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Temperature dependence of mechanical properties and damage evolution of hot dry rocks under rapid cooling
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作者 Longjun Dong Yihan Zhang +2 位作者 Lichang wang lu wang Shen Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期645-660,共16页
Understanding the differences in mechanical properties and damage characteristics of granitoid under high temperatures is crucial for exploring deep geothermal resources.This study analyzes the evolution of the acoust... Understanding the differences in mechanical properties and damage characteristics of granitoid under high temperatures is crucial for exploring deep geothermal resources.This study analyzes the evolution of the acoustic emission(AE)characteristics and mechanical parameters of granodiorite and granite after heating and water cooling by uniaxial compression and variable-angle shear tests under different temperature gradients.We identify their changes in mesostructure and mineral composition with electron probe microanalysis and scanning electron microscopy.Results show that these two hot dry rocks have similar diagenetic minerals and microstructure,but show significantly different mechanical and acoustic characteristics,and even opposing evolution trends in a certain temperature range.At the temperatures ranging from 100℃to 500℃,the compressive and shear mechanical properties of granodiorite switch repeatedly between weakening and strengthening,and those of granite show a continuous weakening trend.At 600℃,both rocks exhibit a deterioration of mechanical properties.The damage mode of granite is characterized by initiating at low stress,exponential evolutionary activity,and intensified energy release.In contrast,granodiorite exhibits the characteristics of initiating at high stress,volatile evolutionary activity,and intermittent energy release,due to its more stable microstructure and fewer thermal defects compared to granite.As the temperature increases,the initiation and propagation of secondary cracks in granodiorite are suppressed to a certain extent,and the seismicity and brittleness are enhanced.The subtle differences in grain size,microscopic heterogeneity,and mineral composition of the two hot dry rocks determine the different acoustic-mechanical characteristics under heating and cooling,and the evolution trends with temperature.These findings are of great significance for the scientific and efficient construction of rock mass engineering by rationally utilizing different rock strata properties. 展开更多
关键词 Hot dry rock Acoustic emission Mechanical properties High temperature DAMAGE
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Latest developments in EUV photoresist evaluation capability at Shanghai Synchrotron Radiation Facility
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作者 Zhen‑Jiang Li Cheng‑Hang Qi +8 位作者 Bei‑Ning Li Shu‑Min Yang Jun Zhao Zhi‑Di Lei Shi‑Jie Zhu Hao Shi lu wang Yan‑Qing Wu Ren‑Zhong Tai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期206-215,共10页
Evaluating the comprehensive characteristics of extreme ultraviolet(EUV)photoresists is crucial for their application in EUV lithography,a key process in modern technology.This paper highlights the capabilities of the... Evaluating the comprehensive characteristics of extreme ultraviolet(EUV)photoresists is crucial for their application in EUV lithography,a key process in modern technology.This paper highlights the capabilities of the Shanghai Synchrotron Radiation Facility(SSRF)08U1B beamline in advancing this field.Specifically,it demonstrates how this beamline can create fringe patterns with a 15-nm half-pitch on a resist using synchrotron-based EUV lithography.This achievement is vital for evaluating EUV photoresists at the advanced 5-nm node.We provide a detailed introduction to the methods and experimental setup used at the SSRF 08U1B beamline to assess an EUV photoresist.A significant part of this research involved the fabrication of high-resolution hydrogen silsesquioxane mask gratings.These gratings,with an aspect ratio of approximately 3,were created using electron beam lithography on an innovative mask framework.This framework was crucial in eliminating the impact of zeroth-order light on interference patterns.The proposed framework propose offers a new approach to mask fabrication,particularly beneficial for achromatic Talbot lithography and multicoherent-beam interference applications. 展开更多
关键词 Extreme ultraviolet photoresist Interference lithography HIGH-RESOLUTION Electron beam lithography·Hydrogen silsesquioxane GRATING
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Occult pancreaticobiliary reflux is a pathogenic factor of some benign biliary diseases and gallbladder cancer
