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On implications of somatostatin in diabetic retinopathy
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作者 Yanhong Fang Qionghua Wang +3 位作者 Youjian Li Li Zeng jian liu Kepeng Ou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1984-1990,共7页
Somatostatin,a naturally produced neuroprotective peptide,depresses excitatory neurotransmission and exerts anti-proliferative and anti-inflammatory effects on the retina.In this review,we summarize the progress of so... Somatostatin,a naturally produced neuroprotective peptide,depresses excitatory neurotransmission and exerts anti-proliferative and anti-inflammatory effects on the retina.In this review,we summarize the progress of somatostatin treatment of diabetic retinopathy through analysis of relevant studies published from February 2019 to February 2023 extracted from the PubMed and Google Scholar databases.Insufficient neuroprotection,which occurs as a consequence of declined expression or dysregulation of retinal somatostatin in the very early stages of diabetic retinopathy,triggers retinal neurovascular unit impairment and microvascular damage.Somatostatin replacement is a promising treatment for retinal neurodegeneration in diabetic retinopathy.Numerous pre-clinical and clinical trials of somatostatin analog treatment for early diabetic retinopathy have been initiated.In one such trial(EUROCONDOR),topical administration of somatostatin was found to exert neuroprotective effects in patients with pre-existing retinal neurodysfunction,but had no impact on the onset of diabetic retinopathy.Overall,we concluded that somatostatin restoration may be especially beneficial for the growing population of patients with early-stage retinopathy.In order to achieve early prevention of diabetic retinopathy initiation,and thereby salvage visual function before the appearance of moderate non-proliferative diabetic retinopathy,several issues need to be addressed.These include the needs to:a)update and standardize the retinal screening scheme to incorporate the detection of early neurodegeneration,b)identify patient subgroups who would benefit from somatostatin analog supplementation,c)elucidate the interactions of somatostatin,particularly exogenously-delivered somatostatin analogs,with other retinal peptides in the context of hyperglycemia,and d)design safe,feasible,low cost,and effective administration routes. 展开更多
关键词 diabetes retinopathy EXCITOTOXICITY growth hormone insulin like growth factor irisin NEURODEGENERATION NEUROINFLAMMATION neuroprotection neurovascular unit OCTREOTIDE oxidative stress SOMATOSTATIN
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Ca and Sr co-doping induced oxygen vacancies in 3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts for boosting low-temperature oxidative coupling of methane
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作者 Tongtong Wu Yuechang Wei +5 位作者 Jing Xiong Yitao Yang Zhenpeng Wang Dawei Han Zhen Zhao jian liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期331-344,共14页
It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(... It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(A_(2)B_(2)O_(7)-type)catalysts with disordered defective cubic fluorite phased structure were successfully prepared by a colloidal crystal template method.3DOM structure promotes the accessibility of the gaseous reactants(O2and CH4)to the active sites.The co-doping of Ca and Sr ions in La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts improved the formation of oxygen vacancies,thereby leading to increased density of surface-active oxygen species(O_(2)^(-))for the activation of CH4and the formation of C2products(C2H6and C2H4).3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts exhibit high catalytic activity for OCM at low temperature.3DOM La1.7Sr0.3Ce1.7Ca0.3O7-δcatalyst with the highest density of O_(2)^(-)species exhibited the highest catalytic activity for low-temperature OCM,i.e.,its CH4conversion,selectivity and yield of C2products at 650℃are 32.2%,66.1%and 21.3%,respectively.The mechanism was proposed that the increase in surface oxygen vacancies induced by the co-doping of Ca and Sr ions boosts the key step of C-H bond breaking and C-C bond coupling in catalyzing low-temperature OCM.It is meaningful for the development of the low-temperature and high-efficient catalysts for OCM reaction in practical application. 展开更多
关键词 3DOM catalysts Ca ions Sr ions Low-temperature oxidative couplingof methane Oxygen vacancies O_(2)^(-) species
