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Highly Elastic,Bioresorbable Polymeric Materials for Stretchable,Transient Electronic Systems
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作者 Jeong‑Woong Shin Dong‑Je Kim +12 位作者 Tae‑Min Jang Won Bae Han Joong Hoon Lee Gwan‑Jin Ko Seung Min Yang Kaveti Rajaram Sungkeun Han Heeseok Kang Jun Hyeon Lim Chan‑Hwi Eom Amay J.Bandodkar Hanul Min Suk‑Won Hwang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期1-13,共13页
Substrates or encapsulants in soft and stretchable formats are key components for transient,bioresorbable electronic systems;however,elastomeric polymers with desired mechanical and biochemical properties are very lim... Substrates or encapsulants in soft and stretchable formats are key components for transient,bioresorbable electronic systems;however,elastomeric polymers with desired mechanical and biochemical properties are very limited compared to nontransient counterparts.Here,we introduce a bioresorbable elastomer,poly(glycolide-co-ε-caprolactone)(PGCL),that contains excellent material properties including high elongation-at-break(<1300%),resilience and toughness,and tunable dissolution behaviors.Exploitation of PGCLs as polymer matrices,in combination with conducing polymers,yields stretchable,conductive composites for degradable interconnects,sensors,and actuators,which can reliably function under external strains.Integration of device components with wireless modules demonstrates elastic,transient electronic suture system with on-demand drug delivery for rapid recovery of postsurgical wounds in soft,time-dynamic tissues. 展开更多
关键词 Biodegradable elastomer Conductive polymer composites Biomedical device transient electronics
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Transient Stability Preventive Control of Wind Farm Connected Power System Considering the Uncertainty
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作者 Yuping Bian Xiu Wan Xiaoyu Zhou 《Energy Engineering》 EI 2024年第6期1637-1656,共20页
To address uncertainty as well as transient stability constraints simultaneously in the preventive control of windfarm systems, a novel three-stage optimization strategy is established in this paper. In the first stag... To address uncertainty as well as transient stability constraints simultaneously in the preventive control of windfarm systems, a novel three-stage optimization strategy is established in this paper. In the first stage, the probabilisticmulti-objective particle swarm optimization based on the point estimate method is employed to cope with thestochastic factors. The transient security region of the system is accurately ensured by the interior point methodin the second stage. Finally, the verification of the final optimal objectives and satisfied constraints are enforcedin the last stage. Furthermore, the proposed strategy is a general framework that can combine other optimizationalgorithms. The proposed methodology is tested on the modified WSCC 9-bus system and the New England 39-bussystem. The results verify the feasibility of the method. 展开更多
关键词 transient preventive control chance-constrained programming multi-objective PSO TSCOPF wind farm
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Migratable Power System Transient Stability AssessmentMethod Based on Improved XGBoost
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作者 Ying Qu Jinhao Wang +4 位作者 Xueting Cheng Jie Hao Weiru Wang Zhewen Niu Yuxiang Wu 《Energy Engineering》 EI 2024年第7期1847-1863,共17页
The data-driven transient stability assessment(TSA)of power systems can predict online real-time prediction by learning the temporal features before and after faults.However,the accuracy of the assessment is limited b... The data-driven transient stability assessment(TSA)of power systems can predict online real-time prediction by learning the temporal features before and after faults.However,the accuracy of the assessment is limited by the quality of the data and has weak transferability.Based on this,this paper proposes a method for TSA of power systems based on an improved extreme gradient boosting(XGBoost)model.Firstly,the gradient detection method is employed to remove noise interference while maintaining the original time series trend.On this basis,a focal loss function is introduced to guide the training of theXGBoostmodel,enhancing the deep exploration of minority class samples to improve the accuracy of the model evaluation.Furthermore,to improve the generalization ability of the evaluation model,a transfer learning method based on model parameters and sample augmentation is proposed.The simulation analysis on the IEEE 39-bus system demonstrates that the proposed method,compared to the traditional machine learning-based transient stability assessment approach,achieves an average improvement of 2.16%in evaluation accuracy.Specifically,under scenarios involving changes in topology structure and operating conditions,the accuracy is enhanced by 3.65%and 3.11%,respectively.Moreover,the model updating efficiency is enhanced by 14–15 times,indicating the model’s transferable and adaptive capabilities across multiple scenarios. 展开更多