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作者 lu wang Zhi-Wei Zhang +3 位作者 Tong Guo Peng Xie Xiao-Rui Huang Ya-Hong Yu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第3期288-293,共6页
Background:Pancreaticobiliary maljunction(PBM)is a well-known high-risk factor for biliary malignant tumors because of constant pancreaticobiliary reflux(PBR).However,the impact of occult pancreaticobiliary reflux(OPR... Background:Pancreaticobiliary maljunction(PBM)is a well-known high-risk factor for biliary malignant tumors because of constant pancreaticobiliary reflux(PBR).However,the impact of occult pancreaticobiliary reflux(OPR),which is characterized by high bile amylase levels in individuals with anatomically normal pancreaticobiliary junction,on biliary diseases remains unclear.The aim of this study was to assess the correlation between OPR and biliary diseases.Methods:We enrolled 94 consecutive patients with normal pancreaticobiliary junction and primary biliary diseases confirmed by magnetic resonance cholangiopancreatography.We prospectively collected patients’bile samples and measured bile amylase levels.We investigated the incidence of OPR and the difference in bile amylase levels among these patients and assessed the correlation between high bile amylase levels(HBAL)and benign or malignant biliary diseases,as well as the OPR risk factors.Results:The incidence of OPR was 36.6%in patients with benign biliary diseases,26.7%in those with cholangiocarcinoma and 62.5%in those with gallbladder cancer.The median bile amylase level tended to be higher in patients with gallbladder cancer than in those with benign biliary diseases,but there was no significant difference(165.5 IU/L vs.23.0 IU/L,P=0.212).The prevalence of an HBAL with bile amylase levels of 1000-7500 IU/L was similar in patients with gallbladder cancer and benign biliary diseases.However,the incidence of HBAL with bile amylase levels greater than 7500 IU/L was significantly higher in patients with gallbladder cancer than in those with benign biliary diseases(37.5%vs.4.2%,P=0.012).Multivariate logistic regression analysis revealed that choledocholithiasis was an independent risk factor for OPR.Conclusions:OPR can occur in benign and malignant biliary diseases,and it may be a pathogenic factor for some benign biliary diseases and a high-risk factor for gallbladder cancer.There is a correlation between choledocholithiasis and OPR. 展开更多
关键词 Occult pancreaticobiliary reflux Biliary diseases Bile amylase Pancreaticobiliary junction Gallbladder cancer
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Value and prognostic factors of repeat hepatectomy for recurrent colorectal liver metastasis
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作者 Jia-Min Zhou lu wang An-Rong Mao 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2023年第6期570-576,共7页
Background:More than 50%of patients with colorectal cancer develop liver metastases.Hepatectomy is the preferred treatment for resectable liver metastases.This review provides a perspective on the utility and relevant... Background:More than 50%of patients with colorectal cancer develop liver metastases.Hepatectomy is the preferred treatment for resectable liver metastases.This review provides a perspective on the utility and relevant prognostic factors of repeat hepatectomy in recurrent colorectal liver metastasis(CRLM).Data sources:The keywords“recurrent colorectal liver metastases”,“recurrent hepatic metastases from colorectal cancer”,“liver metastases of colorectal cancer”,“repeat hepatectomy”,“repeat hepatic resec-tion”,“second hepatic resection”,and“prognostic factors”were used to retrieve articles published in the PubMed database up to August 2020.Additional articles were identified by a manual search of references from key articles.Results:Despite improvements in surgical methods and perioperative chemotherapy,recurrence remains common in 37%-68%of patients.Standards or guidelines for the treatment of recurrent liver metastases are lacking.Repeat hepatectomy appears to be the best option for patients with resectable metastases.The commonly reported prognostic factors after repeat hepatectomy were R0 resection,carcinoembryonic antigen level,the presence of extrahepatic disease,a short disease-free interval between initial and repeat hepatectomy,the number(>1)and size(≥5 cm)of hepatic lesions,requiring blood transfusion,and no adjuvant chemotherapy after initial hepatectomy.The median overall survival after repeat hepatectomy ranged from 19.3 to 62 months,and the 5-year overall survival ranged from 21%to 73%.Chemotherapy can act as a test for the biological behavior of tumors with the goal of avoiding unnecessary surgery,and a multimodal approach involving aggressive chemotherapy and repeat hepatectomy might be the treatment of choice for patients with early recurrent CRLM.Conclusions:Repeat hepatectomy is a relatively safe and effective treatment for resectable recurrent CRLM.The presence or absence of prognostic factors might facilitate patient selection to improve short-and long-term outcomes. 展开更多
