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Prompt fission neutron uranium logging(Ⅲ):logging instrument 认领 引用
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作者 Hai‑Tao Wang Yan Zhang +9 位作者 Chi Liu Jian‑Qiang Xu Li‑Jiao Zhang Zhi‑Feng Liu Xiong‑Jie Zhang Rui Chen Qi Liu Ren‑Bo Wang Shu‑Min Zhou Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第7期115-127,共13页
The domestically developed prompt fission neutron uranium logging(PFNUL)instrument for uranium exploration represents a significant advancement in China’s deep uranium mining efforts,although it has considerable chal... The domestically developed prompt fission neutron uranium logging(PFNUL)instrument for uranium exploration represents a significant advancement in China’s deep uranium mining efforts,although it has considerable challenges and complexity.This paper presents the development of a new prompt fission neutron uranium logging instrument(named UNL4)that integrates a domestic D-T neutron generator,two 3He proportional detectors,a lanthanum bromide(LaBr3)gamma-ray detector,and a digital multi-channel pulse amplitude analyzer.The near 3He detector is shielded with 1 mm of cadmium(Cd)and 5 mm of high-density polyethylene(HDPE),enabling efficient epithermal neutron detection,whereas the far 3He detector measures thermal neutrons.A LaBr3 detector is employed for gamma-ray detection,primarily originating from uranium decay.Highspeed analog-to-digital converter(ADC)and field-programmable gate array(FPGA)technologies are used to achieve rapid acquisition and transmission of both dual-energy neutron time spectra and gamma spectra.Moreover,this paper proposes a fast signal-shaping method,which reduces the dead time effect in 3He detectors on neutron time spectra.Experiments conducted in standard model boreholes with varying uranium contents demonstrated a strong linear relationship between the epithermal-to-thermal neutron ratio(E/T)and uranium content,with a fitting coefficient of R2>0.999,confirming the accuracy of the instrument.The E/T value repeatability,in both short-term(3.16%RSD)and long-term(1.2%RSD)measurements,showed excellent stability.In addition,the instrument demonstrated good performance at neutron-logging speeds of 0.3∼3 m∕min(E/T values)and gamma logging speeds of 1∼10 m∕min.Through measurements in two ore sections of the PU model with uranium contents of 87.1 ppm and 45.6 ppm showed that RD remained below approximately 10%at logging speeds of 0–2 m/s in both cases,satisfying the requirements for engineering applications.This marks the first successful development of a neutron-logging instrument for uranium exploration based on a domestic neutron generator and signifies an important contribution to uranium resource exploration. 展开更多
关键词 Uranium exploration Neutron-logging instrument Pulsed neutron Neutron time spectrum detection
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Antithymocyte globulin/antilymphocyte globulin plus kidney-nourishing Chinese Medicinal:effect on severe aplastic anemia 认领 引用 被引量：4
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作者 Xudong Tang Feng Liu +6 位作者 Liu Li Chi Liu Shanshan Zhang Haiyan Xiao Chunmei Zheng Shu Xu Rou Ma 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2012年第4期604-608,共5页
OBJECTIVE： To explore the effect of antithymocyte globulin （ATG）/antilymphocyte globulin （ALG） plus kidney-nourishing Chinese medicinal （KNCM） on se- vere aplastic anemia （SAA）. METHODS： Twenty-five subjects... OBJECTIVE： To explore the effect of antithymocyte globulin （ATG）/antilymphocyte globulin （ALG） plus kidney-nourishing Chinese medicinal （KNCM） on se- vere aplastic anemia （SAA）. METHODS： Twenty-five subjects of severe aplastic anemia were treated with ATG/ALD plus KNCM be- tween 1992 and 2009, and the clinical data before and after treatment were collected and analyzed. RESULTS： Of the 25 patients, 9 were nearly cured, 6 were improved, 5 were in remission, and 5 failed. The overall effective rate was 80.0%. The 3-year, 5-year, 10-year, 15-year survival rate were respec- tively 98.6%, 97.3%, 97.3%, 67.5%, and median sur- vival time was 180 months. Compared to the condi- tions before administering the medication of ATG/ ALG plus KNCM, after 2 weeks, reticulocyte was first improved （P=0.001）, one month later, followed by palette （P=0.037）, two months later, by neutrophil cell in peripheral blood （P=0.001）; three months lat- er, then by the hemoglobin （P=0.012）. By conduct- ing 1-year follow-up, 1 case of complication--parox-ysmal nocturnal hemoglobinuria （PNH） was identi- fied and the patient still alive today. CONCLUSION： ATG/ALG fect on SAA and could rate. plus KNCM had better ef- improve patients＇ survival 展开更多
关键词 Anemia, aplastic Reinforcing kidney Drugs, Chinese herbal Antilymphocyte serum Anti-thymocyte serum
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High entropy pyrochlore(La0.3Gd0.3Ca0.4)2(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)2O7 ceramic with amorphous-like thermal conductivity for environmental/thermal barrier coating applications 认领 引用 被引量：8
