typical magnesium rare-earth(Mg-RE)alloy,is gaining popularity in the advanced equipment manufacturing fields owing to its noticeable age-hardening properties and high specific strength.However,it is extremely challenging to prepare wrought components with large dimensions and complex shapes because of the poor room-temperature processability of Mg-Gd-Y-Zr alloy.Herein,we report a wire-arc directed energy deposited(DED)Mg-10.45Gd-2.27Y-0.52Zr(wt.%,GW102K)alloy with high RE content presenting a prominent combination of strength and ductility,realized by tailored nanoprecipitates through an optimized heat treatment procedure.Specifically,the solution-treated sample exhibits excellent ductility with an elongation(EL)of(14.6±0.1)%,while the aging-treated sample at 200°C for 58 h achieves an ultra-high ultimate tensile strength(UTS)of(371±1.5)MPa.Besides,the aging-treated sample at 250°C for 16 h attains a good strength-ductility synergy with a UTS of(316±2.1)MPa and a EL of(8.5±0.1)%.Particularly,the evolution mechanisms of precipitation response induced by various aging parameters and deformation behavior caused by nanoprecipitates type were also systematically revealed.The excellent ductility resulted from coordinating localized strains facilitated by active slip activity.And the ultra-high strength should be ascribed to the dense nano-β'hampering dislocation motion.Additionally,the shearable nano-β1 contributed to the good strength-ductility synergy.This work thus offers insightful understanding into the nanoprecipitates manipulation and performance tailoring for the wire-arc DED preparation of large-sized Mg-Gd-Y-Zr components with complex geometries. 展开更多
关键词 wire-arc directed energy deposition Mg-Gd-Y-Zr alloy precipitation response prominent strength-ductilitycombination deformation mechanism
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Three-dimensionally oriented organization of hexagonal MIL-96 microplates toward superior film microstructure
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作者 Sixing Chen Xinmiao Jin +3 位作者 Yuyang Wu Taotao Ji Fei Wang yi liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期69-73,共5页
Preferential orientation control of metal—organic framework(MOF)films is advantageous for maximizing pore uniformity and minimizing grain-boundary defects.Nonetheless,the preparation of MOF films with both in-plane a... Preferential orientation control of metal—organic framework(MOF)films is advantageous for maximizing pore uniformity and minimizing grain-boundary defects.Nonetheless,the preparation of MOF films with both in-plane and out-of-plane orientations remains a grand challenge.In this study,we reported the preparation of three-dimensionally oriented MIL-96 layers through combining morphology control of MIL-96 seeds with addition of polyvinylpyrrolidone surfactants and arachidonic acids.The three-dimensionally oriented MIL-96 film was readily obtained through in-plane epitaxial growth.It is anticipated that the aforementioned protocol can be effective for obtaining diverse MOF films with a three-dimensionally oriented organization. 展开更多
关键词 Metaleorganic framework FILM Orientation Epitaxial growth Morphological control
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Photoinduced transposed Paternò-Büchi reaction for effective synthesis of high-performance jet fuel
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作者 Jinxiu Hu Xianlong liu +6 位作者 yi liu Kang Xue Chengxiang Shi Xiangwen Zhang Li Wang Ji-Jun Zou Lun Pan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期39-48,共10页
High-energy-density fuels are important for volume-limited aerospace vehicles,but the increase in fuel energy density always leads to poor cryogenic performance.Herein,we investigated the transposed Paternò-B... High-energy-density fuels are important for volume-limited aerospace vehicles,but the increase in fuel energy density always leads to poor cryogenic performance.Herein,we investigated the transposed Paternò-Büchi reaction of biomass cyclic ketone and cyclic alkene to synthesize a new kind of alkyl-substituted polycyclic hydrocarbon fuel with high energy density and good cryogenic performance.The triplet-energy-quenching results and phosphorescent emission spectra reveal the sensitization mechanism of the reaction,including photosensitizer excitation,triplettriplet energy transfer,cyclization,and relaxation,and the possible reaction path was revealed by the density functional theory(DFT)calculations.The reaction conditions of photosensitizer type and addition,molar ratio of substrates,reaction temperature,and incident light intensity were optimized,with the target product yield achieving 65.5%.Moreover,the reaction dynamics of the reaction rate versus the light intensity are established.After the hydrogenation-deoxygenation reaction,three fuels with a high density of 0.864-0.938 g·ml^(-1) and a low freezing point of<-55℃ are obtained.This work provides a benign and effective approach to synthesize high-performance fuels. 展开更多
关键词 High-energy-density fuel Transposed Patern-oeBüchi reaction Kinetics BIOENERGY PHOTOCHEMISTRY
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NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation