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Lithium-ion and solvent co-intercalation enhancing the energy density of fluorinated graphene cathode
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作者 Hao Wang Jie jiang +5 位作者 Pengyu Chen Zhenrui Wu Xiaobin Niu Chuying Ouyang jian liu Liping Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期208-215,I0006,共9页
Fluorinated carbons CF_xhold the highest theoretical energy density(e.g.,2180 W h kg^(-1)when x=1)among all cathode materials of lithium primary batteries.However,the low conductivity and severe polarization limit it ... Fluorinated carbons CF_xhold the highest theoretical energy density(e.g.,2180 W h kg^(-1)when x=1)among all cathode materials of lithium primary batteries.However,the low conductivity and severe polarization limit it to achieve its theory.In this study,we design a new electrolyte,namely 1 M LiBF_(4)DMSO:DOL(1:9 vol.),achieving a high energy density in Li/CF_xprimary cells.The DMSO with a small molecular size and high donor number successfully solvates Li^(+)into a defined Li^(+)-solvation structure.Such solvated Li^(+)can intercalate into the large-spacing carbon layers and achieve an improved capacity.Consequently,when discharged to 1.0 V,the CF_(1.12)cathode demonstrates a specific capacity of 1944 m A h g^(-1)with a specific energy density of 3793 W h kg^(-1).This strategy demonstrates that designing the electrolyte is powerful in improving the electrochemical performance of CF_(x) cathode. 展开更多
关键词 Fluorinated carbon Conversion reaction High-energy-density primary battery Li^(+)-solvation structure Solvent co-intercalation
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A general synthetic strategy for N, P co-doped graphene supported metal-rich noble metal phosphides for hydrogen generation
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作者 Jingwen Ma Xiang Li +6 位作者 Guangyu Lei Jun Wang Juan Wang jian liu Ming Ke Yang Li Chunwen Sun 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期152-162,共11页
The exploitation of electrocatalysts with high activity and durability for HER is desirable for future energy systems,but it is still a challenge.NMPs have attracted increasing attentions,but the preparation process o... The exploitation of electrocatalysts with high activity and durability for HER is desirable for future energy systems,but it is still a challenge.NMPs have attracted increasing attentions,but the preparation process often needs toxic regents or dangerous reaction conditions.Herein,we develop a general green method to fabricate metal-rich NMPs anchored on NPG through pyrolyzing DNA cross-linked complexes.The obtained Ru_(2) P-NPG exhibits an ultrasmall overpotential of 7 mV at 10 mA cm^(2) and ultralow Tafel slope of 33 mV dec^(-1) in 1.0 mol L?1 KOH,even better than that of commercial Pt/C.In addition,Ru 2 P-NPG also shows low overpotentials of 29 and 78 mV in 0.5 mol L^(-1) H_(2)SO_(4) and 1.0 mol L^(-1) PBS,respectively.The superior activity can be attributed to the ultrafine dispersion of Ru 2 P nanoparticles for more accessible sites,more defects formed for abundant active sites,the two-dimensional plane structure for accelerated electron transfer and mass transport,as well as the regulation of electron distribution of the catalyst.Moreover,the synthetic method can also be applied to prepare other metal-rich noble metal phosphides(Pd_(3)P-NPG and Rh_(2)P-NPG),which also exhibits high activity for HER.This work provides an effective strategy for designing NMP-based electrocatalysts. 展开更多
关键词 Noble metal phosphides ELECTROCATALYST Deoxyribonucleic acid Hydrogen evolution pH universal
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用于氨电氧化反应生成硝酸盐/亚硝酸盐的金属基电催化剂:过去、现在和未来
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作者 田芸睿 谭皓天 +4 位作者 李霞 贾晶晶 毛子贤 刘健 梁骥 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第1期25-50,共26页
亚硝酸盐和硝酸盐(统称为NO_(2/3)−)是工业、农业和食品工程中的重要物质.目前通过Ostwald氧化法制备亚硝酸盐和硝酸盐过程常常伴随着大量的能源消耗和温室气体排放.氨的电催化氧化是一种低排放和节能的低温工艺过程,可以持续生产NO_(2/... 亚硝酸盐和硝酸盐(统称为NO_(2/3)−)是工业、农业和食品工程中的重要物质.目前通过Ostwald氧化法制备亚硝酸盐和硝酸盐过程常常伴随着大量的能源消耗和温室气体排放.氨的电催化氧化是一种低排放和节能的低温工艺过程,可以持续生产NO_(2/3)−,避免了有害的N2O的形成,并且可以完全由可再生电力供电.目前对氨氧化反应的研究大多集中在氨裂解制氢和直接氨燃料电池上,而对氨转化为NO_(2/3)−的研究关注较少.因此,本文在总结近年来氨电催化工作的基础上,对催化剂的反应机理和设计思路进行了综述.本文从电催化氨氧化反应(AOR)可能的反应机理入手,介绍了AOR的反应条件、检测方法、原位表征方法以及理论计算的研究成果,在总结了影响AOR催化剂催化性能因素的基础上提出了近年来电催化剂的设计策略以及合成方法,并对未来氨领域的发展提出展望.首先,基于反应原理以及反应中间体的吸附路径等方面讨论了AOR的关键难点.然后,系统性总结了AOR的测试要求以及原位拉曼、原位红外、原位电化学质谱和原位X射线吸收光谱等技术在AOR机理研究中的重要作用,讨论了密度泛函理论对于研究AOR催化过程中的反应能垒和催化剂电子轨道分布的贡献.催化剂合金设计、界面工程、非晶化处理、单原子或双原子调制等可控策略有助于抑制副反应的进行以及电解过程中产生的腐蚀性物质对电极的破坏.最后,介绍了氨氧化在光、热以及生物催化领域的应用进展,提出了当前AOR所面临的挑战和解决策略,如将先进的材料设计与理论计算相结合,有助于寻找新的高性能AOR电催化剂.催化体系的改进和反应器的优化将加速大规模绿色、高效、低能耗电催化制备NO_(2/3)−的产业化.综上所述,AOR领域取得的进展说明氨电氧化制备NO_(2/3)−用于工业生产具有可行性,这为满足不断增长的NO_(2/3)−供应需求带来了新的机遇.尽管AOR仍面临性能不高、工艺不成熟等难题,但随着理论与实验研究的结合,原位表征技术不断地开发利用,未来高效、稳定的AOR催化剂会不断的出现.本文也为生成NO_(2/3)−的催化剂的研发提供理论参考. 展开更多
