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Effects of β-Glucan Supplementation on Repairing of Phenol-Induced Vaginal Mucosal Epithelium Damage in Rats
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作者 Song Fei Weidong Wu +2 位作者 Ying Wang dan li Bo Jin 《Open Journal of Obstetrics and Gynecology》 2024年第4期535-546,共12页
Objective: To investigate the effects of different concentrations of β-glucan on the repair of damaged vaginal mucosa, the expression of vascular endothelial growth factor (VEGF), and the inflammatory factor-6 (IL-6)... Objective: To investigate the effects of different concentrations of β-glucan on the repair of damaged vaginal mucosa, the expression of vascular endothelial growth factor (VEGF), and the inflammatory factor-6 (IL-6) in vaginal tissues. Methods: Thirty-six adult female specific pathogen free (SPF)-grade Wistar rats were randomly divided into 3 phase groups with 12 rats each. Vaginal inflammation rat models were established by injecting phenol gel into the vagina of each rat at a dose of 0.1 ml/100g body weight. After modeling, rats were divided into 4 groups based on different concentrations of the test agent. The control group was injected with 0.5 ml of saline, experimental group A was injected with 0.375 ml saline 0.125 ml β-glucan, experimental group B was injected with 0.25 ml saline 0.25 ml β-glucan, and experimental group C was injected with 0.50 ml β-glucan. The injection sites were selected at the 3 o’clock and 9 o’clock positions of the vagina. Rats were sacrificed at 7-, 14-, and 28-days post-injection, and tissue samples were collected from the injection sites and prepared for histological analysis. New blood vessels and fibroblast numbers in the tissues were observed after Hematoxylin-eosin (HE) staining. The expression levels of VEGF and IL-6 in the tissues were measured using quantificational reverse transcription polymerase chain reaction (qRT-PCR). Results: Histological examination of vaginal tissue specimens at 7-, 14-, and 28-days post-injection showed that on day 7, there were no significant changes in the experimental groups compared to the control group. However, on days 14 and 28, the experimental groups showed more new blood vessels, macrophages, and fibroblasts with increased activity compared to the control group. The expression levels of VEGF in vaginal tissues were elevated on days 14 and 28 in the experimental groups. The comparison of IL-6 levels in vaginal tissues on day 28 showed that serum IL-6 levels returned to normal, and there was no statistically significant difference between the experimental and control groups. Conclusion: In the 3 experimental phases, the increase in VEGF levels in vaginal tissues on day 14 post-injection was more pronounced with higher concentrations of β-glucan, and IL-6 levels returned to normal on day 28. β-Glucan can enhance VEGF levels in damaged vaginal tissues, promote the repair of damaged vaginal tissues, and higher concentrations of β-glucan have a better effect. 展开更多
关键词 Β-GLUCAN Vaginal Mucosa Damage Repair
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Comparison between ozonesonde measurements and satellite retrievals over Beijing,China 被引量:2
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作者 Jinqiang Zhang Yuejian Xuan +5 位作者 Jianchun Bian Holger Vomel Yunshu Zeng Zhixuan Bai dan li Hongbin Chen 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期14-20,共7页
从2013年开始,作者团队使用自主研发电化学原理臭氧探空仪在华北平原北京地区进行每周一次观测.本研究首次使用2013-2019年期间北京地区臭氧探空数据评估Aqua卫星搭载大气红外探测仪(AIRS)和Aura卫星搭载微波临边探测器(MLS)反演垂直臭... 从2013年开始,作者团队使用自主研发电化学原理臭氧探空仪在华北平原北京地区进行每周一次观测.本研究首次使用2013-2019年期间北京地区臭氧探空数据评估Aqua卫星搭载大气红外探测仪(AIRS)和Aura卫星搭载微波临边探测器(MLS)反演垂直臭氧廓线,并对比臭氧探空,AIRS和Aura卫星搭载臭氧监测仪(OMI)臭氧柱总量结果.尽管臭氧探空与卫星反演垂直臭氧廓线在局部高度处差异较大,但整体来说两者较为接近(相对偏差大多<10%).臭氧探空,AIRS和OMI三种仪器测量臭氧柱总量的年变化特征较为一致,其年均臭氧柱总量分别为351.8±18.4 DU,348.8±19.5 DU和336.9±14.2 DU.后续对国内多站点观测数据分析将有助于进一步理解臭氧探空与卫星反演臭氧资料在不同区域的一致性. 展开更多
关键词 臭氧探空 卫星反演 垂直臭氧廓线 臭氧柱总量 华北平原
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Efficacy of exercise rehabilitation for managing patients with Alzheimer's disease 被引量:1