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作者 Zhihao Lin Changzhou ying +6 位作者 Xiaoli Si Naijia Xue yi liu Ran Zheng ying Chen Jiali Pu Baorong Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第7期2038-2052,共15页
Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra compacta.Ferroptosis,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidati... Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra compacta.Ferroptosis,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic neurons.However,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely elucidated.NADPH oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains unknown.The aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what mechanism.We found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease model.NADPH oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic neurons.Moreover,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model animals.Mechanistically,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic neurons.Furthermore,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced neuroinflammation.These findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease. 展开更多
关键词 dopaminergic neuron ferroptosis NADPH oxidase 4(NOX4) NEUROINFLAMMATION Parkinson's disease
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circPVT1 promotes silica-induced epithelial-mesenchymal transition by modulating the miR-497-5p/TCF3 axis
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作者 Siyun Zhou Yan Li +5 位作者 Wenqing Sun Dongyu Ma yi liu Demin Cheng Guanru Li Chunhui Ni 《Journal of Biomedical Research》 CAS CSCD 2024年第2期163-174,I0011-I0015,共17页
Epithelial-mesenchymal transition(EMT)is a vital pathological feature of silica-induced pulmonary fibrosis.However,whether circRNA is involved in the process remains unclear.The present study aimed to investigate the ... Epithelial-mesenchymal transition(EMT)is a vital pathological feature of silica-induced pulmonary fibrosis.However,whether circRNA is involved in the process remains unclear.The present study aimed to investigate the role of circPVT1 in the silica-induced EMT and the underlying mechanisms.We found that an elevated expression of circPVT1 promoted EMT and enhanced the migratory capacity of silica-treated epithelial cells.The isolation of cytoplasmic and nuclear separation assay showed that circPVT1 was predominantly expressed in the cytoplasm.RNA immunoprecipitation assay and RNA pull-down experiment indicated that cytoplasmic-localized circPVT1 was capable of binding to miR-497-5p.Furthermore,we found that miR-497-5p attenuated the silica-induced EMT process by targeting transcription factor 3(TCF3),an E-cadherin transcriptional repressor,in the silica-treated epithelial cells.Collectively,these results reveal a novel role of the circPVT1/miR-497-5p/TCF3 axis in the silica-induced EMT process in lung epithelial cells.Once validated,this finding may provide a potential theoretical basis for the development of interventions and treatments for pulmonary fibrosis. 展开更多
关键词 SILICOSIS epithelial-mesenchymal transition circPVT1 miR-497-5p TCF3
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Part-Whole Relational Few-Shot 3D Point Cloud Semantic Segmentation
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作者 Shoukun Xu Lujun Zhang +2 位作者 Guangqi Jiang yining Hua yi liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3021-3039,共19页
This paper focuses on the task of few-shot 3D point cloud semantic segmentation.Despite some progress,this task still encounters many issues due to the insufficient samples given,e.g.,incomplete object segmentation an... This paper focuses on the task of few-shot 3D point cloud semantic segmentation.Despite some progress,this task still encounters many issues due to the insufficient samples given,e.g.,incomplete object segmentation and inaccurate semantic discrimination.To tackle these issues,we first leverage part-whole relationships into the task of 3D point cloud semantic segmentation to capture semantic integrity,which is empowered by the dynamic capsule routing with the module of 3D Capsule Networks(CapsNets)in the embedding network.Concretely,the dynamic routing amalgamates geometric information of the 3D point cloud data to construct higher-level feature representations,which capture the relationships between object parts and their wholes.Secondly,we designed a multi-prototype enhancement module to enhance the prototype discriminability.Specifically,the single-prototype enhancement mechanism is expanded to the multi-prototype enhancement version for capturing rich semantics.Besides,the shot-correlation within the category is calculated via the interaction of different samples to enhance the intra-category similarity.Ablation studies prove that the involved part-whole relations and proposed multi-prototype enhancement module help to achieve complete object segmentation and improve semantic discrimination.Moreover,under the integration of these two modules,quantitative and qualitative experiments on two public benchmarks,including S3DIS and ScanNet,indicate the superior performance of the proposed framework on the task of 3D point cloud semantic segmentation,compared to some state-of-the-art methods. 展开更多
关键词 Few-shot point cloud semantic segmentation CapsNets
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Superconductivity in kagome metal ThRu_(3)Si_(2)
