检索结果-南通市图书馆

Earth and Planetary Physics 2024年第2期8卷 368-374页

作者： LuHuai Jiao Xin Ma YuanNong Zhang TaiFeng Jin Song fu BinBin Ni Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

The energy spectrum of energetic electrons is a key factor representing the dynamic variations of Earth’s Van Allen radiation *** measurements have indicated that the commonly used Maxwellian and Kappa distributions are inadequate for capturing the realistic spectral distributions of radiation belt *** we adopt the Kappa-type(KT)distribution as the fitting function and perform a statistical analysis to investigate the radiation belt electron flux spectra observed by the Van Allen *** calculating the optimal values of the key KT distribution parameters(i.e.,κandθ2)from the observed spectral shapes,we fit the radiation belt electron fluxes at different L-shells under different geomagnetic *** this manner,we obtain typical values of the KT distribution parameters,which are statistically feasible for modeling the radiation belt electron flux profiles during either geomagnetically quiet or active periods.A comparison of the KT distribution model results with those using the Maxwellian or Kappa distribution reveals the advantage of the KT distribution for studying the overall properties of the radiation belt electron spectral distribution,which has important implications for deepening the current understanding of the radiation belt electron dynamics under evolving geomagnetic conditions.

关键词： radiation belt electron Kappa-type distribution fitting geomagnetic storm

A green cross-linking method for the preparation of renewable threedimensional graphene sponges for efficient adsorption of Congo red dye

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第2期66卷 84-93页

作者： Zhuang Liu Bo Gao Haoyuan Han Yuling Li Haiyang fu Donghui Wei Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China

Graphene-based materials possess significant potential for the treatment of dye wastewater due to their exceptional adsorption properties toward stubborn ***,their utilization is hindered by high preparation costs,low yields,environmental pollution during synthesis,and challenges in regenerating the *** study proposes a novel approach to address these limitations by developing nitrogen-doped three-dimensional(3D)polyvinyl alcohol(PVA)crosslinked graphene sponges(N-PGA)using a cross-linking method with ammonium *** method offers a relatively mild,environmentally friendly *** carbonate serves as both a reducing and modifying agent,facilitating the formation of the intrinsic structure of N-PGA and acting as a nitrogen ***,PVA is utilized as the cross-linking *** results demonstrate that N-PGA exhibits a favorable internal 3D hierarchical porous structure and possesses robust mechanical *** measured specific surface area(BET)of N-PGA was as high as406.538 m^(2)·g^(-1),which was favorable for its efficient adsorption of Congo red(CR)dye *** an initial concentration of 50 mg·L^(-1),N-PGA achieved an impressive removal rate of 89.6%and an adsorption capacity of 112 mg·g^(-1)for CR ***,it retained 79%of its initial adsorption capacity after 10 cycles,demonstrating excellent regeneration *** summary,the synthesized N-PGA displays remarkable efficacy in the adsorption of CR dye in wastewater,opening up new possibilities for utilizing 3D porous graphene nanomaterials as efficient adsorbents in wastewater treatment.

关键词： Green chemistry Graphene sponge Adsorbents Adsorption Congo red Regeneration

Wireless electrical stimulation generated by piezoelectric nanomaterial promotes the dental pulp regeneration via regulating mitochondrial Ca^(2+)/PKA signaling pathway

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第1期168卷 24-34页

作者： Jianmao Zheng Jiyuan Zuo Cairong Xiao Qining Guo Xiaobin fu Chengyun Ning Peng Yu Guangdong Provincial Key Laboratory of Stomatology Hospital of StomatologySun Yat-Sen UniversityGuangzhou 510080China School of Materials Science and Engineering National Engineering Research Center for Tissue Restoration and ReconstructionSouth China University of TechnologyGuangzhou 510641China