关键词 HEPATECTOMY Colorectal neoplasms Liver neoplasms Neoplasm recurrence PROGNOSIS
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Breath-by-breath measurement of exhaled ammonia by acetonemodifier positive photoionization ion mobility spectrometry via online dilution and purging sampling
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作者 lu wang Dandan Jiang +7 位作者 Lei Hua Chuang Chen Dongming Li Weiguo wang Yiqian Xu Qimu Yang Haiyang Li Song Leng 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第4期412-420,共9页
Exhaled ammonia(NH_(3))is an essential noninvasive biomarker for disease diagnosis.In this study,an acetone-modifier positive photoionization ion mobility spectrometry(AM-PIMS)method was developed for accurate qualita... Exhaled ammonia(NH_(3))is an essential noninvasive biomarker for disease diagnosis.In this study,an acetone-modifier positive photoionization ion mobility spectrometry(AM-PIMS)method was developed for accurate qualitative and quantitative analysis of exhaled NH_(3)with high selectivity and sensitivity.Acetone was introduced into the drift tube along with the drift gas as a modifier,and the characteristic NH_(3)product ion peak of(C_(3)H_(6)O)_(4)NH_(4)^(+)(K_(0)=1.45 cm^(2)/V·s)was obtained through the ion-molecule reaction with acetone reactant ions(C_(3)H_(6)O)_(2)H^(+)(K_(0)=1.87 cm^(2)/V·s),which significantly increased the peak-to-peak resolution and improved the accuracy of exhaled NH_(3)qualitative identification.Moreover,the interference of high humidity and the memory effect of NH_(3)molecules were significantly reduced via online dilution and purging sampling,thus realizing breath-by-breath measurement.As a result,a wide quantitative range of 5.87-140.92μmol/L with a response time of 40 ms was achieved,and the exhaled NH_(3)profile could be synchronized with the concentration curve of exhaled CO_(2).Finally,the analytical capacity of AM-PIMS was demonstrated by measuring the exhaled NH_(3)of healthy subjects,demonstrating its great potential for clinical disease diagnosis. 展开更多
关键词 Photoionization ion mobility spectrometry Acetone modifier Exhaled ammonia Breath analysis
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Practical evaluation of prelithiation strategies for next-generation lithium-ion batteries
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作者 Shiming Chen Zhen wang +6 位作者 Meng Zhang Xiaoze Shi lu wang Weifeng An Zikun Li Feng Pan luyi Yang 《Carbon Energy》 SCIE CSCD 2023年第8期55-77,共23页
With the increasing market demand for high-performance lithium-ion batteries with high-capacity electrode materials,reducing the irreversible capacity loss in the initial cycle and compensating for the active lithium ... With the increasing market demand for high-performance lithium-ion batteries with high-capacity electrode materials,reducing the irreversible capacity loss in the initial cycle and compensating for the active lithium loss during the cycling process are critical challenges.In recent years,various prelithiation strategies have been developed to overcome these issues.Since these approaches are carried out under a wide range of conditions,it is essential to evaluate their suitability for large-scale commercial applications.In this review,these strategies are categorized based on different battery assembling stages that they are implemented in,including active material synthesis,the slurry mixing process,electrode pretreatment,and battery fabrication.Furthermore,their advantages and disadvantages in commercial production are discussed from the perspective of thermodynamics and kinetics.This review aims to provide guidance for the future development of prelithiation strategies toward commercialization,which will potentially promote the practical application of next-generation high-energy-density lithium-ion batteries. 展开更多
关键词 high-energy-density irreversible capacity loss lithium-ion batteries practical application prelithiation
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Experimental and Numerical Study on Progressive Collapse Analysis of a Glulam Frame Structure:I.Side Column Exposed to Fire
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作者 Xiaowu Cheng Xinyan Tao lu wang 《Journal of Renewable Materials》 SCIE EI 2023年第2期905-920,共16页
