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A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期 145-158页

作者： guo Xingduo li Yinran li Rennian MA Yulong WEI Kui College of Energy and Power Engineering Lanzhou University of Technology Key Laboratory of Fluid Machinery and Systems Gansu Provincial Technology Centre for Wind Turbines

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL) wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

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Decarburization Thermodynamics of High-Carbon Ferromanganese Powders During Gas-Solid Fluidization Process

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Journal of Iron and Steel Research International 2012年第5期19卷 1-8页

作者： guo li-na CHEN Jin ZHANG Meng liANG Min College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China

Thermodynamic conditions of reactions between high-carbon ferromanganese powders and gas decarbonizers like O2, CO2 and water vapor were studied by thermodynamic calculation. In O2, CO2 and water vapor atmosphere, high-carbon ferromanganese powders were decarburized in a fluidized bed. When the temperature is respectively higher than 273, 1 226 and 1 312 K, the gas-solid decarburization reaction will occur between ferromanganese carbide on the surface of the high-carbon ferromanganese powders and different gas decarbonizers. Since metal manganese is easy to be oxidized by O2, CO2 or water vapor, the decarburization reaction will transfer into a solid-solid phase reaction of ferromanganese carbide and ferromanganese oxide, promoting external diffusion of carbon to achieve a further decarburization of high-carbon ferromanganese powders.

关键词： gas-solid fluidization high carbon ferromanganese powders gas decarbonizer solid-phase decarburization

BOUNDS ON AVERAGE CONTROLLED DIRECT EFFECTS WITH AN UNOBSERVED RESPONSE VARIABLE

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Journal of Systems Science & Complexity 2011年第6期24卷 1154-1164页

作者： na SHAN Jianhua guo Key Laboratory for Applied Statistics of Ministry of Education School of Mathematics and Statistics Northeast Normal University Changchun 130024 China School of Basic Science Changchun University of Technology Changchun 130012 China

This paper considers the problem of estimating the bounds on the average controlled direct effects （ACDEs） of a treatment variable on an unobserved response variable in the presence of unobserved confounders between an intermediate variable and the response variable. When the response variable is observed, Cai, et al.（2008） derived the formulas for the sharp bounds on the ACDEs. When the response variable is unobserved, the authors propose a graphical criterion for selecting variables affected by the response variable to derive the formulas for the bounds on the ACDEs, which is an extension of the result of Kuroki（2005） to ACDEs. The results enable us not only to judge from the graph structure whether the bounds on the ACDEs can be expressed through observed variables when the response variable is unobserved, but also to provide their formulas when the answer is affirmative.

关键词： Average controlled direct effect causal network d-separation

Deciphering the structural evolution and real active ingredients of iron oxides in photocatalytic CO_(2)hydrogenation

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Chinese Journal of Structural Chemistry 2024年第8期43卷 27-37页

作者： Mengjun Zhao Yuhao guo na li Tingjiang Yan Key Laboratory of Catalytic Conversion and Clean Energy in Universities of Shandong Province School of Chemistry and Chemical EngineeringQufu Normal UniversityQufu273165PR China College of Chemistry and Chemical Engineering Shaanxi University of Science and TechnologyXi'an710021PR China

Photocatalytic CO_(2)hydrogenation reactions can produce high-value-added chemicals for industry,solving the environmental problems caused by excessive CO_(2)*** oxides are commonly used in photocatalytic reactions due to their various structures and suitable band ***,the structural evolution and real active components during photocatalytic CO_(2)hydrogenation reaction are rarely ***,a variety of iron oxides including a-Fe_(2)O_(3),y-Fe_(2)O_(3),Fe_(3)O_(4)and FeO were derived from Prussian blue precursors to investigate the CO_(2)hydrogenation performance,structural evolution and active ***,the typical a-andγ-Fe_(2)O_(3)are converted to Fe_(3)O_(4)during the reaction,while Fe/Fe_(x)O_(y)remains structurally ***,it is confirmed that Fe_(3)O_(4)is the main active component for CO production and the formation of hydrocarbons(CH_(4)and C_(2)-C_(4))are highly dependent on the Fe/Fe_(x)O_(y)*** optimal yields of CO,CH_(4)and C_(2)-C_(4)hydrocarbons over the best catalyst(FeFe-550)can achieve 4 mmol g^(-1)h^(-1),350μmol g^(-1)h^(-1)and 150μmol g^(-1)h^(-1),respectively due to their suitable metal/oxide component *** work examines the structural evolution of different iron oxide catalysts in the photocatalytic CO_(2)hydrogenation reaction,identifies the active components as well as reveals the relationship between components and the products,and offers valuable insights into the efficient utilization of CO_(2).