关键词 transient stability assessment DATA-DRIVEN segmented focusing approximation PORTABILITY
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An efficient transient gene expression system for protein subcellular localization assay and genome editing in citrus protoplasts 被引量:2
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作者 Wenhui Yang Jiaqin Ren +6 位作者 Wanrong Liu Dan Liu Kaidong Xie Fei Zhang Pengwei Wang Wenwu Guo Xiaomeng Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期425-436,共12页
Protoplast has been widely used in biotechnologies to circumvent the breeding obstacles in citrus, including long juvenility, polyembryony, and male/female sterility. The protoplast-based transient gene expression sys... Protoplast has been widely used in biotechnologies to circumvent the breeding obstacles in citrus, including long juvenility, polyembryony, and male/female sterility. The protoplast-based transient gene expression system is a powerful tool for gene functional characterization and CRISPR/Cas9 genome editing in higher plants, but it has not been widely used in citrus. In this study, the polyethylene glycol(PEG)-mediated method was optimized for citrus callus protoplast transfection, with an improved transfection efficiency of 68.4%. Consequently, the efficiency of protein subcellular localization assay was increased to 65.8%, through transient expression of the target gene in protoplasts that stably express the fluorescent organelle marker protein. The gene editing frequencies in citrus callus protoplasts reached 14.2% after transient expression of CRISPR/Cas9 constructs. We demonstrated that the intronic polycistronic tRNAgRNA(inPTG) genome editing construct was functional in both the protoplast transient expression system and epicotyl stable transformation system in citrus. With this optimized protoplast transient expression system, we improved the efficiency of protein subcellular localization assay and developed the genome editing system in callus protoplasts, which provides an approach for prompt test of CRISPR vectors. 展开更多
关键词 CITRUS Callus protoplast transient transfection Subcellular localization Genome editing
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Mutation in the Agrobacterium his I gene enhances transient expression in pepper 被引量:1
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作者 Dan Liu Shengnan Zhao +3 位作者 Jubin Wang Xi Zhang Yingtian Deng Feng Li 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期809-822,共14页
Agrobacterium-mediated plant transformation is widely used in plant genetic engineering.However,its efficiency is limited by plant immunity against Agrobacterium.Chili pepper(Capsicum annuum L.)is an important vegetab... Agrobacterium-mediated plant transformation is widely used in plant genetic engineering.However,its efficiency is limited by plant immunity against Agrobacterium.Chili pepper(Capsicum annuum L.)is an important vegetable that is recalcitrant to Agrobacterium-mediated transformation.In this work,Agrobacterium was found to induce a strong immune response in pepper,which might be the reason for T-DNA being difficult to express in pepper.An Agrobacterium mutant screen was conducted and a point mutation in the hisI gene was identified due to a weak immune response and enhanced transient expression mediated by this Agrobacterium mutant in pepper leaves.Further genetic analysis revealed that histidine biosynthesis deficiency caused by mutations in many genes of this pathway led to reduced pepper cell death,presumably due to reduced bacterial growth.However,mutation analysis of threonine and tryptophan biosynthesis genes showed that the biosynthesis of different amino acids may play different roles in Agrobacterium growth and stimulating the pepper immune response.The possible application of Agrobacterium amino acid biosynthesis mutations in plant biology was discussed. 展开更多