The induction of dental pulp stem cells(DPSCs)into odontogenic differentiation is a cutting-edge method of dental pulp regeneration ***,it remains a challenge to develop biomaterials and ther-apies that can induce odontogenic ***,we propose a wireless electrical stimulation strat-egy to induce DPSCs odontogenic differentiation via K_(0.5)Na_(0.5)NbO_(3)piezoelectric nanoparticles(KNN)and polarized KNN(PKNN),which can be endocytosed by *** vitro,several odontogenic differentiation indexes were also increased in DPSCs treated with KNN and PKNN,and the increase was more obvious in the PKNN *** wireless electrical field promoted mitochondrial calcium concentration via mitochondrial calcium unidirectional transporter(MCU),increased the production of adenosine triphos-phate(ATP),and induced odontogenic differentiation through the activation of the cAMP-PKA signaling *** vivo,dental pulp-like tissue was induced by electrical stimulation wirelessly with KNN and PKNN,which was more clinically friendly compared with the wired device,and the induction was more obvious in the PKNN group consistent with in vitro *** conclusion,this work demonstrates the potential of PKNN as an effective stimulus that can induce odontogenic differentiation of DPSCs and be applied to dental pulp regeneration treatment.

关键词： Piezoelectric nanoparticles Dental pulp stem cells Odontogenic differentiation

Probiotic cocktails accelerate baicalin metabolism in the ileum to modulate intestinal health in broiler chickens

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2024年第2期15卷 779-794页

作者： Mingkun Gao Chaoyong Liao Jianyang fu Zhonghua Ning Zengpeng Lv Yuming Guo State Key Laboratory of Animal Nutrition and Feeding College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China National Engineering Laboratory for Animal Breeding College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Background Baicalin and probiotic cocktails are promising feed additives with broad application *** probiotic cocktails are known to enhance intestinal health,the potential synergistic impact of combining baicalin with probiotic cocktails on the gut health of broiler chickens remains largely ***,this study aims to investigate the influence of the combined administration of baicalin and probiotic cocktails on the composition of ileal and cecal microbiota in broiler chickens to elucidate the underlying mechanisms responsible for the healthpromoting *** A total of 3201-day-old male Arbor Acres broilers were divided into 4 groups,each with 8 replicates of 10 chicks per *** a period of 42 d,the birds were fed a basal diet or the same diet supplemented with 37.5 g/t baicalin(BC),1,000 g/t probiotic cocktails(PC),or a combination of both BC(37.5 g/t)and PC(1,000 g/t).The results demonstrated that BC+PC exhibited positive synergistic effects,enhancing intestinal morphology,immune function,and barrier *** was evidenced by increased VH/CD ratio,sIgA levels,and upregulated expression of occludin and claudin-1(P<0.05).16S rRNA analysis indicated that PC potentiated the effects of BC,particularly in the ileum,where BC+PC significantly increased theα-diversity of the ileal microbiota,altered itsβ-diversity,and increased the relative abundance of Flavonifractor(P<0.05),a flavonoid-metabolizing ***,Flavonifractor positively correlated with chicken ileum crypt depth(P<0.05).While BC+PC had a limited effect on cecal microbiota structure,the PC group had a very similar microbial composition to BC+PC,suggesting that the effect of PC at the distal end of the gut overshadowed those of *** We demonstrated the synergistic enhancement of gut health regulation in broiler chickens by combining baicalin and probiotic *** cocktails enhanced the effects of baicalin and accelerated its metab

关键词： Baicalin Gut health Ileal microbiota Probiotic cocktails Synergistic effects

Balanced Polysulfide Containment and Lithium Ion Transport in Lithium-Sulfur Batteries via Nitrogen-doped Carbon Hollow Multi-shelled Structures on Modified Separators

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第4期40卷 690-698页

作者： RAO fu XIAO Qian WEI Yanze WANG Jiangyan YU Ranbo WANG Dan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190P.R.China Key Laboratory of Biopharmaceutical Preparation and Delivery Chinese Academy of SciencesBeijing100190P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science&Technology BeijingBeijing100083P.R.China