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作者 dan li Jinning Jia +3 位作者 Haibo Zeng Xiaoyan Zhong Hui Chen Chenju Yi 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2175-2188,共14页
Alzheimer's disease(AD) is a progressive and degenerative neurological disease characterized by the deterioration of cognitive functions. While a definitive cure and optimal medication to impede disease progressio... Alzheimer's disease(AD) is a progressive and degenerative neurological disease characterized by the deterioration of cognitive functions. While a definitive cure and optimal medication to impede disease progression are currently unavailable, a plethora of studies have highlighted the potential advantages of exercise rehabilitation for managing this condition. Those studies show that exercise rehabilitation can enhance cognitive function and improve the quality of life for individuals affected by AD. Therefore, exercise rehabilitation has been regarded as one of the most important strategies for managing patients with AD. Herein, we provide a comprehensive analysis of the currently available findings on exercise rehabilitation in patients with AD, with a focus on the exercise types which have shown efficacy when implemented alone or combined with other treatment methods, as well as the potential mechanisms underlying these positive effects. Specifically, we explain how exercise may improve the brain microenvironment and neuronal plasticity. In conclusion, exercise is a cost-effective intervention to enhance cognitive performance and improve quality of life in patients with mild to moderate cognitive dysfunction. Therefore, it can potentially become both a physical activity and a tailored intervention. This review may aid the development of more effective and individualized treatment strategies to address the challenges imposed by this debilitating disease, especially in low-and middle-income countries. 展开更多
关键词 Alzheimer's disease cerebrovascular function cognitive function epigenetic regulation EXERCISE hippocampal neurogenesis MITOCHONDRIA NEUROINFLAMMATION neuronal plasticity
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Delving into the dissimilarities in electrochemical performance and underlying mechanisms for sodium and potassium ion storage in N-doped carbon-encapsulated metallic Cu_(2)Se nanocubes
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作者 Xinyu Wang Yanan Xu +4 位作者 Xiaofeng liu Lei Tan Huaiqiang Gu Xin Du dan li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期336-347,I0008,共13页
The large volumetric variations experienced by metal selenides within conversion reaction result in inferior rate capability and cycling stability,ultimately hindering the achievement of superior electrochemical perfo... The large volumetric variations experienced by metal selenides within conversion reaction result in inferior rate capability and cycling stability,ultimately hindering the achievement of superior electrochemical performance.Herein,metallic Cu_(2)Se encapsulated with N-doped carbon(Cu_(2)Se@NC)was prepared using Cu_(2)O nanocubes as templates through a combination of dopamine polymerization and hightemperature selenization.The unique nanocubic structure and uniform N-doped carbon coating could shorten the ion transport distance,accelerate electron/charge diffusion,and suppress volume variation,ultimately ensuring Cu_(2)Se@NC with excellent electrochemical performance in sodium ion batteries(SIBs)and potassium ion batteries(PIBs).The composite exhibited excellent rate performance(187.7 mA h g^(-1)at 50 A g^(-1)in SIBs and 179.4 mA h g^(-1)at 5 A g^(-1)in PIBs)and cyclic stability(246,8 mA h g^(-1)at 10 A g^(-1)in SIBs over 2500 cycles).The reaction mechanism of intercalation combined with conversion in both SIBs and PIBs was disclosed by in situ X-ray diffraction(XRD)and ex situ transmission electron microscope(TEM).In particular,the final products in PIBs of K_(2)Se and K_(2)Se_(3)species were determined after discharging,which is different from that in SIBs with the final species of Na_(2)Se.The density functional theory calculation showed that carbon induces strong coupling and charge interactions with Cu_(2)Se,leading to the introduction of built-in electric field on heterojunction to improve electron mobility.Significantly,the theoretical calculations discovered that the underlying cause for the relatively superior rate capability in SIBs to that in PIBs is the agile Na~+diffusion with low energy barrier and moderate adsorption energy.These findings offer theoretical support for in-depth understanding of the performance differences of Cu-based materials in different ion storage systems. 展开更多