关键词 氨氧化反应 硝酸盐 亚硝酸盐 非贵金属催化剂
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Silicon-based optoelectronic heterogeneous integration for optical interconnection
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作者 李乐良 李贵柯 +5 位作者 张钊 刘剑 吴南健 王开友 祁楠 刘力源 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期1-9,共9页
The performance of optical interconnection has improved dramatically in recent years.Silicon-based optoelectronic heterogeneous integration is the key enabler to achieve high performance optical interconnection,which ... The performance of optical interconnection has improved dramatically in recent years.Silicon-based optoelectronic heterogeneous integration is the key enabler to achieve high performance optical interconnection,which not only provides the optical gain which is absent from native Si substrates and enables complete photonic functionalities on chip,but also improves the system performance through advanced heterogeneous integrated packaging.This paper reviews recent progress of silicon-based optoelectronic heterogeneous integration in high performance optical interconnection.The research status,development trend and application of ultra-low loss optical waveguides,high-speed detectors,high-speed modulators,lasers and 2D,2.5D,3D and monolithic integration are focused on. 展开更多
关键词 silicon-based heterogeneous integration heterogeneous integrated materials heterogeneous integrated packaging optical interconnection
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Spin gap in quasi-one-dimensional S=3/2 antiferromagnet CoTi2O5
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作者 徐浩航 刘庆元 +10 位作者 辛潮 申沁鑫 罗军 周睿 程金光 刘健 陶玲玲 刘志国 霍明学 王先杰 隋郁 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期609-617,共9页
Quasi-one-dimensional(1D)antiferromagnets are known to display intriguing phenomena especially when there is a spin gap in their spin-excitation spectra.Here we demonstrate that a spin gap exists in the quasi-1D Heise... Quasi-one-dimensional(1D)antiferromagnets are known to display intriguing phenomena especially when there is a spin gap in their spin-excitation spectra.Here we demonstrate that a spin gap exists in the quasi-1D Heisenberg antiferromagnet CoTi2O5 with highly ordered Co2+/Ti4+occupation,in which the Co2+ions with S=3/2 form a 1D spin chain along the a-axis.CoTi2O5 undergoes an antiferromagnetic transition at TN~24 K and exhibits obvious anisotropic magnetic susceptibility even in the paramagnetic region.Although a gapless magnetic ground state is usually expected in a quasi-1D Heisenberg antiferromagnet with half-integer spins,by analyzing the specific heat,the thermal conductivity,and the spin-lattice relaxation rate(1/T1)as a function of temperature,we found that a spin gap is opened in the spin-excitation spectrum of CoTi2O5 around TN,manifested by the rapid decrease of magnetic specific heat to zero,the double-peak characteristic in thermal conductivity,and the exponential decay of 1/T1 below TN.Both the magnetic measurements and the first-principles calculations results indicate that there is spin-orbit coupling in CoTi2O5,which induces the magnetic anisotropy in CoTi2O5,and then opens the spin gap at low temperature. 展开更多
关键词 quasi-one-dimensional antiferromagnet magnetic anisotropy spin gap
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Fixed-Time Consensus-Based Nash Equilibrium Seeking
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作者 Mengwei Sun jian liu +1 位作者 Lu Ren Changyin Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期267-269,共3页
Dear Editor,This letter examines the fixed-time stability of the Nash equilibrium(NE)in non-cooperative games.We propose a consensus-based NE seeking algorithm for situations where players do not have perfect informat... Dear Editor,This letter examines the fixed-time stability of the Nash equilibrium(NE)in non-cooperative games.We propose a consensus-based NE seeking algorithm for situations where players do not have perfect information and communicate via a topology graph.The proposed algorithm can achieve NE in a fixed time that does not depend on initial conditions and can be adjusted in advance. 展开更多
关键词 Fixed SEEKING LETTER
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Crossroads:Pathogenic role and therapeutic targets of neutrophil extracellular traps in rheumatoid arthritis