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作者 Zifan Zhao Ziyang Ruan +12 位作者 Rong Li Shixiao Yan Xiaoliang Sun Chi Liu Di Zhang Bin Xu Zhiyi Ren Meng Wang Jianyu Li Jiang Tian Yehua Jiang Jing Feng Yanchun Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2025年第2期315-326,共12页
Low thermal conductivity and excellent mechanical strength are essential to pyrochlore A2B2O7 ceramic for environmentalhermal barrier coating applications.To collaboratively tailor the mechanical and thermal propertie... Low thermal conductivity and excellent mechanical strength are essential to pyrochlore A2B2O7 ceramic for environmentalhermal barrier coating applications.To collaboratively tailor the mechanical and thermal properties of A2B2O7 ceramic,a novel high entropy pyrochlore ceramic(La0.3Gd0.3Ca0.4)2(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)2O7 with significant atomic radius and mass fluctuation is proposed by simultaneously introducing various elements with different valence states at A and B cation sites.The as-synthesized(La0.3Gd0.3Ca0.4)2(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)2O7 exhibits enhanced fracture toughness(1.68 MPa m1/2),amorphous-like low thermal conductivity(1.45 W m-1 K-1 at 900℃)and matched thermal expansion coefficient(9.0×10-6 K-1 at 1200℃)with Al2O3/Al2O3 CMCs.The extensive misfits in atomic weight,ionic radius among the substitutional cations in combination with the intrinsic oxygen vacancies in the anion sublattice play significant roles in the thermal conductivity reduction of(La0.3Gd0.3Ca0.4)2(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)2O7 ceramic.The combination of outstanding mechanical and thermal properties indicates that this type of material has a good application prospect for environmentalhermal barrier coatings. 展开更多
关键词 High entropy ceramic Pyrochlore structure Mechanical properties Thermal conductivity Phonon scattering
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Regulation of crystal and microstructures of RETaO4(RE=Nd,Sm,Gd.Ho,Er)powders synthesized via co-precipitation 认领 引用 被引量：4
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作者 Jiang Tian Lin Chen +10 位作者 Xunlei Chen Keren Luo Baihui Li Di Zhang Meng Wang Bing Xu Zhiyi Ren Shixiao Yan Xiaoliang Sun Chi Liu Jing Feng 《Journal of Rare Earths》 SCIE EI CAS CSCD 2025年第6期1246-1255,I0006,共10页
Ferroelastic rare earth tantalates(RETaO4)are widely researched as the next-generation thermal barrier coatings(TBCs),and RETaO4powders are hugely significant for synthesizing their coatings.The current research... Ferroelastic rare earth tantalates(RETaO4)are widely researched as the next-generation thermal barrier coatings(TBCs),and RETaO4powders are hugely significant for synthesizing their coatings.The current research used chemical co-precipitation within an automated experimental device to synthesize RETaO4(RE=Nd,Sm,Gd,Ho,Er)powders.The device automatically monitored and controlled the solutions'pH,improving the chemical co-precipitation efficiency.The crystal structure and microstructure of the RETaO4powders can be controlled by changing the annealing temperature,and the materials undergo an m'-m phase transition.The m'-RETaO4powders exhibit nano-size grains,while m-RETaO4powders evince micron-size grains,altered by the annealing temperatures.A simultaneous thermal analysis es-timates the reversive ferroelastic tetragonal-monoclinic phase transition temperatures.Overall,this research focuses on the synthesis,crystal structures,microstructures,and phase transition of the fabricated RETaO4powders. 展开更多
关键词 Rare earth tantalates Chemical co-precipitation method Rare earths Crystal structures Microstructures Annealingtemperatures
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Prompt fission neutron uranium logging(Ⅱ):dead-time effect of the neutron time spectrum 认领 引用 被引量：3
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作者 Yan Zhang Chi Liu +6 位作者 Shi-Liang Liu Hao-Ran Zhang Hai-Tao Wang Jin-Hui Qu Wen-Xing Hu Ren-Bo Wang Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2025年第2期82-94,共13页
The acquisition of neutron time spectrum data plays a pivotal role in the precise quantification of uranium via prompt fission neutron uranium logging(PFNUL).However,the impact of the detector dead-time effect remains... The acquisition of neutron time spectrum data plays a pivotal role in the precise quantification of uranium via prompt fission neutron uranium logging(PFNUL).However,the impact of the detector dead-time effect remains paramount in the accurate acquisition of the neutron time spectrum.Therefore,it is imperative for neutron logging instruments to establish a dead-time correction method that is not only uncomplicated but also practical and caters to various logging sites.This study has formulated an innovative equation for determining dead time and introduced a dead-time correction method for the neutron time spectrum,called the“dual flux method.”Using this approach,a logging instrument captures two neutron time spectra under disparate neutron