关键词 Cu_(2)Se nanocubes DFT calculations Ion storage mechanism Potassium ion batteries Sodium ion batteries
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Effect of lattice distortion on spin admixture and quantum transport in organic devices with spin–orbit coupling
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作者 王莹 李丹 +6 位作者 孙新英 张惠晴 马晗 李慧欣 任俊峰 王传奎 胡贵超 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期519-527,共9页
With an extended Su–Schrieffer–Heeger model and Green's function method, the spin–orbit coupling(SOC) effects on spin admixture of electronic states and quantum transport in organic devices are investigated. Th... With an extended Su–Schrieffer–Heeger model and Green's function method, the spin–orbit coupling(SOC) effects on spin admixture of electronic states and quantum transport in organic devices are investigated. The role of lattice distortion induced by the strong electron–lattice interaction in organics is clarified in contrast with a uniform chain. The results demonstrate an enhanced SOC effect on the spin admixture of frontier eigenstates by the lattice distortion at a larger SOC,which is explained by the perturbation theory. The quantum transport under the SOC is calculated for both nonmagnetic and ferromagnetic electrodes. A more notable SOC effect on total transmission and current is observed for ferromagnetic electrodes, where spin filtering induced by spin-flipped transmission and suppression of magnetoresistance are obtained.Unlike the spin admixture, a stronger SOC effect on transmission exists for the uniform chain rather than the organic lattices with distortion. The reason is attributed to the modified spin-polarized conducting states in the electrodes by lattice configuration, and hence the spin-flip transmission, instead of the spin admixture of eigenstates. This work is helpful to understand the SOC effect in organic spin valves in the presence of lattice distortion. 展开更多
关键词 organic spintronics spin–orbit coupling spin admixture quantum transport
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Application of Optical Hydrogels in Environmental Sensing
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作者 Shuo Yang Shruti Sarkar +2 位作者 Xing Xie dan li Jianmin Chen 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期311-336,共26页
The ever-increasing complexity of environmental pollutants urgently warrants the development of new detection technologies.Sensors based on the optical properties of hydrogels enabling fast and easy in situ detection ... The ever-increasing complexity of environmental pollutants urgently warrants the development of new detection technologies.Sensors based on the optical properties of hydrogels enabling fast and easy in situ detection are attracting increasing attention.In this paper,the data from 138 papers about different optical hydrogels(OHs)are extracted for statistical analysis.The detection performance and potential of various types of OHs in different environmental pollutant detection scenarios were evaluated and compared to those obtained using the standard detection method.Based on this analysis,the target recognition and sensing mechanisms of two main types of OHs are reviewed and discussed:photonic crystal hydrogels(PCHs)and fluorescent hydrogels(FHs).For PCHs,the environmental stimulus response,target receptors,inverse opal structures,and molecular imprinting techniques related to PCHs are reviewed and summarized.Furthermore,the different types of fluorophores(i.e.,compound probes,biomacromolecules,quantum dots,and luminescent microbes)of FHs are discussed.Finally,the potential academic research directions to address the challenges of applying and developing OHs in environmental sensing are proposed,including the fusion of various OHs,introduction of the latest technologies in various fields to the construction of OHs,and development of multifunctional sensor arrays. 展开更多