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作者 YANG LI jian liu +3 位作者 YUEDI HU CHENGZHI CONG YIMING CHEN QIAO ZHOU 《BIOCELL》 SCIE 2024年第1期9-19,共11页
Rheumatoid arthritis(RA)is a prevalent autoimmune disease whose main features include chronic synovial inflammation,bone destruction,and joint degeneration.Neutrophils are often considered to be the first responders t... Rheumatoid arthritis(RA)is a prevalent autoimmune disease whose main features include chronic synovial inflammation,bone destruction,and joint degeneration.Neutrophils are often considered to be the first responders to inflammation and are a key presence in the inflammatory milieu of RA.Neutrophil extracellular traps(NETs),a meshwork of DNA-histone complexes and proteins released by activated neutrophils,are widely involved in the pathophysiology of autoimmune diseases,especially RA,in addition to playing a key role in the neutrophil innate immune response.NETs have been found to be an important source of citrullinated autoantigen antibodies and inflammatory factor release,which can activate RA synovial fibroblasts(FLS)and cause joint damage.This article reviews the role of NETs in the pathophysiology of RA,demonstrating the application of multiple molecules with various therapies,with a view to informing the discovery and development of novel biomarkers and therapeutic targets for RA. 展开更多
关键词 Rheumatoid arthritis Neutrophil extracellular traps REVIEW
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Effect of Danzhijiangtang capsule on monocyte chemoattractant protein-1 mRNA expression in newly diagnosed diabetes subclinical vascular lesions 被引量:9
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作者 Zhao-Hui Fang Yan liu +6 位作者 Tao-Tao Bao Ying-Qun Ni jian liu Guo-Bin Shi Ji-Ping Wu Jun-Ping Yang Hong Zhang 《World Journal of Gastroenterology》 SCIE CAS 2013年第19期2963-2968,共6页
AIM:To investigate the effect of Danzhijiangtang capsule(DJC) on monocyte chemoattractant protein-1(MCP-1) mRNA expression in newly diagnosed type 2 diabetes mellitus(T2DM) subclinical vascular lesions.METHODS:Sixty-t... AIM:To investigate the effect of Danzhijiangtang capsule(DJC) on monocyte chemoattractant protein-1(MCP-1) mRNA expression in newly diagnosed type 2 diabetes mellitus(T2DM) subclinical vascular lesions.METHODS:Sixty-two patients with newly diagnosed T2DM subclinical vascular lesions were randomly divided into a control group and treatment group of 31 cases each.Oral antidiabetic therapy with routine western medicine was conducted in both groups,and the treatment group was additionally treated with DJCs.The treatment course for both groups was 12 wk.Before and after treatment,the total efficiency and traditional Chinese medicine(TCM) syndrome score were calculated.The fasting plasma glucose(FPG),2-h plasma glucose(2hPG),fasting insulin(FINS),insulin resistance index(IRI),hemoglobin(Hb)A1c,blood lipids,and hemorheology indices were determined.In addition,the levels of vascular endothelial growth factors including thrombomodulin(TM),von Willebrand factor(vWF),P-selectin and MCP-1 mRNA were determined.RESULTS:After 12 wk of treatment,the TCM syndrome score was significantly decreased compared to before treatment in both groups.After treatment,FPG,2hPG,HbA1c,FINS,IRI,total cholesterol,triglycerides,low-density lipoprotein,high-density lipoprotein,whole blood low shear specific viscosity,plasma specific viscosity,TM,vWF,P-selectin and MCP-1 mRNA were significantly improved compared to before treatment in both groups.After treatment,the total efficiency and TCM syndrome score in the treatment group were better than in the control group.FINS,IRI,whole blood high shear specific viscosity,plasma specific viscosity,TM,vWF,P-selectin and MCP-1 mRNA level in the treatment group were significantly reduced after treatment compared with control group.CONCLUSION:DJCs are efficacious in supplementing qi,nourishing yin and invigorating blood circulation,and upregulate MCP-1 mRNA expression in patients with T2DM subclinical vascular lesions. 展开更多
关键词 Danzhijiangtang CAPSULE Type 2 DIABETES MELLITUS SUBCLINICAL vascular lesions MONOCYTE CHEMOATTRACTANT protein-1
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High-Inclination Coring of Chang-63 of the Yanchang Formation in Huaqing Oilfield, Ordos Basin: Implications for Ancient Flow Direction and Fracture Orientation
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作者 Kun Chen Xuefeng Qü +5 位作者 Qichao Xie jian liu Jiwei Wang Youan He Dong Sun Yexiong Peng 《Engineering(科研)》 CAS 2023年第1期24-46,共23页