fluxes.By carefully selecting specific“windows”on the neutron time spectrum,the dead time can be accurately ascertained.To substantiate its efficacy and discern the influencing factors,experiments were conducted utilizing a deuterium-tritium(D-T)neutron source,a Helium-3(3He)detector,and polyethylene shielding to collate and analyze the neutron time spectrum under varying neutron fluxes(at high voltages).The findings underscore that the“height”and“spacing”of the two windows are the most pivotal influencing factors.Notably,the“height”(fd)should surpass 2,and the“spacing”twd should exceed 200μs.The dead time of the 3 He detector determined in the experiment was 7.35μs.After the dead-time correction,the deviation of the decay coefficients from the theoretical values for the neutron time spectrum under varying neutron fluxes decreased from 12.4%to within 5%.Similarly,for the PFNUL instrument,the deviation in the decay coefficients decreased from 22.94 to 0.49%after correcting for the dead-time effect.These results demonstrate the exceptional efficacy of the proposed method in ensuring precise uranium quantification.The dual flux method was experimentally validated as a universal approach applicable to pulsed neutron logging instruments and holds immense significance for uranium exploration. 展开更多
关键词 PFNUL Neutron time spectrum Dead time Pulsed source Correction method
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Prompt fission neutron uranium logging(Ⅰ):direct uranium quantification method theory 认领 引用 被引量：1
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作者 Yan Zhang Chi Liu +6 位作者 Hai-Tao Wang Xiong-Jie Zhang Zhi-Feng Liu Rui Chen Jin-Hui Qu Ren-Bo Wang Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2025年第6期216-227,共12页
Prompt fission neutron uranium logging(PFNUL)is an advanced method for utilizing pulsed neutron bombardment of the ore layer and a fission reaction with uranium(235U)to detect the transient neutrons produced by fis... Prompt fission neutron uranium logging(PFNUL)is an advanced method for utilizing pulsed neutron bombardment of the ore layer and a fission reaction with uranium(235U)to detect the transient neutrons produced by fission and then directly measure and quantify uranium;however,the stability and lifetime performance of pulsed neutron sources are the key constraints to its rapid promotion.To address these problems,this study proposes a PFNUL technique for acquiring the time spectrum of dual-energy neutrons(epithermal and thermal neutrons)from the upper and lower detection structures and establishes a novel uranium quantification algorithm based on the ratio of epithermal and thermal neutron time windows(E/T)via a mathematical-physical modeling derivation.Through simulations on well-logging models with di erent uranium contents,the starting and stopping times of the time window(Δt)for uranium quantification in the dual-energy neutron time spectrum are determined to be 200 and 800μs,respectively.The minimum radius and height of the model wells are 60 and 120 cm,respectively,and the E/T values in the time window show an excellent linear relationship with the uranium content.The scale factor is KE/T=1.92 and R2=0.999,which verifies the validity of the E/T uranium quantification algorithm.In addition,experiments were carried out in the Nu series of uranium standard model wells,and the results showed that under di erent neutron source yields,the E/T-based uranium quantification method reduced the relative standard deviation of the scale factor of the uranium content from 33.41%to 1.09%,compared with a single epithermal neutron quantification method.These results prove that the E/T value uranium quantification method is una ected by the change in the neutron source yield,e ectively improves the accuracy and service life of the logging instrument,and has great scientific and popularization value. 展开更多
关键词 PFNUL Uranium exploration Pulsed neutrons Neutron time spectrum
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Effect of ωiso and α precipitation during aging on tensile properties and impact toughness of a metastable β type Ti alloy 认领 引用
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作者 Yan-fei Xu Lv-ming Chen +10 位作者 Chi Liu Can Zhou Sha Zhang Jun-zhao Li Zhi-ming Guo Han-qing Xiong Jian Liu Long Liu Jian Li Zhuo Fu Guang-sheng Zeng 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2025年第7期2172-2182,共11页