关键词 environmental sensors fluorescent hydrogel optical hydrogel photonic crystal hydrogel pollution detection
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Primary coexisting adenocarcinoma of the colon and neuroendocrine tumor of the duodenum: A case report and review of the literature
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作者 Song Fei Wei-Dong Wu +3 位作者 Han-Shuo Zhang Shao-Jie liu dan li Bo Jin 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2724-2734,共11页
BACKGROUND Neuroendocrine tumors(NETs)arise from the body’s diffuse endocrine system.Coexisting primary adenocarcinoma of the colon and NETs of the duodenum(D-NETs)is a rare occurrence in clinical practice.The classi... BACKGROUND Neuroendocrine tumors(NETs)arise from the body’s diffuse endocrine system.Coexisting primary adenocarcinoma of the colon and NETs of the duodenum(D-NETs)is a rare occurrence in clinical practice.The classification and treatment criteria for D-NETs combined with a second primary cancer have not yet been determined.CASE SUMMARY We report the details of a case involving female patient with coexisting primary adenocarcinoma of the colon and a D-NET diagnosed by imaging and surgical specimens.The tumors were treated by surgery and four courses of chemothe-rapy.The patient achieved a favorable clinical prognosis.CONCLUSION Coexisting primary adenocarcinoma of the colon and D-NET were diagnosed by imaging,laboratory indicators,and surgical specimens.Surgical resection com-bined with chemotherapy was a safe,clinically effective,and cost-effective treat-ment. 展开更多
关键词 Neuroendocrine tumor of the duodenum Multiple primary tumors Colorectal cancer Endoscopic resection Case report
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High levels of genetic diversity and an absence of genetic structure among breeding populations of the endangered Rufous-backed Bunting in Inner Mongolia,China:implications for conservation 被引量:1
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作者 Shi li dan li +3 位作者 lishi Zhang Weiping Shang Bo Qin Yunlei Jiang 《Avian Research》 CSCD 2021年第1期52-62,共11页
Background:The Rufous-backed Bunting,Emberiza jankowskii,is an endangered species that is primarily distributed in Inner Mongolia,China.The main threats to the continued persistence of this species are habitat loss an... Background:The Rufous-backed Bunting,Emberiza jankowskii,is an endangered species that is primarily distributed in Inner Mongolia,China.The main threats to the continued persistence of this species are habitat loss and degradation.However,the impact of population loss on genetic diversity remains unclear.To support future conservation and management efforts,we assessed the genetic diversity and population structure of E.jankowskii using mitochondrial DNA and microsatellites.Methods:Blood samples were collected from 7-8-day-old nestlings in Inner Mongolia,China between May and August of 2012 and 2013.Mitochondrial DNA sequences and microsatellite markers were used to assess the genetic diversity,genetic structure and inbreeding of E.jankowskii.The results of genetic diversity and inbreeding were compared to other avian species.Results:We found an unexpectedly high level of genetic diversity in terms of mitochondrial DNA and microsatellite compared to other avian species.However,there were high levels of gene flow and minimal genetic structuring,among the fragmented breeding populations of E.jankowskii in Inner Mongolia.These findings suggest that E.jankowskii in Inner Mongolia is a metapopulation.Despite the high genetic diversity of E.jankowskii,local populations in each small patch remain at risk of extinction due to habitat loss.In addition,the E.jankowskii population has a high risk of inbreeding.Conclusions:To minimize further loss of genetic diversity of this endangered species,we suggest that the E.jankowskii in Inner Mongolia should be considered as a protected species for management purposes.Conservation efforts should concentrate on E.jankowskii habitat management.This may be most effectively achieved by protecting the current breeding habitats and prohibiting over-grazing. 展开更多