关键词： Iron oxides Photocatalysis CO_(2)hydrogenation Structural evolution

A new neuroprotective bakkenolide from the rhizome of Petasites tricholobus

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Chinese Chemical Letters 2008年第7期19卷 841-844页

作者： na Zhang Mei li guo Ge Zhang Run Ping li Department of Pharmacognosy School of Pharmacy Second Military Medical University Shanghai 200433 China Department of Diving Medicine Faculty of Naval Medicine Second Military Medical University Shanghai 200433 China

A new bakkenolide-type compound, bakkenolide-Va（1）, was isolated from the rhizome of Petasites tricholobus. The structure was characterized on the basis of various NMR （1H, 13C, 1H-1H COSY, HMQC, HMBC and NOESY） and mass spectrometry data. The neuroprotective activity of bakkenolide-Va was investigated in primarily cultured neurons treated by hypoxia-ghicose deprivation and various types of oxidative insults.

关键词： Petasites tricholobus Compositae Bakkenofide-Va Neuroprotection

The complex effects of miR-146a in the pathogenesis of Alzheimer's disease

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Neural Regeneration Research 2025年第5期20卷 1309-1323页

作者： Yunfan Long Jiajia liu Yu Wang Haidong guo guohong Cui Department of Neurology Shanghai No.9 People’s HospitalShanghai Jiaotong University School of MedicineShanghaiChina Academy of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina School of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina Department of Neurology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghaiChina

Alzheimer's disease is a neurodegenerative disorder characterized by cognitive dysfunction and behavioral *** plaques formed through the extracellular deposition of amyloid-βproteins,as well as neurofibrillary tangles formed by the intracellular deposition of hyperphosphorylated tau proteins,comprise two typical pathological features of Alzheimer's *** symptomatic treatment,there are no effective therapies for delaying Alzheimer's disease ***(miR)are small,non-coding Rnas that negatively regulate gene expression at the transcriptional and translational levels and play important roles in multiple physiological and pathological ***,miR-146a,a NF-κB-regulated gene,has been extensively implicated in the development of Alzheimer's disease through several *** has demonstrated substantial dysregulation of miR-146a both during the initial phases and throughout the progression of this *** R-146a is believed to reduce amyloid-βdeposition and tau protein hyperphosphorylation through the TLR/IRAK1/TRAF6 pathway;however,there is also evidence supporting that it can promote these processes through many other pathways,thus exacerbating the pathological manifestations of Alzheimer's *** has been widely reported that miR-146a mediates synaptic dysfunction,mitochondrial dysfunction,and neuronal death by targeting m Rnas encoding synapticrelated proteins,mitochondrial-related proteins,and membrane proteins,as well as other *** the impact on glial cells,miR-146a also exhibits differential *** one hand,it causes widespread and sustained inflammation through certain pathways,while on the other hand,it can reverse the polarization of astrocytes and microglia,alleviate neuroinflammation,and promote oligodendrocyte progenitor cell differentiation,thus maintaining the normal function of the myelin sheath and exerting a protective effect on *** this review,we provide a

关键词： Alzheimer's disease amyloid-β glial cells microRnas miR-146a neuroinflammatory

In situ synthesis of red fluorescent gold nanoclusters with enzyme-like activity for oxidative stress amplification in chemodynamic therapy

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Chinese Chemical Letters 2022年第3期33卷 1331-1336页

作者： Wenying Mi Shuang Tang Shaoshi guo Hejing li na Shao College of Chemistry Beijing Normal UniversityBeijing 100875China

Chemodynamic therapy (CDT) has attracted tremendous interest in cancer therapy because it is independent of oxygen and photoirradiation. However, the therapeutic efficacy of CDT is restricted by insufficient H_(2)O_(2) levels in tumor cells. Herein, employing endogenous GSH as a template and cationic polymeric chitosan (CS) as crosslinker and stabilizer exhibiting easy cell uptake, red luminescent gold nanoclusters (denoted CS-GSH@AuNCs) were successfully synthesized in HeLa cells. The in situ synthesized CS-GSH@AuNCs exhibited both superoxidase dismutase (SOD) and peroxidase (POD)-like activity, which could promote the production of H_(2)O_(2) from superoxide anion radicals (O_(2)^(·-)) and then ^(·)OH. The combination of GSH elimination and H_(2)O_(2) elevation boosted the generation of ^(·)OH, which could trigger cancer cell apoptosis and death. The enzyme-like activity of CS-GSH@AuNCs could be effectively activated under acidic conditions, and showed a high killing effect on tumor cells but minimal toxicity to normal cells. The developed GSH consumption and ^(·)OH promotion theranostic platform is an innovative route for enhanced CDT by the amplification of oxidative stress.