Representing the next-generation technology in lithium-ion batteries,lithium-sulfur(Li-S)batteries offer increased specific energy without relying on scarce metals like nickel and cobalt,but suffer from a low practical specific energy due to poor conductivity and a short lifespan due to the shuttle effect of *** the confinement of polysulfides and the transport of lithium ions requires highly elaborate modifiers for *** multi-shelled structures(HoMSs)show promise as hierarchical mesostructures for separators,offering multiple shell layers and internal cavities that effectively inhibit polysulfide *** design of these structures is crucial to address these challenges *** this study,nitrogen-doped carbon HoMS(NC HoMS)was created using polymer templates through a precisely controlled polymerization *** featuring NC HoMS-modified separators exhibit improved capacity and cycling stability in comparison to those utilizing commercial ***,triple-shelled NC HoMS strikes a balance in polysulfide containment and lithium ion *** a sulfur loading of 6.34 mg/cm^(2),the Li-S battery can consistently complete 100 charge-discharge cycles,starting with a discharge capacity of 966.4 mA·h/g with a 75.8%capacity retention *** HoMS holds potential as the separator modifier in addressing the polysulfide shuttle problem and facilitating the Li-ion transportation for advanced Li-S batteries.

关键词： Hollow multi-shelled structure Carbon material Li-S battery Separator modification Shuttle effect

Biochanin A attenuates spinal cord injury in rats during early stages by inhibiting oxidative stress and inflammasome activation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第9期19卷 2050-2056页

作者： Xigong Li Jing fu Ming Guan Haifei Shi Wenming Pan Xianfeng Lou Department of Orthopedics The First Affiliated Hospital of Zhejiang UniversityHangzhouZhejiang ProvinceChina Department of Stomatology Xixi HospitalHangzhouZhejiang ProvinceChina Department of Orthopedics and Spine Surgerythe Affiliated Hospital of Xuzhou Medical Schoolthe Second People’s Hospital of ChangshuChangshuJiangsu ProvinceChina

Previous studies have shown that Biochanin A,a flavonoid compound with estrogenic effects,can serve as a neuroprotective agent in the context of cerebral ischemia/reperfusion injury;howeve r,its effect on spinal cord injury is still unclea r. In this study,a rat model of spinal cord injury was established using the heavy o bject impact method,and the rats were then treated with Biochanin A(40 mg/kg) via intrape ritoneal injection for 14 consecutive *** res ults showed that Biochanin A effectively alleviated spinal cord neuronal injury and spinal co rd tissue injury,reduced inflammation and oxidative stress in spinal cord neuro ns,and reduced apoptosis and *** addition,Biochanin A inhibited the expression of inflammasome-related proteins(ASC,NLRP3,and GSDMD)and the Toll-like receptor 4/nuclear factor-κB pathway,activated the Nrf2/heme oxygenase 1 signaling pathway,and increased the expression of the autophagy markers LC3 Ⅱ,Beclin-1,and *** r,the therapeutic effects of Biochanin A on early post-s pinal cord injury were similar to those of *** findings suggest that Biochanin A protected neurons in the injured spinal cord through the Toll-like receptor 4/nuclear factor κB and Nrf2/heme oxygenase 1 signaling *** findings suggest that Biochanin A can alleviate post-spinal cord injury at an early stage.

关键词： apoptosis autophagy Biochanin A heme oxygenase 1 inflammation Nrf2 protein nuclear factor kappa-B oxidative stress spinal cord injury Toll-like receptor 4

The anisotropy of suprathermal electrons in the Martian ionosphere

在线全文

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2024年第3期8卷 459-471页

作者： YuTian Cao Jun Cui XiaoShu Wu WenJun Liang RuiQi fu HaoYu Lu Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082China Key Laboratory of Geospace Environment University of Science&Technology of ChinaChinese Academy of SciencesHefei 230026China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China School of Space and Environment Beihang UniversityBeijing 102206China

Suprathermal electrons are an important population of the Martian ionosphere, either produced by photoionization of atmospheric neutrals or supplied from the Solar Wind (SW). This study is dedicated to an in-depth investigation of the pitch angle distribution of suprathermal electrons at two representative energies, 19−55 eV and 124−356 eV, using the extensive measurements made by the Solar Wind Electron Analyzer on board the Mars Atmosphere and Volatile Evolution. Throughout the study, we focus on the overall degree of anisotropy, defined as the standard deviation of suprathermal electron intensity among different directions which is normalized by the mean omni-directional intensity. The available data reveal the following characteristics: (1) In general, low energy electrons are more isotropic than high energy electrons, and dayside electrons are more isotropic than nightside electrons;(2) On the dayside, the anisotropy increases with increasing altitude at low energies but remains roughly constant at high energies, whereas on the nightside, the anisotropy decreases with increasing altitude at all energies;(3) Electrons tend to be more isotropic in strongly magnetized regions than in weakly magnetized regions, especially on the nightside. These observations indicate that the anisotropy is a useful diagnostic of suprathermal electron transport, for which the conversion between the parallel and perpendicular momenta as required by the conservation of the first adiabatic invariant, along with the atmospheric absorption at low altitudes, are two crucial factors modulating the observed variation of the anisotropy. Our analysis also highlights the different roles on the observed anisotropy exerted by suprathermal electrons of different origins.