The effect ofωiso andαprecipitation on microstructure,microhardness,tensile properties and impact toughness of Ti-25Nb-10Ta-1Zr-0.2Fe(TNTZF)alloy was investigated.The results showed that the solution treated TNTZF a... The effect ofωiso andαprecipitation on microstructure,microhardness,tensile properties and impact toughness of Ti-25Nb-10Ta-1Zr-0.2Fe(TNTZF)alloy was investigated.The results showed that the solution treated TNTZF alloy with a small amount of nano-sizedωath particles inβmatrix possesses tensile strength of 697 MPa,elongation of~34%,Young’s modulus(YM)of 75 GPa,and impact toughness of 58.7 J/cm2.After aging at relatively lower temperatures of 400℃,the hardness and modulus of the alloy increased significantly,while the plasticity and toughness dropped sharply due to the precipitation ofωiso phase.ωiso phase displayed an ellipsoidal morphology with high volume fraction and a size of about 50 nm after aging at 400℃,leading to the highest hardness of 364 HV and YM of 108 GPa,along with completely embrittlement since elongation and toughness were almost zero.A brittle impact fracture morphology was observed in the alloy,which is dominated by intergranular fracture,with a mixed fracture characteristics of cleavage surfaces,terraces and tiny dimples.When aged at 550℃,plate-likeαdistributed inβmatrix uniformly and inβgrain boundaries in parallel,resulting in the high strength of 804 MPa,as well as lowest YM of 72 GPa,elongation of 9%and toughness of 35.8 J/cm2.The fracture morphology of the alloy aged at 550℃showed a ductile fracture mechanism with a large number of dimples. 展开更多
关键词 β-Ti alloy Aging precipitation Microstructure Tensile property Impact toughness
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In-situ growth of metal organic framework on hollow graphene foam for high-efficiency microwave absorption 认领 引用 被引量：2
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作者 Qiang-Qiang Zhao Tian-Yu Zhang +7 位作者 Chaoqun Ma Ibrar Ahmed Han Wang Bo Sun Chi Liu Chang Liu Hui-Ming Cheng You Zeng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2025年第32期251-260,共10页
The demand for lightweight,thin,and broadband microwave absorption materials has been grow-ing rapidly with advancements in microelectronics and aerospace technology.Conventional microwave-absorbing materials often su... The demand for lightweight,thin,and broadband microwave absorption materials has been grow-ing rapidly with advancements in microelectronics and aerospace technology.Conventional microwave-absorbing materials often suffer from poor dispersion and limited electromagnetic attenuation capac-ity.Herein,we report a novel microwave absorption material that integrates ZIF-67-derived metal or-ganic frameworks(MOFs)with hollow graphene foams(GrFs)synthesized via chemical vapor deposition.The hollow GrFs act as resonant cavities in enhancing multiple reflections and conductive loss,while the MOFs optimize impedance matching for highly efficient microwave absorption.The MOF@GrF-filled paraffin composites achieve a minimum reflection loss(RLmin)of-50.2 dB at a thickness of 1.3 mm and 7.1 wt.%filler loading,with an impressive microwave absorption efficiency of-38.6 dB/mm.This superior performance is attributed to the synergistic interactions between GrFs and MOFs,integrating conductive loss,cavity confinement,dipole polarization,interfacial polarization,magnetic loss,and im-proved impedance matching.This study paves a way for fabricating high-efficiency microwave absorption materials for application in fields of aerospace,medical equipment,and electronic industry. 展开更多
关键词 Hollow graphene foam Metal organic frameworks Cavity confinement In-situ growth Microwave absorption
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Economic outcomes of AI-based diabetic retinopathy screening:a systematic review and meta-analysis 认领 引用
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作者 Yue Wu Yueye Wang +5 位作者 Jian Zhang Yanxian Chen Keyao Zhou Chi Liu Xiaotong Han Mingguang He 《Eye Science》 2025年第2期121-135,共15页
Objective:Diabetic retinopathy(DR)is a top leading cause of blindness worldwide,requiring early detection for timely intervention.Artificial intelligence(AI)has emerged as a promising tool to improve DR screening effi... Objective:Diabetic retinopathy(DR)is a top leading cause of blindness worldwide,requiring early detection for timely intervention.Artificial intelligence(AI)has emerged as a promising tool to improve DR screening efficiency,accessibility,and cost-effectiveness.This study conducted a systematic review of literature and meta-analysis on the economic outcomes of AI-based DR screening.Methods:A systematic review of studies published before September 2024 was conducted throughout PubMed,Scopus,Embase,the Cochrane Library,the National Health Service Economic Evaluation Database,and the Cost-Effectiveness Analysis Registry.Eligible studies were included if they were(1)conducted among type 1 diabetes mellitus or type 2 diabetes mellitus adult diabetic population;(2)studies compared AI-based DR screening strategy to non-AI screening;and(3)performed a cost-effectiveness analysis.Meta-analysis was applied to pool incremental net benefit(INB)across studies stratified by country income and study perspective using a random-effects model.Statistical heterogeneity among studies was assessed using the I2 statistic,Cochrane Q statistics,and meta regression.Results:Nine studies were included in the analysis.From a healthcare system/payer perspective,AI-based DR screening was significantly cost-effective compared to non-AI-based screening,with a pooled INB of 615.77(95%confidence interval[CI]:558.27-673.27).Subgroup analysis showed