关键词 CONSERVATION Emberiza jankowskii Genetic diversity Genetic structure Habitat fragmentation
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Enhancing the compatibility of the amyloid-dye hybrid nanostructure for improved photo-biocatalysis
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作者 Zhen Dong Yanying Wang +2 位作者 Qin Yang dan li Peng Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期430-437,I0012,共9页
Artificial photosynthesis is significant for renewable energy generation,sustainable development,and environmental protection.Dye-protein hybrids are promising for developing photosynthesis mimics(e.g.,photo-biocataly... Artificial photosynthesis is significant for renewable energy generation,sustainable development,and environmental protection.Dye-protein hybrids are promising for developing photosynthesis mimics(e.g.,photo-biocatalysis),but their performances are far lower than the plant photosystems,partially because of the incompatibility between dye and the protein matrix that limits excited state electron transfer of the included dyes.Here,using ThT-insulin amyloid assembly as a model system,we proposed that increasing the dye-protein compatibility could lead to the improved photo-biocatalytic performance.A ThT derivative,ThTPD,was designed with the same electron acceptor but extended π-conjugated donor structure.When integrated into the insulin amyloid,the extended π-conjugated donor structure allowed increased binding affinity and energy with the amyloid matrix,thus better electron transport to the mediator to drive the photocatalytic reaction.Meanwhile,compared with ThT, ThTPD exhibited improved light absorption and longer excited state lifetime.The photo-biocatalytic performance of ThTPD-insulin amyloid was greatly improved as compared with that of ThT in reduced nicotinamide adenine dinucleotide(NADH) regeneration.When integrating with NADH-dependent L-glutamate reductase,the efficiency of the ThTPD-insulin amyloid hybrid was 2.8-fold higher than that of ThT in glutamate generation,showing promising feature in biocatalytic solar-to-chemical conversion. 展开更多
关键词 Photo-biocatalysis Dye-protein assembly Insulin amyloid THT Compatibility
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Dielectric polarization in MgFe_(2)O_(4) coating and bulk doping to enhance high-voltage cycling stability of Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2) cathode material
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作者 Xiaoqian Xu Yizhen Huang +7 位作者 dan li Qichang Pan Sijiang Hu Yahao li Hongqiang Wang Youguo Huang Fenghua Zheng Qingyu li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期200-211,I0007,共13页
Charging P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)to 4.5 V for higher capacity is enticing.However,it leads to severe capacity fading,ascribing to the lattice oxygen evolution and the P2-O2 phase transformation.Here,the Mg Fe_... Charging P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)to 4.5 V for higher capacity is enticing.However,it leads to severe capacity fading,ascribing to the lattice oxygen evolution and the P2-O2 phase transformation.Here,the Mg Fe_(2)O_(4) coating and Mg,Fe co-doping were constructed simultaneously by Mg,Fe surface treatment to suppress lattice oxygen evolution and P2-O2 phase transformation of P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)at deep charging.Through ex-situ X-ray diffraction(XRD)tests,we found that the Mg,Fe bulk co-doping could reduce the repulsion between transition metals and Na+/vacancies ordering,thus inhibiting the P2-O2 phase transition and significantly reducing the irreversible volume change of the material.Meanwhile,the internal electric field formed by the dielectric polarization of Mg Fe_(2)O_(4) effectively inhibits the outward migration of oxidized O^(a-)(a<2),thereby suppressing the lattice oxygen evolution at deep charging,confirmed by in situ Raman and ex situ XPS techniques.P2-Na NM@MF-3 shows enhanced high-voltage cycling performance with capacity retentions of 84.8% and 81.3%at 0.1 and 1 C after cycles.This work sheds light on regulating the surface chemistry for Na-layered oxide materials to enhance the high-voltage performance of Na-ion batteries. 展开更多