This paper presents experimental and numerical investigations on progressive collapse behavior of a two-story glulam frame when the side column is exposed to ISO834 standard fire.The collapse mechanism initiated by fi... This paper presents experimental and numerical investigations on progressive collapse behavior of a two-story glulam frame when the side column is exposed to ISO834 standard fire.The collapse mechanism initiated by fire is identified.The experimental results show that the progressive collapse of a glulam frame could be described for three stages,namely bending effect stage,catenary effect stage and failure stage,respectively.These stages are discussed in detail to understand the structural behavior before and during collapse.It is demonstrated that the entire frame slopes towards the side of the heated column,and the“overturning”collapse occurs eventually.The catenary effect of beams is the main reason for the progressive collapse of the frame.In addition,a finite element model of a glulam frame is established to simulate the progressive collapse behavior.The effects of axial loads on the columns are summarized.The numerical simulation results agree well with the experimental results,which could verify the effectiveness and practicability of finite element simulation.Furthermore,the progressive collapse resistance of the frame in practical design were proposed. 展开更多
关键词 COLLAPSE glulam frame structure FIRE failure mechanisms
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Outcomes and risk factors for failure of trabeculectomy in glaucomatous patients in Southwest China:a 325 eyes analysis
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作者 Zuo-Xin Qin Xi Ying +6 位作者 Qing Han lu wang Lian Tan Yu-Fei Xu Qiu-Xiang You Nan Wu Yong Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第3期367-374,共8页
AIM:To evaluate the outcomes and elucidate the failure factors for trabeculectomy with mitomycin C(MMC)in Southwest Chinese patients.METHODS:A retrospective correlational study was conducted on the glaucomatous patien... AIM:To evaluate the outcomes and elucidate the failure factors for trabeculectomy with mitomycin C(MMC)in Southwest Chinese patients.METHODS:A retrospective correlational study was conducted on the glaucomatous patients who underwent initial trabeculectomy with MMC in Southwest Hospital and had been followed up for 1-3y.A complete success for surgery is defined as a postoperative intraocular pressure(IOP)>5 and≤21 mm Hg and 20%reduction of IOP compared to preoperative,without IOP-lowering medications.A qualified success for surgery is defined as the abovementioned postoperative IOP with or without IOP-lowering medications.The primary outcomes were IOP,the number of IOP-lowering medications,and cumulative success rate.The secondary outcomes included best corrected visual acuity(BCVA),mean deviation(MD)of visual field,major complications,and risk factors for surgical failure.RESULTS:A total of 325 eyes of 261 glaucomatous patients had been included in our study.Both the mean IOP and the number of IOP-lowering medications were significantly decreased from 32.9±12.0 to 16.4±5.7 mm Hg(P<0.0001)and 3.0±0.9 to 0.9±1.0(P<0.0001),respectively,at the last visit.The cumulative complete success rate and qualified success rate were 77.8%and 92.0%at 1-year follow-up,and 47.2%and 77.7%at 3-year follow up.There were no significant differences in surgical outcomes between primary angle-closure glaucoma(PACG)and primary open angle glaucoma(POAG).In PACG patients,the success rates of trabeculectomy were comparable with those of phacotrabeculectomy.Hypertension(HR=1.904,P=0.011),encapsulated bleb(HR=2.756,P<0.001),and more preoperative topical medications(HR=2.475,P=0.008)were risk factors for surgical failure.CONCLUSION:The qualified success rate of trabeculectomy with MMC in glaucomatous patients in the cohort is 92.0%at 1-year,and 77.7%at 3-year follow up.Hypertension,encapsulated bleb,and more preoperative topical medications are associated with surgical failure. 展开更多
关键词 GLAUCOMA TRABECULECTOMY OUTCOMES risk factors
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A Review of the Application of Process Evaluation in Junior High School English Teaching under “Double Reduction”
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作者 lu wang 《Open Journal of Applied Sciences》 2023年第10期1681-1688,共8页
The “Double Reduction” policy is not only to reduce the excessive learning burden of students, but also to improve the quality of students’ learning and to promote their overall development. In order to achieve the... The “Double Reduction” policy is not only to reduce the excessive learning burden of students, but also to improve the quality of students’ learning and to promote their overall development. In order to achieve the goal of the “Double Reduction” policy, it is necessary to focus on the implementation of measures to strengthen process evaluation as proposed in the “General Plan for Deepening Education Evaluation Reform in a New Era”. Therefore, the article will analyze the current situation of the research from three aspects: the connotation of “Double Reduction” and process evaluation, process evaluation under “Double Reduction” and process evaluation in English teaching, and look forward to the future development trend, with the aim of implementing the “Double Reduction” policy and giving full play to process evaluation. The aim is to implement the policy of “Double Reduction” and give full play to the role of process evaluation, so as to effectively guide the practice of English teaching. 展开更多