A promising method is to use coring of high-inclination well to find ancient flow direction and orient tiny natural fractures in massive sandstone of sandy debris flow. Determination of ancient flow direction can redu... A promising method is to use coring of high-inclination well to find ancient flow direction and orient tiny natural fractures in massive sandstone of sandy debris flow. Determination of ancient flow direction can reduce the number of exploration wells, and orientation of natural fractures is of guiding significance to the deployment of water injection development well pattern. In Block X of Huaqing Oilfield, Ordos Basin, the cores of Chang 6<sub>3</sub> section were obtained from Well Y through 16 coring operations, with a total length of 105 m. Cores is oriented through drilling parameters, the number of cores, the angle between the core edge and horizontal bedding, the coincidence degree of core profile and directional flame structure. Therefore, the micro-fractures on the core are directional. The ancient flow directions of sandy debris flow were restored by load casting, groove casting, groove casting and imbricate structure. Our results show that the ancient flow directions of sandy debris flows were southwest, southeast, northwest, and west from bottom to top. The front of the Wuqi Delta is the main source of blocky sandstone with the best oil-bearing property. Affected by the topography of the lake bottom, the sandy debris flow turned locally in the northeast direction, and the sandy debris flow from this direction was formed. The NEE-SWW-trending fractures formed in the Yanshanian period are most developed in the Huaqing area, which should be considered in deploying the flooding well network. The north-south micro-fractures formed in the Himalayan period can improve the physical properties of tight sandstone, which is of great significance for tight sandstone reservoirs. 展开更多
关键词 Core Orientation Tight Sandstone Reservoirs Sandy Debris Flow
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Algorithm for cavity flow in a new-born goaf and experimental verification 被引量:1
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作者 jian liu Qichao Zhou +2 位作者 Dong Wang Lijun Deng Ke Gao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第3期351-361,共11页
Prevention and control measures of spontaneous combustion of coal and gas accumulation in a goaf require an accurate description of its gas flow state.However,the commonly used fluid dynamics in porous media is not su... Prevention and control measures of spontaneous combustion of coal and gas accumulation in a goaf require an accurate description of its gas flow state.However,the commonly used fluid dynamics in porous media is not suitable for the new-born goaf with fracture cavity combination,multi-scale,and large blocks.In this study,we propose a cavity flow algorithm to accurately describe the gas flow state in the new-born goaf.The genetic algorithm(GA)is used to randomly generate the binary matrix of a goaf caving shape.The difference between the gas flow state calculated by the lattice Boltzmann method(LBM)and the measured data at the boundary or internal measuring points of the real goaf is taken as the GA fitness value,and the real goaf caving shape and the gas flow state are quickly addressed by GA.The experimental model of new-born goaf is established,and the laser Doppler anemometry(LDA)experiment is carried out.The results show that the Jaccard similarity coefficient between the reconstructed caving shape and the real caving shape is 0.7473,the mean square error between the calculated wind speed and the LDA-measured value is 0.0244,and the R2 coefficient is 0.8986,which verify the feasibility of the algorithm. 展开更多
关键词 Cavity flow Lattice Boltzmann method Laser Doppler anemometry New-born goaf Genetic algorithm
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Variable valence Mo^(5+)/Mo^(6+)ionic bridge in hollow spherical g-C_(3)N_(4)/Bi_(2)MoO_(6) catalysts for promoting selective visible light-driven CO_(2)photoreduction into CO 被引量:1
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作者 Wenjie He Yuechang Wei +8 位作者 Jing Xiong Zhiling Tang Yingli Wang Xiong Wang Hui Xu Xiao Zhang Xiaolin Yu Zhen Zhao jian liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期361-372,I0009,共13页