关键词： Mars ionosphere suprathermal electron pitch angle distribution

Mapping out the reaction network of humin formation at the initial stage of fructose dehydration in water

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2024年第6期9卷 1016-1026页

作者： Xing fu Yexin Hu Ping Hu Hui Li Shuguang Xu Liangfang Zhu Changwei Hu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan610064China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengduSichuan611137China

The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural(HMF)in ***,a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water is delineated by combined experimental,spectroscopic,and theoretical *** bimolecular reaction pathways to build up soluble humins are *** is,the intermolecular etherification of β-furanose at room temperature initiates the C12 path,whereas the C-C cleavage of a-furanose at 130-150℃ leads to C11 path,and that of open-chain fructose at 180℃ to C11' *** successive intramolecular dehydrations and condensations of the as-formed bimolecular intermediates lead to three types of soluble *** show that the C12 path could be restrained by using HCl or AlCl_(3) catalyst,and both the C12 and C110 paths could be effectively inhibited by adding THF as a co-solvent or accelerating heating rate via microwave heating.

关键词： Carbohydrates 5-hydroxymethylfurfural Reaction network Soluble humins Tautomer

Discharge evolution law of debris flow based on a sharp bend physical modeling test

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2024年第6期21卷 1904-1915页

作者： LU Ming SUN Hao LIU Jinfeng Abrar HUSSAIN SHANG Yuqi fu Hang Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of SciencesChengdu 610041China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

For the basins with debris flow development,its channel terrain exhibits a tortuous shape,which significantly restricts the movement of debris flows and leads to severe erosion effects on the concave ***,this study aims to analyze the shear force of debris flows within the bend *** established the relationship between the shear force and bend curvature through laboratory *** the long-term erosion by debris flows,the curvature radius of bends gradually increases,however,when this increasing trend reaches an equilibrium state with the intensity of debris flow discharge,there will be no significant change in curvature *** general,the activity pattern and discharges of debris flows would remain relatively ***,we can infer the magnitude of debris flow discharges from the terrain parameters of the bend channel.

关键词： Debris flow discharge Erosion effect Bend channel Curvature radius

Multi-scale modeling for prediction of mechanical performance in brazed GH99 thin-walled structure

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第7期37卷 550-563页

作者： Yazhou LIU Shengpeng HU Yanyu SONG Wei fu Xiaoguo SONG Ning GUO Weimin LONG State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Institute of Shipbuilding Technology Weihai 264209China China Machinery Intelligent Equipment Innovation Research Institute(Ningbo)Co. Ltd.Ningbo 315700China

Superalloy thin-walled structures are achieved mainly by brazing,but the deformation process of brazed joints is non-uniform,making it a challenging research *** paper records a thorough investigation of the effect of brazing parameters on the microstructure of joints and its mechanical properties,which mainly inquires into the deformation and fracture mechanisms in the shearing process of GH99/BNi-5a/GH99 *** macroscopic-microscopic deformation mechanism of the brazing interface during shearing was studied by Crystal Plasticity(CP)and Molecular Dynamics(MD)on the basis of the optimal brazing *** experimental results show that the brazing interface is mainly formed by(Ni,Cr,Co)(s,s)and possesses a shear strength of approximately 546 *** shearing fracture of the brazed joint occurs along the brazing seam,displaying the characteristics of intergranular *** simulations show that dislocations disassociate and transform into fine twinning with increased *** simulated the shear deformation process of the brazed *** multiscale simulation results are consistent with the experimental *** mechanical properties of thin-walled materials for brazing are predicted using MD and CP methods.

关键词： Multi-scale modeling Brazing Shear mechanisms Crystal plasticity GH99 superalloy