robust cost-effectiveness of AI-based DR screening in high-income countries(INB=613.62,95%CI:556.06-671.18)and upper-/lower-middle income countries(INB=1,739.97,95%CI:423.13-3,056.82)with low heterogeneity.From a societal perspective,AI-based DR screening was generally cost-effective(INB=5,102.33,95%CI:-815.47-11,020.13),though the result lacked statistical significance and showed high heterogeneity.Conclusions:AI-based DR screening is generally cost-effective from a healthcare system perspective,particularly in high-income countries.Heterogeneity in cost-effectiveness across different perspectives highlights the importance of context-specific evaluations,to accurately evaluate the potential of AI-based DR screening in reducing global healthcare disparities. 展开更多
关键词 economic evaluation incremental net benefit meta-analysis artificial intelligence diabetic retinopathy
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A decade of progress in artificial intelligence for fundus image-based diabetic retinopathy screening(2014-2024):a bibliometric analysis 认领 引用
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作者 Yuting Huang Yunfei Qi +7 位作者 Chi Liu Fengshi Jing Changjin Li Minghao Wang Congcong Zhu Peng Gui Zongyuan Ge Xiaotong Han 《Eye Science》 2025年第2期188-201,共14页
Objective:Diabetic retinopathy(DR)screening using artificial intelligence(AI)has evolved significantly over the past decade.This study aimed to analyze research trends,developments,and patterns in AI-based fundus imag... Objective:Diabetic retinopathy(DR)screening using artificial intelligence(AI)has evolved significantly over the past decade.This study aimed to analyze research trends,developments,and patterns in AI-based fundus image DR screening from 2014 to 2024 through bibliometric analysis.Methods:The study used CiteSpace and Microsoft Excel to analyze 1,172 publications from the Web of Science Core Collection database.The analysis included publication trends over time,citation patterns,institutional collaborations,and the emergence of keywords.Results:From 2014-2022,there was a steady increase in the number of publications,reaching a peak in 2021.India(26%),China(20.05%),and the USA(9.98%)were the major contributors to research output in this field.Among the publication venues,IEEE ACCESS stood out as the leading one,with 44 articles published.The research landscape has evolved from traditional image processing techniques to deep learning approaches.In recent years,there has been a growing emphasis on multimodal AI models.The analysis identified three distinct phases in the development of AI-based DR screening:CNN-based systems(2014-2020),Vision Transformers and innovative learning paradigms(2020-2022),and large foundation models(2022-2024).Conclusions:The field has demonstrated a mature development in traditional AI approaches and is currently in the process of transitioning toward multimodal learning technologies.Future directions suggest an increased focus on the integration of telemedicine,innovative AI algorithms,and real-world implementation of these technologies in real-world settings. 展开更多
关键词 artificial intelligence fundus image diabetic retinopathy bibliometric
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CFD analysis of a transfer matrix of exhaust muffler with mean flow and prediction of exhaust noise 认领 引用 被引量：11
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作者 Lian-yun LIU Zhi-yong HAO Chi LIU 《Journal of Zhejiang University-SCIENCE A》 SCIE EI CAS CSCD 2012年第9期709-716,共8页
A multi-dimensional computational fluid dynamics(CFD) approach was proposed in this study aiming to calculate the transfer matrix of an engine exhaust muffler in the conditions with and without mean flow.The CFD model... A multi-dimensional computational fluid dynamics(CFD) approach was proposed in this study aiming to calculate the transfer matrix of an engine exhaust muffler in the conditions with and without mean flow.The CFD model of the muffler with absorptive material defined as porous zone was calibrated with the measured noise reduction without mean flow,and was further employed to study the effect of the mean flow on the acoustic performance of the muffler.Furthermore,the exhaust acoustical source was derived from the calculated transfer matrices of six different additional acoustic loads obtained by the proposed CFD approach as well as the measured tail noise based on a multiload least squares method.Finally,the exhaust noise was predicted based on Thevenin's theorem.The proposed CFD approach was suggested to be able to predict the acoustic performance of a complex muffler considering mean flow(without and with mean flow) and heat transfer,and provide reasonable results of the exhaust noise. 展开更多
关键词 Computational fluid dynamics （CFD） Transfer matrix Mean flow Acoustical source Exhaust noise
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Three-Dimensional Collapse Analysis for a Shallow Cavity in Layered Strata Based on Upper Bound Theorem 认领 引用 被引量：2