Herein,the catalysts of ultrathin g-C_(3)N_(4)surface-modified hollow spherical Bi2MoO6(g-C_(3)N_(4)/Bi2MoO6,abbreviated as CN/BMO)were fabricated by the co-solvothermal method.The variable valence Mo^(5+)/Mo^(6+)ioni... Herein,the catalysts of ultrathin g-C_(3)N_(4)surface-modified hollow spherical Bi2MoO6(g-C_(3)N_(4)/Bi2MoO6,abbreviated as CN/BMO)were fabricated by the co-solvothermal method.The variable valence Mo^(5+)/Mo^(6+)ionic bridge in CN/BMO catalysts can boost the rapid transfer of photogenerated electrons from Bi2MoO6to g-C_(3)N_(4).And the synergy effect of g-C_(3)N_(4)and Bi2MoO6components remarkably enhance CO_(2)adsorption capability.CN/BMO-2 catalyst has the best performances for visible light-driven CO_(2)reduction compared with single Bi2MoO6and g-C_(3)N_(4),i.e.,its amount and selectivity of CO product are 139.50μmol g-1and 96.88%for 9 h,respectively.Based on the results of characterizations and density functional theory calculation,the photocatalytic mechanism for CO_(2)reduction is proposed.The high-efficient separation efficiency of photogenerated electron-hole pairs,induced by variable valence Mo^(5+)/Mo^(6+)ionic bridge,can boost the rate-limiting steps(COOH*-to-CO*and CO*desorption)of selective visible light-driven CO_(2)conversion into CO.It inspires the establishment of efficient photocatalysts for CO_(2)conversion. 展开更多
关键词 g-C_(3)N_(4) Bi_(2)MoO_(6) Mo^(5+)/Mo^(6+)ionic bridge CO_(2)photoconversion CO production
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Application of silicon carbide temperature monitors in 49-2 swimming-pool test reactor 被引量:1
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作者 宁广胜 张利民 +6 位作者 钟巍华 王绳鸿 刘心语 汪定平 何安平 刘健 张长义 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期97-101,共5页
High purity SiC crystal was used as a passive monitor to measure neutron irradiation temperature in the 49-2 research reactor.The SiC monitors were irradiated with fast neutrons at elevated temperatures to 3.2×10... High purity SiC crystal was used as a passive monitor to measure neutron irradiation temperature in the 49-2 research reactor.The SiC monitors were irradiated with fast neutrons at elevated temperatures to 3.2×10^(20)n/cm^(2).The isochronal and isothermal annealing behaviors of the irradiated SiC were investigated by x-ray diffraction and four-point probe techniques.Invisible point defects and defect clusters are found to be the dominating defect types in the neutron-irradiated SiC.The amount of defect recovery in SiC reaches a maximum value after isothermal annealing for 30 min.Based on the annealing temperature dependences of both lattice swelling and material resistivity,the irradiation temperature of the SiC monitors is determined to be~410℃,which is much higher than the thermocouple temperature of 275℃ recorded during neutron irradiation.The possible reasons for the difference are carefully discussed. 展开更多
关键词 silicon carbide irradiation temperature monitor research reactor
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血栓弹力图和凝血四项在髋部骨折术后凝血功能中的相关性 被引量:1
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作者 陈敏 曾志 +1 位作者 刘建 项惠灿 《数理医药学杂志》 CAS 2023年第1期16-23,共8页
目的探究血栓弹力图(TEG)和凝血四项各参数在髋部骨折术后患者凝血功能中的相关性。方法选择2019年7月至2022年6月于我院接受人工髋关节置换术的60例患者作为研究对象,对患者围术期开展观察,记录其TEG、凝血四项、血小板(PLT)的检测结果... 目的探究血栓弹力图(TEG)和凝血四项各参数在髋部骨折术后患者凝血功能中的相关性。方法选择2019年7月至2022年6月于我院接受人工髋关节置换术的60例患者作为研究对象,对患者围术期开展观察,记录其TEG、凝血四项、血小板(PLT)的检测结果,将TEG的主要参数凝血因子激活时间(R)、血块形成速率参数(K)、弹力图最大切角(Angle角)、弹力图最大振幅(MA)与凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、纤维蛋白原(FIB)及PLT进行相关性分析,并通过绘制ROC曲线,分析TEG对人工髋关节置换术后患者凝血功能的诊断价值。结果TEG中的R值与PT值无相关性(r=0.014,P=0.488),与APTT同样无相关性(r=-0.014,P=0.467)。K值与FIB呈明显负相关性(r=-0.288,P<0.001),Angle与FIB呈明显正相关性(r=0.273,P<0.001),MA值与FIB值呈现明显正相关性(r=0.415,P<0.001)。K值与PLT呈现明显的负相关性(r=-0.164,P=0.010),Angle与PLT呈现明显的正相关(r=0.190,P=0.005),MA值与PLT呈现明显的正相关(r=0.237,P=0.002)。R、K、Angle及MA值对高凝的鉴别曲线下面积(AUC)为0.556(P=0.624)、0.923(P<0.001)、0.885(P<0.001)、0.923(P<0.001)。R、K、Angle及MA值对低凝的鉴别AUC为0.6308(P=0.361)、0.8308(P=0.021)、0.808(P=0.032)、0.7654(P=0.064)。结论人工髋关节置换术患者围手术期TEG和凝血四项指标存在一定的相关性,TEG中K、Angle及MA值对于患者的凝血状态具有较高诊断价值,可以考虑将TEG和凝血四项应用于人工髋关节置换术患者围手术期凝血状态评估中,从而为患者的血栓检测和风险评估提供参考依据。 展开更多
关键词 髋部骨折内固定 人工关节置换术 血栓弹力图 凝血四项
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Dynamical analysis,geometric control and digital hardware implementation of a complex-valued laser system with a locally active memristor
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作者 李逸群 刘坚 +2 位作者 李春彪 郝志峰 张晓彤 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期226-236,共11页