关键词 Double Reduction Process Evaluation Middle School English
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花岗岩在不同温度劈裂载荷下的损伤演化与失稳前兆
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作者 王李昌 王璐 +1 位作者 徐蒙 隆威 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第3期977-994,共18页
为了阐明深地钻探中花岗岩在劈裂载荷与高温作用下的复杂机械和损伤特性,对经50~600℃处理的花岗岩试样进行巴西劈裂声发射(AE)试验。结果表明,温度变化会使花岗岩的机械与声发射特性发生改变,从而改变其破裂演化过程。当温度超过500℃... 为了阐明深地钻探中花岗岩在劈裂载荷与高温作用下的复杂机械和损伤特性,对经50~600℃处理的花岗岩试样进行巴西劈裂声发射(AE)试验。结果表明,温度变化会使花岗岩的机械与声发射特性发生改变,从而改变其破裂演化过程。当温度超过500℃时,花岗岩的抗拉强度大幅降低,剪切损伤模式占比增加。此外,破裂速率亦呈现明显增长趋势。在基于撞击数和能量计数的损伤参数演化曲线的基础上,定义“损伤参数突变点”来判断作为岩石破坏的前兆信息。基于撞击数的“突变点”比岩石失稳的信号提前到达,且岩石损伤越大,提前的时间越久。通过这个时间差,可以达到预警岩石失稳的效果。 展开更多
关键词 深地钻探 岩石损伤 声发射 高温 劈裂荷载
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有机-有机界面效应的原位及非原位研究
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作者 冀连连 王现鹏 +7 位作者 张莹莹 申学礼 薛娣 王璐 王滋 王文冲 黄丽珍 迟力峰 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第1期30-31,共2页
有机-有机异质结构已被广泛应用于各种有机电子器件,包括有机发光二极管(OLEDs)、有机场效应晶体管(OFETs)和有机太阳能电池等。全面理解有机-有机异质结构的界面效应,对于器件的设计和性能优化具有重要意义。然而由于有机半导体具有多... 有机-有机异质结构已被广泛应用于各种有机电子器件,包括有机发光二极管(OLEDs)、有机场效应晶体管(OFETs)和有机太阳能电池等。全面理解有机-有机异质结构的界面效应,对于器件的设计和性能优化具有重要意义。然而由于有机半导体具有多样的化学特性以及分子间较弱的范德华力,界面电荷传输特性与有机-有机电子结构、环境气氛等密切相关。在此,我们报道了随着顶层半导体并五苯(pentacene)的沉积,并五苯/酞菁氧钒(VOPc)异质结构的原位实时电学性能监测。结果显示,异质结构晶体管的p型迁移率从0.4 cm2∙V−1∙s^(−1)下降至0.2 cm2∙V−1∙s^(−1),而n型迁移率从0.01 cm2∙V−1∙s^(−1)迅速增加至约0.9 cm2∙V−1∙s^(−1)。这种n型输运行为的增强归因于pentacene向VOPc的界面电子转移效应以及由此导致的VOPc层中陷阱态的填充。此外,非原位实验对比表明,当晶体管制备过程暴露于大气时会明显抑制这种界面电荷转移效应,导致沉积pentacene后n型输运几乎没有得到改善。薄膜形态、开尔文探针力显微镜(KPFM)和X射线光电子能谱(XPS)的结果表明,界面处存在从pentacene到VOPc的电子转移。进一步的密度泛函理论(DFT)计算表明,由于pentacene/VOPc之间较强的相互作用,pentacene往VOPc的电荷转移量约为0.15 e。此外,O_(2)/H2O的存在会抑制这种界面电荷转移效应,这与我们的实验结果一致。本研究通过原位电学表征对有机-有机界面之间的电荷转移效应给出了深入解释,有利于进一步的器件性能优化及界面效应分析。 展开更多
关键词 有机-有机异质结构 原位表征 电荷转移效应 有机场效应晶体管 O_(2)/H2O掺杂
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Climate-Vegetation Coverage Interactions in the Hengduan Mountains Area, Southeastern Tibetan Plateau, and Their Downstream Effects
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作者 Congxi FANG Jinlei CHEN +4 位作者 Chaojun OUYANG lu wang Changfeng SUN Quan ZHANG Jun WEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期701-716,共16页
Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in ... Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate. 展开更多
关键词 Hengduan Mountains Area normalized difference vegetation index climate change net heat flux downstream effects
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Bilayer separator enabling dendrite-free zinc anode with ultralong lifespan >5000 h
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作者 lu wang Feifei wang +5 位作者 Zhe Ding Yingxin Liu Ziyi Zhang Chunpeng Yang Kian Ping Loh Quan-Hong Yang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期771-776,共6页
Aqueous zinc(Zn)batteries with Zn metal anodes are promising clean energy storage devices with intrinsic safety and low cost.However,Zn dendrite growth severely restricts the use of Zn anodes.To effectively suppress Z... Aqueous zinc(Zn)batteries with Zn metal anodes are promising clean energy storage devices with intrinsic safety and low cost.However,Zn dendrite growth severely restricts the use of Zn anodes.To effectively suppress Zn dendrite growth,we propose a bilayer separator consisting of commercial butter paper and glassfiber membrane.The dense cellulose-based butter paper(BP)with low zincophilicity and high mechanical properties prevents the pore-filling behavior of deposited Zn and related separator piercing,effectively suppressing the Zn dendrite growth.As a result,the bilayer separators endow the ZnjjZn symmetrical batteries with a superlong cycling life of Zn anodes(over 5000 h)at 0.5 mA cm^(-2) and the full batteries enhanced capacity retention,demonstrating the advancement of the bilayer separator to afford excellent cyclability of aqueous metal batteries. 展开更多
关键词 Zn battery Bilayer separator Butter paper Zn metal anode Zn dendrite
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Static-to-kinematic modeling and experimental validation of tendon-driven quasi continuum manipulators with nonconstant subsegment stiffness
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作者 郑先杰 丁萌 +2 位作者 刘辽雪 王璐 郭毓 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期316-326,共11页