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作者 Hongtao Wang Ping Liu +3 位作者 Lige Wang Chi Liu Xin Zhang Luyao Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第7期375-391,共17页
Layered rock strata are observed to be common during the excavation of tunnels or cavities,and may significantly affect the deformation and failure characteristics of surrounding rock masses due to various complex for... Layered rock strata are observed to be common during the excavation of tunnels or cavities,and may significantly affect the deformation and failure characteristics of surrounding rock masses due to various complex forms and mechanical properties.In this paper,we propose a three-dimensional axisymmetric velocity field for roof collapse of shallow cavities in multi rock layers,by considering the influences of roof cross-section shapes,supporting pressure,ground overload,etc.The internal energy dissipation rate and work rates of external forces corresponding to the velocity field are computed by employing the Hoek-Brown strength criterion and its associated flow rule.Further,the equations of the collapse surfaces and the corresponding weight of collapsing rock masses are derived on the basis of upper bound theorem.Furthermore,we validate the proposed method by comparing the results of numerical calculations and existing research findings.The change laws of the collapse range under varying parameters are obtained for the presence of rectangular and spherical cavities.We also find that the three-dimensional mechanism is relatively safer for engineering designing actually,compared with the traditional two-dimensional mechanism.All these conclusions may provide workable guidelines for the support design of shallow cavities in layered rock strata practically. 展开更多
关键词 Shallow cavity three-dimensional collapse layered rock strata upper
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凝结相中功能性碳材料和碳纳米复合物催化转化生物质制备可再生化学品(英文) 认领 引用 被引量：1
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作者 John Matthiesen Thomas Hoff +3 位作者 Chi Liu Charles Pueschel Radhika Rao Jean-Philippe Tessonnier 《催化学报》 2014年第6期842-855,共14页
The production of chemicals from lignocellulosic biomass provides opportunities to synthesize chemicals with new functionalities and grow a more sustainable chemical industry. However, new challenges emerge as researc... The production of chemicals from lignocellulosic biomass provides opportunities to synthesize chemicals with new functionalities and grow a more sustainable chemical industry. However, new challenges emerge as research transitions from petrochemistry to biorenewable chemistry. Compared to petrochemisty, the selective conversion of biomass-derived carbohydrates requires most catalytic reactions to take place at low temperatures (< 300 °C) and in the condensed phase to prevent reactants and products from degrading. The stability of heterogeneous catalysts in liquid water above the normal boiling point represents one of the major challenges to overcome. Herein, we review some of the latest advances in the field with an emphasis on the role of carbon materials and carbon nanohybrids in addressing this challenge. 展开更多
关键词 生物质转化 碳水化合物 纳米复合物 催化反应 化学物 可再生 凝聚相 功能化学品
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Effect of Ni-P content on microstructure and mechanical properties of Fe-Ni-P alloy 认领 引用
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作者 Chi Liu Yu-xuan Liu +5 位作者 Ji-ping Lu Yan-huan Wang Lin-wang Chen Cheng-song Zhang Da-zhi Chen Guo-dong Cui 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2022年第11期1846-1852,共7页
A series of Fe-Ni-P alloys with different Ni-P contents were prepared by micro-press sintering,and the influence of the contents on the final microstructure and mechanical properties was evaluated.Sample Fe-34(Ni,P)co... A series of Fe-Ni-P alloys with different Ni-P contents were prepared by micro-press sintering,and the influence of the contents on the final microstructure and mechanical properties was evaluated.Sample Fe-34(Ni,P)contains the highest Ni-P content(34.18 wt.%)and its relative density reaches 98.75%,which is attributed to the introduction of an appropriate amount of liquid phase during the sintering process.The main phase of the sample is transformed from a to c phase under the gradual increment of Ni-P content.Simultaneously,a large number of phosphides that have strong inhibition on the migration and expansion of grain boundaries are precipitated on the matrix,and synergistic effect with low-temperature sintering results in partial grain refinement.The samples with high Ni-P content have a high volume of c phase,which makes the sample show the optimal plasticity under the maximum compressive load.And the fracture mode has also changed from brittle fracture to a mixed mode of brittle and ductile fracture.The decrease in the proportion of a phase has a weakening effect on the strength,but the refinement of the grain and the increase in the phosphide are the factors that increase the strength,so that the degree of manifestation varies in different Ni-P levels. 展开更多