关键词 P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2) MgFe_(2)O_(4) Bulk doping Lattice oxygen evolution P2-O2 phase transformation
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Single-cell RNA-sequencing and subcellular spatial transcriptomics facilitate the translation of liver microphysiological systems for regulatory application
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作者 dan li Zhou Fang +5 位作者 Qiang Shi Nicholas Zhang Binsheng Gong Weida Tong Ahmet F.Coskun Joshua Xu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第7期691-693,共3页
Reducing the use of animal models in drug development and safety assessment has long been supported by the U.S.Food and Drug Administration(FDA).The report by Royal Society for the Prevention of Cruelty to Animals ind... Reducing the use of animal models in drug development and safety assessment has long been supported by the U.S.Food and Drug Administration(FDA).The report by Royal Society for the Prevention of Cruelty to Animals indicates that in 2020,experiments involved the use of over 100 million animals,with the United States leading the list by utilizing 20 million animals.Beyond ethical considerations associated with animal testing and the costs in terms of time and money,animal models are not always effective in predicting human reactions to drug exposure.While animal testing has been the traditional method for assessing the safety and efficacy of drugs. 展开更多
关键词 MONEY utilizing testing
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Effects and mechanism of miRNA-24 on the proliferation,migration and tube formation of vascular endothelial cells
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作者 Xiaojing Tao Feng Shen +5 位作者 Peng Yang Xuelan Luo dan li Yuanyuan Yan Yongxiong Zhong Hesheng Ou 《广西医科大学学报》 CAS 2018年第7期901-906,共6页
Objective:To investigate the effect and mechanism of miRNA-24 on the proliferation,migration and tube formation of vascular endothelial cells.Methods:Human umbilical vein endothelial cells(HUVECs)were assigned into co... Objective:To investigate the effect and mechanism of miRNA-24 on the proliferation,migration and tube formation of vascular endothelial cells.Methods:Human umbilical vein endothelial cells(HUVECs)were assigned into control,microRNA(miR)-24 overexpression and anti-miR-24 groups.The proliferation and migration abilities of HUVECs were detected by methyl thiazolyl tetrazolium(MTT)assay and scratch wound healing assay,respectively.The ability of HUVECs to form tubular structures was evaluated by a tube formation assay.The mRNA and protein expressions of vascular endothelial growth factor(VEGF)and transcription factor Sp1 were determined by RT-PCR,immunocytochemistry and western blotting,respectively.Results:The miR-24 overexpression group exhibited decreased cell proliferation and migration,and expressions of VEGF and Sp1 compared with the control group(P <0.01).No tube-like network structure was formed in the miR-24 overexpression group.However,inhibition of miR-24 in HUVECs markedly increased cell proliferation and migration,enhanced tube formation and expressions of VEGF and Sp1(P<0.05 or P<0.01).Conclusion:MiR-24 suppressed the proliferation,migration and tube formation of HUVECs,and the mechanism might be related to the down-regulation of VEGF expression.Sp1 might participate in this regulation process. 展开更多
关键词 miRNA-24 vascular endothelial growth factor SP1 endothelial cells tube formation
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双金属浸出诱导催化剂重构用于高活性和高稳定性电化学水氧化
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作者 许文涛 莫栩妍 +10 位作者 周洋 翁祖贤 莫坤玲 吴炎桦 蒋欣霖 李丹 蓝汤淇 文欢 郑伏琴 樊友军 陈卫 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第8期40-42,共3页