Continuum robots with high flexibility and compliance have the capability to operate in confined and cluttered environments. To enhance the load capacity while maintaining robot dexterity, we propose a novel non-const... Continuum robots with high flexibility and compliance have the capability to operate in confined and cluttered environments. To enhance the load capacity while maintaining robot dexterity, we propose a novel non-constant subsegment stiffness structure for tendon-driven quasi continuum robots(TDQCRs) comprising rigid-flexible coupling subsegments.Aiming at real-time control applications, we present a novel static-to-kinematic modeling approach to gain a comprehensive understanding of the TDQCR model. The analytical subsegment-based kinematics for the multisection manipulator is derived based on screw theory and product of exponentials formula, and the static model considering gravity loading,actuation loading, and robot constitutive laws is established. Additionally, the effect of tension attenuation caused by routing channel friction is considered in the robot statics, resulting in improved model accuracy. The root-mean-square error between the outputs of the static model and the experimental system is less than 1.63% of the arm length(0.5 m). By employing the proposed static model, a mapping of bending angles between the configuration space and the subsegment space is established. Furthermore, motion control experiments are conducted on our TDQCR system, and the results demonstrate the effectiveness of the static-to-kinematic model. 展开更多
关键词 static-to-kinematic modeling scheme tendon-driven quasi continuum robot nonconstant subsegment stiffness tension attenuation effect
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LociScan,a tool for screening genetic marker combinations for plant variety discrimination
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作者 Yang Yang Hongli Tian +5 位作者 Hongmei Yi Zi Shi lu wang Yaming Fan Fengge wang Jiuran Zhao 《The Crop Journal》 SCIE CSCD 2024年第2期583-593,共11页
To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening m... To reduce the cost and increase the efficiency of plant genetic marker fingerprinting for variety discrimination,it is desirable to identify the optimal marker combinations.We describe a marker combination screening model based on the genetic algorithm(GA)and implemented in a software tool,Loci Scan.Ratio-based variety discrimination power provided the largest optimization space among multiple fitness functions.Among GA parameters,an increase in population size and generation number enlarged optimization depth but also calculation workload.Exhaustive algorithm afforded the same optimization depth as GA but vastly increased calculation time.In comparison with two other software tools,Loci Scan accommodated missing data,reduced calculation time,and offered more fitness functions.In large datasets,the sample size of training data exerted the strongest influence on calculation time,whereas the marker size of training data showed no effect,and target marker number had limited effect on analysis speed. 展开更多
关键词 Plant variety discrimination Genetic marker combination Variety discrimination power Genetic algorithm
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Clinical features and prognostic factors of duodenal neuroendocrine tumours:A comparative study of ampullary and nonampullary regions
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作者 Sa Fang Yu-Peng Shi +2 位作者 lu wang Shuang Han Yong-Quan Shi 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期907-918,共12页
BACKGROUND Duodenal neuroendocrine tumours(DNETs)are rare neoplasms.However,the incidence of DNETs has been increasing in recent years,especially as an incidental finding during endoscopic studies.Regrettably,there is... BACKGROUND Duodenal neuroendocrine tumours(DNETs)are rare neoplasms.However,the incidence of DNETs has been increasing in recent years,especially as an incidental finding during endoscopic studies.Regrettably,there is no consensus regarding the ideal treatment of DNETs.Even there are few studies on the clinical features and survival analysis of DNETs.AIM To analyze the clinical characteristics and prognostic factors of patients with duodenal neuroendocrine tumours.METHODS The clinical data of DNETs diagnosed in the First Affiliated Hospital of Air Force Military Medical University from June 2011 to July 2022 were collected.Neuroen-docrine tumours located in the ampulla area of the duodenum were divided into the ampullary region group;neuroendocrine tumours in any part of the duo-denum outside the ampullary area were divided into the nonampullary region group.Using a retrospective study,the clinical characteristics of the two groups and risk factors affecting the survival of DNET patients were analysed.RESULTS Twenty-nine DNET patients were screened.The male to female ratio was 1:1.9,and females comprised the majority.The ampullary region group accounted for 24.1%(7/29),while the nonampullary region group accounted for 75.9%(22/29).When diagnosed,the clinical symptoms of the ampullary region group were mainly abdominal pain(85.7%),while those of the nonampullary region