关键词 Fe-Ni-P alloy Liquid phase sintering Mechanical behavior Microstructure
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A silicon-graphene-silicon transistor with an improved current gain 认领 引用
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作者 Chi Liu Xu-Qi Yang +4 位作者 Wei Ma Xin-Zhe Wang Hai-Yan Jiang Wen-Cai Ren Dong-Ming Sun 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第9期127-130,共4页
In history,semiconductor-metal-semiconductor transistor(SMST)was proposed for frequency improvement.However,a general fabrication method is still missing due to the unsolved technological problem of deposition of a ge... In history,semiconductor-metal-semiconductor transistor(SMST)was proposed for frequency improvement.However,a general fabrication method is still missing due to the unsolved technological problem of deposition of a general crystalline semiconductor on metal,and a thinner metal base is also difficult to be fabricated with high quality.Recently,due to the atomic thickness of graphene,the concept of semiconductor-graphene-semiconductor transistor(SGST)has emerged which leads to the renaissance of SMST,however the experimental study is in its infancy.In this letter,SMST and SGST are fabricated using Si membrane transfer.It is found the common base current gain can be improved from about 0.5%in a Si-Au-Si transistor to about 1%in a Si-Gr-Ge one,and to above 10%in a Si-Gr-Si one,which is attributed to both the ultra-thin thickness and the quantum capacitance effect of graphene. 展开更多
关键词 Semiconductor metal semiconductor transistor Graphene base transistor Graphene base heterojunction transistor
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Bioinspired phototransistor with tunable sensitivity for low-contrast target detection 认领 引用
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作者 Ruyue Han Dayu Jia +7 位作者 Bo Li Shun Feng Guoteng Zhang Yun Sun Zheng Han Chi Liu Hui-Ming Cheng Dong-Ming Sun 《Light: Science & Applications》 SCIE EI CAS CSCD 2026年第1期130-139,共10页
Accurate recognition of low-contrast targets in complex visual environments is essential for advanced intelligent machine vision systems.Conventional photodetectors often suffer from a weak photoresponse and a linear ... Accurate recognition of low-contrast targets in complex visual environments is essential for advanced intelligent machine vision systems.Conventional photodetectors often suffer from a weak photoresponse and a linear dependence of photocurrent on light intensity,which restricts their ability to capture low-contrast features and makes them susceptible to noise.Inspired by the adaptive mechanisms of the human visual system,we present a molybdenum disulfide(MoS2)phototransistor with tunable sensitivity,in which the gate stack incorporates a heterostructure diode—composed of O-plasma-treated MoS2 and pristine MoS2—that serves as the photosensitive layer.This configuration enables light-intensity-dependent modulation of the diode’s conductance,which dynamically in turn alters the voltage distribution across the gate dielectric and transistor channel,leading to a significant photoresponse.By modulating the gate voltage,the light response range can be finely tuned,maintaining high sensitivity to low-contrast targets while suppressing noise interference.Compared to conventional photodetectors,the proposed device achieves a 1000-fold improvement in sensitivity for low-contrast signal detection and exhibits significantly enhanced noise immunity.The intelligent machine vision system built on this device demonstrates exceptional performance in detecting low-contrast targets,underscoring its promise for next-generation machine vision applications. 展开更多
关键词 tunable sensitivity adaptive mechanisms noise immunity advanced intelligent machine vision systemsconventional photodetectors bioinspired phototransistor machine vision human visual systemwe low contrast target detection
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Cathepsin C orchestrates RSV-induced asthma exacerbation through the dual effect of monocyte-derived macrophages 认领 引用
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作者 Xizi Du Xinyu Wu +13 位作者 Lin Yuan Huaiqing Luo Leyuan Wang Huijun Liu Ye Yao Siqi Yao Qiuyan Qin Qianyu Zhao Dan Liu Yang Xiang Xiaoqun Qin Ming Yang Weining Xiong Chi Liu 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2026年第6期719-733,共15页