析氧反应(OER)催化剂在催化反应过程中不可避免地会发生表面重构,这一过程使得设计、构筑高性能和高稳定性的OER电催化剂充满挑战。在此,我们采用双金属浸出诱导表面重构的策略,构建了高活性和高稳定性的水氧化电催化剂。在该策略中,通... 析氧反应(OER)催化剂在催化反应过程中不可避免地会发生表面重构,这一过程使得设计、构筑高性能和高稳定性的OER电催化剂充满挑战。在此,我们采用双金属浸出诱导表面重构的策略,构建了高活性和高稳定性的水氧化电催化剂。在该策略中,通过水热、离子交换和后续的退火工艺处理,将由α-CoMoO_(4)、K_(2)Co_(2)(MoO_(4))_(3)、Co_(3)O_(4)和CoFe_(2)O_(4)四种氧化物晶相组成的材料阵列转换为OER预催化剂。原位电化学拉曼光谱和非原位X射线衍射(XRD)分析表明,其中的不稳定成分K_(2)Co_(2)(MoO_(4))_(3)的快速溶解引发了Mo和K的适度浸出,从而在低电压下加速了表面富集的α-Co(OH)_(2)向CoOOH活性相的转化。此外,CoFe_(2)O_(4)相耦合重构产生新相CoO与无定形层CoOOH,从而形成了CoFe_(2)O_(4)@CoO@CoOOH紧密的多相结构,起到了“纳米栅栏”的作用,可有效防止催化剂的过度重构,从而赋予重构后的催化剂优异的催化活性和稳定性。本工作为设计高电流密度下具有优异活性和稳定性的OER催化剂提供了新的思路。 展开更多
关键词 析氧反应 表面重构 离子浸出 水分解 电催化 催化剂
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Interface Engineering of Titanium Nitride Nanotube Composites for Excellent Microwave Absorption at Elevated Temperature 被引量:3
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作者 Cuiping li dan li +4 位作者 Shuai Zhang Long Ma Lei Zhang Jingwei Zhang Chunhong Gong 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期147-160,共14页
Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently... Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently,the development of high-performance EMWA materials with good impedance matching and strong loss ability in wide temperature spectrum has emerged as a top priority.Herein,due to the high melting point,good electrical conductivity,excellent environmental stability,EM coupling effect,and abundant interfaces of titanium nitride(TiN)nanotubes,they were designed based on the controlling kinetic diffusion procedure and Ostwald ripening process.Benefiting from boosted heterogeneous interfaces between TiN nanotubes and polydimethylsiloxane(PDMS),enhanced polarization loss relaxations were created,which could not only improve the depletion efficiency of EMWA,but also contribute to the optimized impedance matching at elevated temperature.Therefore,the TiN nanotubes/PDMS composite showed excellent EMWA performances at varied temperature(298-573 K),while achieved an effective absorption bandwidth(EAB)value of 3.23 GHz and a minimum reflection loss(RLmin)value of−44.15 dB at 423 K.This study not only clarifies the relationship between dielectric loss capacity(conduction loss and polarization loss)and temperature,but also breaks new ground for EM absorbers in wide temperature spectrum based on interface engineering. 展开更多
关键词 TiN nanotubes Interface engineering Polarization loss Impedance matching Electromagnetic wave absorption performance
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加密地面站观测资料同化对中国区域数值模拟的影响
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作者 贾佳 丹利 +1 位作者 王立志 詹思玙 《气候与环境研究》 CSCD 北大核心 2024年第5期605-614,共10页
基于全球数值预报模式,利用格点同化系统(Grid point Statistical Interpolation system,GSI)将中国区域2170个地面自动气象站进行数据同化,建立了中国区域新的模式初始场,对比了中国区域气温、气压和风速3种气象要素的背景场和初始场... 基于全球数值预报模式,利用格点同化系统(Grid point Statistical Interpolation system,GSI)将中国区域2170个地面自动气象站进行数据同化,建立了中国区域新的模式初始场,对比了中国区域气温、气压和风速3种气象要素的背景场和初始场特征以及同化后预报效果与欧洲中心再分析数据差异。结果表明:尽管仅仅同化了中国区域的观测数据,但同化后的模式平均偏差、均方根偏差和代价函数均显著降低,表明同化地面观测站资料能有效地降低模式背景场中的气温、气压和风速等基本物理量的误差,使模式的初始分析场和实际观测场更为一致;而在中国区域,3种气象要素的预报中气压的预报效果最好,7个区域气压的相关系数均达0.94以上,且同化后7个区域的相关系数均有提升,东北、华东等区域相关系数高达0.99;各区域气温的相关系数在同化后也略有提高,均方根误差在同化后有所降低,其中华南地区降幅最大,降低了2.3%。相对气压和气温而言,经向风和纬向风同化后改进不大,与再分析数据的相关系数偏小,同时均方根误差较大。其中,华东、西南和华中区域的经向风相关系数低于0.5,东北地区的经向风和纬向风的均方根误差均大于5 m s^(-1)。 展开更多
关键词 数值预报 资料同化 区域对比
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Water-soluble organic matter with various polarities in PM_(2.5) over Xi'an,China:Abundance,functional groups,and light absorption 被引量:1
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作者 Xueting Yang Shasha Huang +7 位作者 dan li Hongmei Xu Yaling Zeng liu Yang Diwei Wang Ningning Zhang Junji Cao Zhenxing Shen 《Particuology》 SCIE EI CAS CSCD 2024年第1期281-289,共9页
Humic-like substances(HULIS)are a major component of brown carbon and consequently play a major role in climate change.In this study,70 PM_(2.5) samples were collected from Xi'an in winter 2019 and summer 2020.Neu... Humic-like substances(HULIS)are a major component of brown carbon and consequently play a major role in climate change.In this study,70 PM_(2.5) samples were collected from Xi'an in winter 2019 and summer 2020.Neutral HULIS(HULIS-n),acidic HULIS(HULIS-a),and high-polarity water-soluble organic compounds(HP-WSOC)were analyzed to determine their carbon concentrations and measure their ultraviolet-visible absorption and infrared spectra.Of the