groups were mainly abdominal distension(59.1%).There were differences in the composition of staging of tumours between the two groups(Fisher's exact probability method,P=0.001),with nonampullary stage II tumours(68.2%)being the main stage(P<0.05).After the diagnosis of DNETs,the survival rate of the ampullary region group was 14.3%(1/7),which was lower than that of 72.7%(16/22)in the nonampullary region group(Fisher's exact probability method,P=0.011).The survival time of the ampullary region group was shorter than that of the nonampullary region group(P<0.000).The median survival time of the ampullary region group was 10.0 months and that of the nonampullary region group was 451.0 months.Multivariate analysis showed that tumours in the ampulla region and no surgical treatment after diagnosis were independent risk factors for the survival of DNET patients(HR=0.029,95%CI 0.004-0.199,P<0.000;HR=12.609,95%CI:2.889-55.037,P=0.001).Further analysis of nonampullary DNET patients showed that the survival time of patients with a tumour diameter<2 cm was longer than that of patients with a tumour diameter≥2 cm(t=7.243,P=0.048).As of follow-up,6 patients who died of nonampullary DNETs had a tumour diameter that was≥2 cm,and 3 patients in stage IV had liver metastasis.Patients with a tumour diameter<2 cm underwent surgical treatment,and all survived after surgery.CONCLUSION Surgical treatment is a protective factor for prolonging the survival of DNET patients.Compared to DNETs in the ampullary region,patients in the nonampullary region group had a longer survival period.The liver is the organ most susceptible to distant metastasis of nonampullary DNETs. 展开更多
关键词 DUODENUM NEUROENDOCRINE TUMOUR Ampullary Nonampullary Clinical features PROGNOSTIC
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Wave nature of Rosensweig instability
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作者 李柳 李德才 +2 位作者 戚志强 王璐 张志力 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期471-479,共9页
The explicit analytical solution of Rosensweig instability spikes'shapes obtained by Navier-Stokes(NS)equation in diverse magnetic field H vertical to the flat free surface of ferrofluids are systematically studie... The explicit analytical solution of Rosensweig instability spikes'shapes obtained by Navier-Stokes(NS)equation in diverse magnetic field H vertical to the flat free surface of ferrofluids are systematically studied experimentally and theoretically.After carefully analyzing and solving the NS equation in elliptic form,the force balanced surface equations of spikes in Rosensweig instability are expressed as cosine wave in perturbated magnetic field and hyperbolic tangent in large magnetic field,whose results both reveal the wave-like nature of Rosensweig instability.The results of hyperbolic tangent form are perfectly fitted to the experimental results in this paper,which indicates that the analytical solution is basically correct.Using the forementioned theoretical results,the total energy of the spike distribution pattern is calculated.By analyzing the energy components under different magnetic field intensities H,the hexagon-square transition of Rosensweig instability is systematically discussed and explained in an explicit way. 展开更多
关键词 FERROFLUIDS Rosensweig instability hexagon-square transition
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Effects of a periodic intermittent theta burst stimulation in Alzheimer's disease
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作者 Xingqi Wu Yibing Yan +12 位作者 Panpan Hu lu wang Yue Wu Pan Wu Zhi Geng Guixian Xiao Shanshan Zhou Gongjun Ji Bensheng Qiu Ling Wei Yanghua Tian Hesheng Liu Kai wang 《General Psychiatry》 CSCD 2024年第1期53-63,共11页
Background Previous studies havedemonstrated that excitatory repetitive transcranial magnetic stimulation(rTMS)can improve the cognitive function of patients with Alzheimer's disease(AD).Intermittent theta burst s... Background Previous studies havedemonstrated that excitatory repetitive transcranial magnetic stimulation(rTMS)can improve the cognitive function of patients with Alzheimer's disease(AD).Intermittent theta burst stimulation(iTBS)is a novel excitatory rTMS protocol for brain activity stimulation with the ability to induce long-term potentiation-like plasticity and represents a promising treatment for AD.However,the long-term effects of iTBS on cognitive decline and brain structure in patients with AD areunknown.Aims We aimed to explore whether repeating accelerated iTBS every three months could slow down the cognitive decline in patients with AD.Methods In this randomised,assessor-blinded,controlled trial,iTBS was administered to the left dorsolateral prefrontal cortex(DLPFC)of 42 patients with AD for 14days every 13weeks.Measurements included the Montreal Cognitive Assessment(MoCA),a comprehensive neuropsychological battery,and the