In order to make the peak and offset of the signal meet the requirements of artificial equipment,dynamical analysis and geometric control of the laser system have become indispensable.In this paper,a locally active me... In order to make the peak and offset of the signal meet the requirements of artificial equipment,dynamical analysis and geometric control of the laser system have become indispensable.In this paper,a locally active memristor with non-volatile memory is introduced into a complex-valued Lorenz laser system.By using numerical measures,complex dynamical behaviors of the memristive laser system are uncovered.It appears the alternating appearance of quasi-periodic and chaotic oscillations.The mechanism of transformation from a quasi-periodic pattern to a chaotic one is revealed from the perspective of Hamilton energy.Interestingly,initial-values-oriented extreme multi-stability patterns are found,where the coexisting attractors have the same Lyapunov exponents.In addition,the introduction of a memristor greatly improves the complexity of the laser system.Moreover,to control the amplitude and offset of the chaotic signal,two kinds of geometric control methods including amplitude control and rotation control are designed.The results show that these two geometric control methods have revised the size and position of the chaotic signal without changing the chaotic dynamics.Finally,a digital hardware device is developed and the experiment outputs agree fairly well with those of the numerical simulations. 展开更多
关键词 complex-valued chaotic systems locally active memristor multi-stability Hamilton energy geometric control
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Review on marine collagen peptides induce cancer cell apoptosis,necrosis,and autophagy by reducing oxidized free radicals
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作者 YINGHUA LUO YU ZHANG +8 位作者 TONG ZHANG YANNAN LI HUI XUE JINGLONG CAO WENSHUANG HOU jian liu YUHE CUI TING XU CHENGHAO JIN 《BIOCELL》 SCIE 2023年第5期965-975,共11页
Marine collagen peptides(MCPs)are natural products prepared by hydrolyzing marine collagen protein through a variety of chemical methods or enzymes.MCPs have a range of structures and biological activities and are wid... Marine collagen peptides(MCPs)are natural products prepared by hydrolyzing marine collagen protein through a variety of chemical methods or enzymes.MCPs have a range of structures and biological activities and are widely present in marine species.MCPs also have a small molecular weight,are easily modified,and absorbed by the body.These properties have attracted great interest from researchers studying antioxidant,anti-tumor,and anti-aging activities.MCPs of specific molecular weights have significant anti-tumor activity and no toxic side effects.Thus,MCPs have the potential use as anti-cancer adjuvant drugs.Free radicals produced by oxidation are closely related to human aging,cancer,arteriosclerosis,and other diseases,but their relationship with cancer is not well known.In this review,we focus on the antioxidant properties of MCPs in the treatment of cancer,highlighting their antioxidant molecular structure and potential for clinical practice. 展开更多
关键词 Marine Collagen Peptides(MCPs) Antioxidant ANTI-TUMOR APOPTOSIS NECROSIS AUTOPHAGY
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Delay-CJ:A novel cryptojacking covert attack method based on delayed strategy and its detection
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作者 Guangquan Xu Wenyu Dong +6 位作者 Jun Xing Wenqing Lei jian liu Lixiao Gong Meiqi Feng Xi Zheng Shaoying liu 《Digital Communications and Networks》 SCIE CSCD 2023年第5期1169-1179,共11页
Cryptojacking is a type of resource embezzlement attack,wherein an attacker secretly executes the cryptocurrency mining program in the target host to gain profits.It has been common since 2017,and in fact,it once beca... Cryptojacking is a type of resource embezzlement attack,wherein an attacker secretly executes the cryptocurrency mining program in the target host to gain profits.It has been common since 2017,and in fact,it once became the greatest threat to network security.To better prove the attack ability the harm caused by cryptojacking,this paper proposes a new covert browser-based mining attack model named Delay-CJ,this model was deployed in a simulation environment for evaluation.Based on the general framework of cryptojacking,Delay-CJ adds hybrid evasion detection techniques and applies the delayed execution strategy specifically for video websites in the prototype implementation.The results show that the existing detection methods used for testing may become invalid as result of this model.In view of this situation,to achieve a more general and robust detection scheme,we built a cryptojacking detection system named CJDetector,which is based on cryptojacking process features.Specifically,it identifies malicious mining by monitoring CPU usage and analyzing the function call information.This system not only effectively detects the attack in our example but also has universal applicability.The recognition accuracy of CJDetector reaches 99.33%.Finally,we tested the web pages in Alexa 50K websites to investigate cryptojacking activity in the real network.We found that although cryptojacking is indeed on the decline,it remains a part of network security threats that cannot be ignored. 展开更多