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作者 刘艺 厉静 +12 位作者 杨武璋 卢佳依 曹博雅 李华旬 柴万力 武思祺 李佰卓 孙云蕾 焦文鹤 王操 许晓峰 任之 曹光旱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期36-41,共6页
We report the physical properties of ThRu_(3)Si_(2)featured with distorted Ru kagome lattice.The combined experiments of resistivity,magnetization and specific heat reveal bulk superconductivity with T_(c)=3.8 K.The s... We report the physical properties of ThRu_(3)Si_(2)featured with distorted Ru kagome lattice.The combined experiments of resistivity,magnetization and specific heat reveal bulk superconductivity with T_(c)=3.8 K.The specific heat jump and calculated electron–phonon coupling indicate a moderate coupled BCS superconductor.In comparison with LaRu_(3)Si_(2),the calculated electronic structure in ThRu_(3)Si_(2)shows an electron-doping effect with electron filling lifted from 100 meV below flat bands to 300 meV above it.This explains the lower superconducting transition temperature and weaker electron correlations observed in ThRu_(3)Si_(2).Our work suggests the Tc and electronic correlations in the kagome superconductor could have an intimate connection with the flat bands. 展开更多
关键词 SUPERCONDUCTIVITY kagome lattice flat band
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TransTM:A device-free method based on time-streaming multiscale transformer for human activity recognition
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作者 yi liu Weiqing Huang +4 位作者 Shang Jiang Bobai Zhao Shuai Wang Siye Wang Yanfang Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期619-628,共10页
RFID-based human activity recognition(HAR)attracts attention due to its convenience,noninvasiveness,and privacy protection.Existing RFID-based HAR methods use modeling,CNN,or LSTM to extract features effectively.Still... RFID-based human activity recognition(HAR)attracts attention due to its convenience,noninvasiveness,and privacy protection.Existing RFID-based HAR methods use modeling,CNN,or LSTM to extract features effectively.Still,they have shortcomings:1)requiring complex hand-crafted data cleaning processes and 2)only addressing single-person activity recognition based on specific RF signals.To solve these problems,this paper proposes a novel device-free method based on Time-streaming Multiscale Transformer called TransTM.This model leverages the Transformer's powerful data fitting capabilities to take raw RFID RSSI data as input without pre-processing.Concretely,we propose a multiscale convolutional hybrid Transformer to capture behavioral features that recognizes singlehuman activities and human-to-human interactions.Compared with existing CNN-and LSTM-based methods,the Transformer-based method has more data fitting power,generalization,and scalability.Furthermore,using RF signals,our method achieves an excellent classification effect on human behaviorbased classification tasks.Experimental results on the actual RFID datasets show that this model achieves a high average recognition accuracy(99.1%).The dataset we collected for detecting RFID-based indoor human activities will be published. 展开更多
关键词 Human activity recognition RFID TRANSFORMER
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Plant Chemical Defenses against Insect Herbivores—Using theWild Tobacco as a Model
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作者 Guangwei Sun Xuanhao Zhang +4 位作者 yi liu Liguang Chai Daisong liu Zhenguo Chen Shiyou Lü 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期641-659,共19页
The Nicotiana genus, commonly known as tobacco, holds significant importance as a crucial economic crop. Confrontedwith an abundance of herbivorous insects that pose a substantial threat to yield, tobacco has develope... The Nicotiana genus, commonly known as tobacco, holds significant importance as a crucial economic crop. Confrontedwith an abundance of herbivorous insects that pose a substantial threat to yield, tobacco has developed adiverse and sophisticated array of mechanisms, establishing itself as a model of plant ecological defense. Thisreview provides a concise overview of the current understanding of tobacco’s defense strategies against herbivores.Direct defenses, exemplified by its well-known tactic of secreting the alkaloid nicotine, serve as a potent toxinagainst a broad spectrum of herbivorous pests. Moreover, in response to herbivore attacks, tobacco enhancesthe discharge of volatile compounds, harnessing an indirect strategy that attracts the predators of the herbivores.The delicate balance between defense and growth leads to the initiation of most defense strategies only after aherbivore attack. Among plant hormones, notably jasmonic acid (JA), play central roles in coordinating thesedefense processes. JA signaling interacts with other plant hormone signaling pathways to facilitate the extensivetranscriptional and metabolic adjustments in plants following herbivore assault. By shedding light on these ecologicaldefense strategies, this review emphasizes not only tobacco’s remarkable adaptability in its natural habitatbut also offers insights beneficial for enhancing the resilience of current crops. 展开更多
关键词 TOBACCO HERBIVORE chemical defense jasmonic acid REGULATION
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