关键词： Chemodynamic therapy In situ synthesis Gold nanoclusters Superoxidase dismutase and peroxidase(POD)-like activity Oxidative stress amplification

Complete Mitochondrial Genome of the Steppe Ribbon Racer(Psammophis lineolatus):The First Representative from the Snake Family Psammophiidae and its Phylogenetic Implications

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Asian Herpetological Research 2021年第3期12卷 295-307页

作者： Minli CHEN Jinlong liU Jun li na WU Xianguang guo Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina University of Chinese Academy of Sciences Beijing 100049China College of life Science and Technology Xinjiang UniversityUrumqi 830046XinjiangChina

Comparisons of vertebrate mitochondrial genomes(mitogenomes)may yield significant insights into the evolution of organisms and ***,no complete mitogenome from the snake family Psammophiidae has been *** this study,we sequenced and annotated the complete mitogenome of Psammophis lineolatus,representing the first mitogenome of *** total length is 17166 bp,consisting of 13 protein-coding genes(PCGs),22 transfer Rnas(tRnas),two ribosomal Rnas(12 S rRna and16 S rRna),and duplicate control regions(CRs).This gene arrangement belongs to the TypeⅢpattern,which is a widely shared gene order in Alethinophidian *** tRnas exhibit cloverleaf structures with the exception of tRna-Ser^(AGY) and tRna-Pro,which lack a dihydrouridine(DHU)arm/stem and TΨC loop,*** 13 PCGs include five start codons(ATG,GTG,ATA,ATT,and ATC),two complete stop codons(TAA and AGG),and two incomplete stop codon(T--and TA-).In addition,the Ka/Ks ratios indicate that all PCGs had undergone a strong purifying *** types of CR domains rearrangement occurred among eight species of *** phylogenetic reconstructions with both Bayesian inference and maximum likelihood methods support the placement of Psammophiidae in the Elapoidea superfamily,with Homalopsidae being the sister taxon to Elapoidea and ***,the sister taxon of Psammophiidae is unclear due to the availability of Elapoidea mitogenomes being limited to the family *** mitogenomes from different taxonomic groups in Elapoidea are needed to better understand the phylogenetic relationships within Elapoidea.

关键词： mitochondrial genome phylogenetic relationships Psammophis lineolatus Psammophiidae purifying selection

Successful rescue of acute liver failure and hemophagocytic lymphohistiocytosis following varicella infection: A case report and review of literature

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World Journal of Clinical Cases 2018年第13期6卷 659-665页

作者： li-na Zhang Wei guo Ji-Hong Zhu Yang guo Department of Rheumatology and Immunology Peking University People’s Hospital Department of Emergency Peking University People’s Hospital

Herein we report a case of acute liver failure(ALF) and hemophagocytic lymphohistiocytosis(HLH) induced by varicella infection, successfully rescued by a combination therapy of acyclovir, supportive care, and immunosuppression with dexamethasone and etoposide. A previously healthy 16-year-old boy presented with generalized rash, fever, severe abdominal pain, and abnormal liver function within 4 d. Chickenpox was suspected, and acyclovir and intravenous immunoglobulin were started on admission. However, the patient's condition deteriorated overnight with soaring transaminases, severe coagulopathy and encephalopathy. On the fourth day of admission, pancytopenia emerged, accompanied by hypofibrinogenemia and hyperferritinemia. The patient was diagnosed with ALF. He also met the diagnostic criteria of HLH according to the HLH-2004 guideline. Polymerase chain reaction(PCR) amplifications of varicella-zoster virus(VZV) were positive, confirming that VZV was a causative trigger for ALF and HLH. In view of the devastating immune activation in HLH, immunosuppression therapy with dexamethasone and etoposide was administered, in addition to high dose acyclovir. The patient's symptoms improved dramatically and he finally made a full recovery. To our knowledge, this is only the second report of a successful rescue of ALF associated with HLH, without resorting to liver transplantation. The first case was reported in a neonate infected by herpes simplex virus-1. However, survival data in older children and adults are lacking, most of whom died or underwent liver transplantation. Our report emphasizes the clinical vigilance for the possible presence of HLH, and the necessity of extensive investigation for underlying etiologies in patients presenting with indeterminate ALF. Early initiation of specific therapy targeting the underlying etiology, and watchful immunosuppression such as dexamethasone and etoposide, together with supportive therapy, are of crucial importance in this life

关键词： Acute liver failure Immune dysregulation Hyperferritinemia Hemophagocytic lymphohistiocytosis Varicella infection Skin rash