关键词 Cryptojacking Evasion techniques Delayed strategy Cryptocurrency mining Behavior-based detection
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Benchmark calculations and error cancelations for bond dissociation enthalpies of X-NO_(2)
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作者 jian liu Xudong He +2 位作者 Ying Xiong Fude Nie Chaoyang Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第4期144-155,共12页
Safety plays an important role in determining the applicability of energetic compounds,and the bond dissociation enthalpy(BDE)of the“trigger bond”X-NO_(2) provides useful information to evaluate various safety prope... Safety plays an important role in determining the applicability of energetic compounds,and the bond dissociation enthalpy(BDE)of the“trigger bond”X-NO_(2) provides useful information to evaluate various safety properties.Accurate and rapid calculation of the BDE of X-NO_(2) is of great significance to perform the high-throughput design of energetic compounds,which becomes an increasingly popular means of materials design.We conduct a benchmark BDE calculation for 44 X-NO_(2) samples extracted from the iBond database,with the accuracies of 55 quantum chemistry calculation levels evaluated by the experimentally measured values.Only four levels have the global mean-absolute deviation(MAD)less than 10 kJ/mol,but no calculation level can achieve that all the local MADs of each category less than 10 kJ/mol.We propose a simple correction strategy for the original calculation deviations,and apply it to 30 calculation levels screened out through a series of accuracy assessments and obtain the corrected MAD<6 kJ/mol in some cases.We define a normalized time-cost(NTC)to evaluate the time-cost of each calculation level,and confirm that PBE0-D3/6-31G^(**)(MAD=6.4 kJ/mol,NTC?0.8)works the best for most cases,followed by M062X/6-31g^(**),M062X/6-311g^(**)andɷB97XD/6-311g^(**),based on an insight into the accuracy-cost trade.The present work provides an accurate and fast solution for calculating XNO_(2) BDE via quantum chemical methods,and is expected to be beneficial to enhance the safety prediction efficiency of energetic compounds. 展开更多
关键词 Complex waveform scaling Analytical blast modeling Hopkinson-Cranz Scaled distance
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Measurement of the relative neutron sensitivity curve of a LaBr_(3)(Ce)scintillator based on the CSNS Back-n white neutron source
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作者 刘建 王东明 +3 位作者 甫跃成 李忠宝 易晗 易龙涛 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期66-72,共7页
A scintillator detector consisting of a LaBr_(3)(Ce)(0.5%)scintillator,a photomultiplier tube(PMT),and an oscilloscope were used to study the neutron sensitivities of the LaBr_(3)(Ce)scintillator at the China Spallati... A scintillator detector consisting of a LaBr_(3)(Ce)(0.5%)scintillator,a photomultiplier tube(PMT),and an oscilloscope were used to study the neutron sensitivities of the LaBr_(3)(Ce)scintillator at the China Spallation Neutron Source(CSNS)Back-n white neutron source in the double-bunch and single-bunch operation modes,respectively.Under the two operational modes,the relative neutron sensitivity curves of the LaBr_(3)(Ce)scintillator in the energy regions of 1–20 MeV and 0.5–20 MeV were obtained for the first time.In the energy range of 1–20 MeV,the two curves were nearly identical.However the relative neutron sensitivity uncertainties of the double-bunch experiment were higher than those of the single-bunch experiment.The above results indicated that the single-bunch experiment's neutron sensitivity curve has a lower minimum measurable energy than the double-bunch experiment.Above the minimum measurable energy of the double-bunch experiment,there is little difference between the measured relative neutron sensitivity curves of the single-bunch and double-bunch experiments of the LaBr_(3)(Ce)scintillator and those of other scintillators with a similar neutron response signal intensity. 展开更多
关键词 relative neutron sensitivity LaBr_(3)(Ce) China Spallation Neutron Source(CSNS) white neutron source
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