three components,HULIS-n had the highest carbon content in both winter(3.29±1.45μg m^(-3))and in summer(1.38±1.10μg m^(-3)).The semi-quantitative results for the functional groups revealed that HP-WSOC was rich in carboxylic acids and had high aromaticity in winter,whereas HULIS-n was rich in carboxylic acids in summer.Moreover,HULJS-a was richer in nitrate esters and saturated aliphatic hydrocarbons in summer than in winter.The results for specific ultraviolet absorbance(SUVA)and E_(250)/E_(365) revealed that HULIS had higher molecular weight and aromaticity in winter than in summer.HULIS-n dominated in the total light absorption of HULIS+HP-WSOC in both winter(73.08%)and summer(48.57%).Overall,the results on the carbon content,optical properties,and functional groups of WSOCs with differing polarity can improve un-derstanding of environmental and climatic effects. 展开更多
关键词 Humic-like substances(HULIS) AROMATICITY Fourier-transform infrared(FTIR) spectroscopy Light absorbance
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基于响应面法的粉煤灰-电石渣基地聚物的砂浆配比优化
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作者 王劲松 陈瑾 +3 位作者 但理 欧阳高尚 杜可杰 岳喜祥 《中国粉体技术》 CAS CSCD 2024年第4期69-80,共12页
【目的】为改善粉煤灰-电石渣基地聚物砂浆室温养护下的力学性能,实现工业固废粉煤灰和电石渣的资源再利用。【方法】利用单因素试验确定电石渣的最优掺量,初步确定粉煤灰-电石渣基地聚物砂浆的最优取值范围,然后以NaOH溶液浓度、液固... 【目的】为改善粉煤灰-电石渣基地聚物砂浆室温养护下的力学性能,实现工业固废粉煤灰和电石渣的资源再利用。【方法】利用单因素试验确定电石渣的最优掺量,初步确定粉煤灰-电石渣基地聚物砂浆的最优取值范围,然后以NaOH溶液浓度、液固比、水玻璃与NaOH溶液质量比为自变量因素,以砂浆28 d的抗压强度和抗折强度为响应值,进行响应面法实验,对粉煤灰-电石渣基地聚物砂浆配合比进行优化,并进行微观机制解释。【结果】响应面法能较为准确地优化粉煤灰-电石渣基地聚物砂浆配合比,当粉煤灰和电石渣的质量比为7∶3、NaOH溶液浓度为10 mol/L、液固比(质量比)为0.62、水玻璃与NaOH溶液质量比为2.3时,粉煤灰-电石渣基地聚物砂浆综合性能最优。【结论】在最优配比时,粉煤灰-电石渣基地聚物砂浆的水化产物以水合硅酸钙凝胶、水化硅铝酸钙凝胶为主,并随着固化时间的延长,粉煤灰-电石渣基地聚物体系的微观结构中凝胶含量增加,表现出更高的致密性以及更好的宏观力学性能,粉煤灰-电石渣基地聚物砂浆的综合力学性能及施工性能得以提高。 展开更多
关键词 响应面法 粉煤灰 电石渣 配比优化
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Ni基催化剂用于制备生物燃料的综合实验设计
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作者 李丹 辛慧 衣晓凤 《大学化学》 CAS 2024年第8期204-211,共8页
设计了不同晶粒尺寸的Ni纳米粒子催化剂及其制备生物燃料的综合化学实验。通过常规浸渍法制备了Ni/CeO_(2)、Ni/CeO_(2)-SiO_(2)和Ni/SiO_(2)三种纳米催化材料,借助X射线粉末衍射(XRD),X射线光电子能谱(XPS)和透射电子显微镜(TEM)等对... 设计了不同晶粒尺寸的Ni纳米粒子催化剂及其制备生物燃料的综合化学实验。通过常规浸渍法制备了Ni/CeO_(2)、Ni/CeO_(2)-SiO_(2)和Ni/SiO_(2)三种纳米催化材料,借助X射线粉末衍射(XRD),X射线光电子能谱(XPS)和透射电子显微镜(TEM)等对其进行了物理化学性质表征。通过参与催化剂合成、结构表征及其性能评价的全链条科研基本训练过程,不仅能够培养学生的综合实验技能,还能提升其科研素养,启发学生发现物质结构与性能之间内在规律,激发学生对探索未知科学领域的兴趣。该实验以“能源危机”为话题开展课程思政,加强学生对我国能源与环境危机现状的认识,引导学生从自我做起爱护环境。 展开更多
关键词 NI基催化剂 脱氧催化剂 生物燃料
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Double-stranded DNA-nucleic acid dye complex-sensitized biocatalytic photosynthesis:Base pairing-switched regeneration of nicotinamide cofactor
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作者 Zhen Dong Yanying Wang +1 位作者 dan li Peng Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期618-624,共7页
Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable energy.It is thus important to develop light antennas with both good light har-vesting and... Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable energy.It is thus important to develop light antennas with both good light har-vesting and efficient electron transfer.Herein,the intriguing electrical conductivity of dsDNA and its host effect(for nucleic acid dyes to harvest light)were explored simultaneously to develop a dsDNA-based light antenna for photo-biocatalysis.With SYBR Green I(SG)as the example of the nucleic acid dye,the proposed SG-dsDNA system was found to be capable for visible-light-driven reduced nicotinamide adenine dinucleotide(NADH)regeneration,and the turnover frequency of which(1.35 min^(-1))exceeded most of the existing photocatalytic systems.Since SG can only be hosted by dsDNA,meanwhile dsDNA can be formed through hybridization between single strand DNA and its complementary strand,the pro-posed system adds an extra control of the photocatalytic activity(DNA base pairing-based switch).When integrating the SG-dsDNA system with NADH-dependent horse liver alcohol dehydrogenase(HLADH),successful synthesis of 2-phenylpropanol(a crucial intermediates of profens manufacturing)was achieved. 展开更多
关键词 PHOTOSYNTHESIS DSDNA SYBRGreenI TICT 2-phenylpropanol
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