Asthma exacerbations(AEs),especially those triggered by respiratory syncytial virus(RSV),remain clinically intractable because of limited treatment options and significant immune heterogeneity.In this study,we investi... Asthma exacerbations(AEs),especially those triggered by respiratory syncytial virus(RSV),remain clinically intractable because of limited treatment options and significant immune heterogeneity.In this study,we investigated the central cellular and molecular mechanisms driving RSV-induced AEs using a house dust mite-sensitized mouse model.Through macrophage depletion,transcriptomic profiling,and pathway inhibition,we identified monocyte-derived macrophages(Mo-Mφs)as key orchestrators of both antiviral responses and inflammatory amplification.Mechanistically,Mo-Mφs upregulate and secrete cathepsin C(CTSC),which in turn activates a previously unrecognized PR3/p38/RELB signaling axis.This axis established a positive feedback loop,sustaining macrophage activation and pathogenic inflammation.Pharmacological inhibition of CTSC disrupted this loop,leading to reduced lung inflammation,mucus hypersecretion,and airway hyperresponsiveness.However,this intervention was accompanied by a measurable compromise in antiviral immunity.This study reveals a previously unrecognized CTSC-driven positive feedback loop in Mo-Mφs as a core pathogenic mechanism underlying RSV-induced AE.These findings identify CTSC as a promising mechanism-based therapeutic target,highlighting the need to carefully balance inflammation control against the preservation of antiviral immunity. 展开更多
关键词 asthma exacerbation monocyte-derived macrophages CTSC RSV
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抗VEGF联合复合式小梁切除术治疗新生血管性青光眼 认领 引用 被引量：12
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作者 孙曹毓 刘驰 +1 位作者 周晶 王辉 《国际眼科杂志》 CAS 北大核心 2020年第9期1583-1586,共4页
目的:探讨抗VEGF联合复合式小梁切除术治疗新生血管性青光眼的临床疗效。方法:选取2017-01/2019-06就诊于沈阳市第四人民医院并入院治疗的符合研究条件的新生血管性青光眼患者42例43眼。患者入组后行血常规、尿常规、心电图、视力、眼... 目的:探讨抗VEGF联合复合式小梁切除术治疗新生血管性青光眼的临床疗效。方法:选取2017-01/2019-06就诊于沈阳市第四人民医院并入院治疗的符合研究条件的新生血管性青光眼患者42例43眼。患者入组后行血常规、尿常规、心电图、视力、眼压、眼前节照相,根据屈光间质状态完善眼底检查。根据入院眼压情况予全身及局部联合降眼压治疗,术前抗生素滴眼。入院第3d患者术眼行抗VEGF治疗,根据患者自主选择予玻璃体腔注射雷珠单抗或康柏西普,分为雷珠单抗组和康柏西普组;注药72h后行复合式小梁切除术(结膜下及巩膜瓣局部应用氟尿嘧啶浸润+可调节缝线+房角分离)。术后随访6mo(1d,1、2wk,1、2、3、6mo),比较两组新生血管消退情况、视力、眼压。结果:康柏西普眼内注射液和雷珠单抗眼内注射液均可有效消退虹膜新生血管,治疗新生血管性青光眼疗效无差别。术后1d,1、2wk,1、2、3、6mo大部分患者眼压均明显下降,部分患者视力提高。结论:抗VEGF联合复合式小梁切除术可有效控制新生血管性青光眼眼压,部分患者可提高视力,提升患者生活质量。 展开更多
关键词 新生血管性青光眼 小梁切除术 VEGF
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可自动校准距离的智能手机视力测试APP(WHOeyes)的真实世界应用 认领 引用
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作者 吴怡 Stuart Keel +6 位作者 Vera Lúcia A lves Ca rneiro 张释然 王伟 刘驰 汤璇璋 韩晓彤 何明光 《眼科学报》 CAS 2024年第9期431-442,共12页
目的:开发一款可自动校准测试距离的智能手机视力检测APP(WHOeye的iOS版本),并评估其实用性。方法:WHOeyes在经过验证的视力检测APP“V@home”的基础上新增自动距离校准(automatic distance calibration,ADC)功能。研究招募了3组不同年... 目的:开发一款可自动校准测试距离的智能手机视力检测APP(WHOeye的iOS版本),并评估其实用性。方法:WHOeyes在经过验证的视力检测APP“V@home”的基础上新增自动距离校准(automatic distance calibration,ADC)功能。研究招募了3组不同年龄(≤20岁、20~40岁、>40岁)的中国受试者,分别使用糖尿病视网膜病变早期治疗研究(Early Treatment Diabetic Retinopathy Study,ETDRS)视力表和WHOeyes进行远距离和近距离的视力检测。ADC功能用于确定WHOeyes的测试距离。红外测距仪用于确定ETDRS的测试距离以及WHOeyes的实际测试距离。通过问卷调查评估用户满意度。结果:WHOeyes ADC确定的实际测试距离在3个年龄组中均与预期测试距离总体上表现出良好的一致性(P>0.50)。在远距离和近距离视力检测方面,WHOeyes的准确性与ETDRS相当。WHOeyes与ETDRS之间的平均视力差异范围为–0.084~0.012 logMAR,各组的二次加权卡帕系数(quadratic weighted kappa,QWK)均大于0.75。WHOeyes在近距离和远距离视力检测中的重测信度高,平均差异范围为–0.040~0.004 logMAR,QWK均大于0.85。问卷调查显示WHOeyes具有较好的用户体验和接受度。结论:与金标准ETDRS视力表方法相比,WHOeyes测试距离较为准确,可以提供准确的远距离和近距离视力测量结果。 展开更多
关键词 智能手机 视力检查 WHOeyes V@home ETDRS
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Intelligent design of multifunctional graphene-based aerogels for ultra-broadband microwave absorption 认领 引用 被引量：1
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作者 Xiaohan Wang Ye Yuan +4 位作者 Leyao Wang Xianxian Sun Tieliang Zhang Chi Liu Yibin Li 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2025年第12期89-99,共11页
The growing demand for microwave absorbing materials to mitigate electromagnetic pollution has driven the exploration of efficient design strategies.However,traditional experimental approaches for optimizing multicomp... The growing demand for microwave absorbing materials to mitigate electromagnetic pollution has driven the exploration of efficient design strategies.However,traditional experimental approaches for optimizing multicomponent and multilayer structures are time-consuming.To rapidly predict and optimize the electromagnetic parameters of microwave absorbing materials,a machine learning-assisted design framework has been proposed.A series of graphene/SiO2(GS)and graphene/BaTiO3(GB)aerogels were prepared by electrospinning technology,and their electromagnetic parameter datasets were used to train a machine learning model.The model achieved a maximum prediction accuracy of 97.3%,significantly accelerating the design process.By integrating the predicted parameters into simulation software,gradient impedance structures were rapidly designed,yielding multifunctional aerogels with an ultrawideband absorption range of 3.26–17.30 GHz at a thickness of 20 mm.Compared with conventional methods,this machine learning strategy reduces the research cycle to mere weeks,enabling the fast and efficient design of high-performance absorbing materials.Additionally,the aerogel demonstrated excellent thermal insulation and soundproofing capabilities,underscoring its multifunctionality.This study demonstrates the potential of machine learning in accelerating the development of next-generation microwave absorbing materials. 展开更多
关键词 microwave absorbing materials machine learning multifunction research cycle efficient design
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