grey matter volume(GMV)of the hippocampus.Patients were evaluated at baseline and after follow-up.The longitudinal pipeline of the Computational Anatomy Toolbox for SPM was used to detect significant treatment-related changes over time.Results The iTBS group maintained MoCA scores relative to the control group(t=3.26,p=0.013)and reduced hippocampal atrophy,which was significantly correlated with global degeneration scale changes.The baseline Mini-Mental State Examination(MMSE)score,apolipoprotein E genotype and Clinical Dementia Rating were indicative of MoCA scores at follow-up.Moreover,the GMV of the left(t=0.08,p=0.996)and right(t=0.19,p=0.977)hippocampus were maintained in the active group but significantly declined in the control group(left:t=4.13,p<0.001;right:t=5.31,p<0.001).GMV change in the left(r=0.35,p=0.023)and right(r=0.36,p=0.021)hippocampus across the intervention positively correlated with MoCA changes;left hippocampal GMV change was negatively correlated with global degeneration scale(r=-0.32,p=0.041)changes.Conclusions DLPFC-iTBS maybe a feasible and easy-to-implement non-pharmacological intervention to slow down the progressive decline of overall cognition and quality of life in patients with AD,providing a new AD treatment option.Trial registration number NCT04754152. 展开更多
关键词 STIMULATION ALZHEIMER maintained
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达格列净治疗慢性心力衰竭的快速卫生技术评估 被引量:1
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作者 魏安华 王璐 +2 位作者 曾露 贡雪芃 刘东 《药物流行病学杂志》 CAS 2023年第5期554-563,共10页
目的快速评价达格列净治疗慢性心力衰竭(CHF)的有效性、安全性和经济性,为临床药物选择和决策提供循证依据。方法计算机检索PubMed、Embase、Web of Science、The Cochrane Library、CNKI和WanFang Data数据库,同时检索相关卫生技术评估... 目的快速评价达格列净治疗慢性心力衰竭(CHF)的有效性、安全性和经济性,为临床药物选择和决策提供循证依据。方法计算机检索PubMed、Embase、Web of Science、The Cochrane Library、CNKI和WanFang Data数据库,同时检索相关卫生技术评估(HTA)网站和数据库,搜集达格列净治疗CHF的高质量临床证据、经济学评价文献,检索时限均为从建库至2022年7月24日。2名评价者独立筛选文献、提取资料并评价纳入研究的质量后,对结果进行定性描述与分析。结果共纳入文献17篇,其中系统评价/Meta分析6篇、药物经济学研究11篇。有效性分析结果显示,相比于安慰剂,达格列净可降低CHF患者的全因死亡率、心血管死亡和心力衰竭再入院率等结局指标(P<0.05),而对实验室指标(如左室射血分数和N-端脑利钠肽前体)影响的差异无统计学意义(P>0.05)。安全性分析显示,达格列净不增加严重不良事件、低血糖、容量衰竭、尿路感染和肾功能损伤的发生风险(P>0.05),且能改善代谢性指标,如收缩压和体重(P<0.05)。间接比较分析显示,不同钠-葡萄糖协同转运蛋白2抑制剂(SGLT2i)之间有效性和安全性均未见明显区别。经济性分析结果显示,虽然不同国家或地区不同支付方的意愿支付阈值不同,但达格列净普遍具有成本-效果优势。结论达格列净治疗CHF具有良好的有效性、安全性和经济性,但目前尚缺乏SGLT2i之间头对头直接比较的临床研究和评价分析。 展开更多
关键词 达格列净 慢性心力衰竭 有效性 安全性 经济性 快速卫生技术评估
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Seasonal and interannual variability of water mass sources of Indonesian throughflow in the Maluku Sea and the Halmahera Sea 被引量:3
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作者 lu wang Lei Zhou +3 位作者 Lingling Xie Quanan Zheng Qiang Li Mingming Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第4期58-71,共14页
So far, large uncertainties of the Indonesian throughflow(ITF) reside in the eastern Indonesian seas, such as the Maluku Sea and the Halmahera Sea. In this study, the water sources of the Maluku Sea and the Halmahera ... So far, large uncertainties of the Indonesian throughflow(ITF) reside in the eastern Indonesian seas, such as the Maluku Sea and the Halmahera Sea. In this study, the water sources of the Maluku Sea and the Halmahera Sea are diagnosed at seasonal and interannual timescales and at different vertical layers, using the state-of-the-art simulations of the Ocean General Circulation Model(OGCM) for Earth Simulator(OFES). Asian monsoon leaves clear seasonal footprints on the eastern Indonesian seas. Consequently, the subsurface waters(around 24.5σ_θ and at ~150 m) in both the Maluku Sea and the Halmahera Sea stem from the South Pacific(SP) during winter monsoon, but during summer monsoon the Maluku Sea is from the North Pacific(NP), and the Halmahera Sea is a mixture of waters originating from the NP and the SP. The monsoon impact decreases with depth, so that in the Maluku Sea, the intermediate water(around 26.8σ_θ and at ~480 m) is always from the northern Banda Sea and the Halmahera Sea water is mainly from the SP in winter and the Banda Sea in summer. The deep waters(around27.2σ_θ and at ~1 040 m) in both seas are from the SP, with weak seasonal variability. At the interannual timescale,the subsurface water in the Maluku Sea originates from the NP/SP during El Ni?o/La Ni?a, while the subsurface water in the Halmahera Sea always originates from the SP. Similar to the seasonal variability, the intermediate water in Maluku Sea mainly comes from the Banda Sea and the Halmahera Sea always originates from the SP. The deep waters in both seas are from the SP. Our findings are helpful for drawing a comprehensive picture of the water properties in the Indonesian seas and will contribute to a better understanding of the ocean-atmosphere interaction over the maritime continent. 展开更多
关键词 water mass INDONESIAN THROUGHFLOW MONSOON ENSO Maluku SEA Halmahera SEA
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