关键词 Capsicum annuum L. AGROBACTERIUM transient transformation efficiency MUTATION Amino acid Immune response
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Transient receptor potential channels as predictive marker and potential indicator of chemoresistance in colon cancer 被引量:1
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作者 WEI HU THOMAS WARTMANN +5 位作者 MARCO STRECKER ARISTOTELIS PERRAKIS ROLAND CRONER ARPAD SZALLASI WENJIE SHI ULF D.KAHLERT 《Oncology Research》 SCIE 2024年第1期227-239,共13页
Transient receptor potential(TRP)channels are strongly associated with colon cancer development and progression.This study leveraged a multivariate Cox regression model on publicly available datasets to construct a TR... Transient receptor potential(TRP)channels are strongly associated with colon cancer development and progression.This study leveraged a multivariate Cox regression model on publicly available datasets to construct a TRP channels-associated gene signature,with further validation of signature in real world samples from our hospital treated patient samples.Kaplan-Meier(K-M)survival analysis and receiver operating characteristic(ROC)curves were employed to evaluate this gene signature’s predictive accuracy and robustness in both training and testing cohorts,respectively.Additionally,the study utilized the CIBERSORT algorithm and single-sample gene set enrichment analysis to explore the signature’s immune infiltration landscape and underlying functional implications.The support vector machine algorithm was applied to evaluate the signature’s potential in predicting chemotherapy outcomes.The findings unveiled a novel three TRP channels-related gene signature(MCOLN1,TRPM5,and TRPV4)in colon adenocarcinoma(COAD).The ROC and K-M survival curves in the training dataset(AUC=0.761;p=1.58e-05)and testing dataset(AUC=0.699;p=0.004)showed the signature’s robust predictive capability for the overall survival of COAD patients.Analysis of the immune infiltration landscape associated with the signature revealed higher immune infiltration,especially an increased presence of M2 macrophages,in high-risk group patients compared to their low-risk counterparts.High-risk score patients also exhibited potential responsiveness to immune checkpoint inhibitor therapy,evident through increased CD86 and PD-1 expression profiles.Moreover,the TRPM5 gene within the signature was highly expressed in the chemoresistance group(p=0.00095)and associated with poor prognosis(p=0.036)in COAD patients,highlighting its role as a hub gene of chemoresistance.Ultimately,this signature emerged as an independent prognosis factor for COAD patients(p=6.48e-06)and expression of model gene are validated by public data and real-world patients.Overall,this bioinformatics study provides valuable insights into the prognostic implications and potential chemotherapy resistance mechanisms associated with TRPs-related genes in colon cancer. 展开更多
关键词 Colon cancer transient receptor potential channels Prognostic signature Chemotherapy efficiency TRPM5
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Diagnostic role of transient elastography in patients with autoimmune liver diseases:A systematic review and meta-analysis
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作者 Hong Chen Yue Shen +5 位作者 Sheng-Di Wu Qin Zhu Cheng-Zhao Weng Jun Zhang Mei-Xia Wang Wei Jiang 《World Journal of Gastroenterology》 SCIE CAS 2023年第39期5503-5525,共23页
BACKGROUND Noninvasive methods have been developed to detect fibrosis in many liver diseases due to the limits of liver biopsy.However,previous studies have focused primarily on chronic viral hepatitis and nonalcoholi... BACKGROUND Noninvasive methods have been developed to detect fibrosis in many liver diseases due to the limits of liver biopsy.However,previous studies have focused primarily on chronic viral hepatitis and nonalcoholic fatty liver disease.The diagnostic value of transient elastography for autoimmune liver diseases(AILDs)is worth studying.AIM To compare the diagnostic accuracy of imaging techniques with serum biomarkers of fibrosis in AILD.METHODS The PubMed,Cochrane Library and EMBASE databases were searched.Studies evaluating the efficacy of noninvasive methods in the diagnosis of AILDs[autoimmune hepatitis(AIH),primary biliary cholangitis(PBC)and primary sclerosing cholangitis(PSC)]were included.The summary area under the receiver operating characteristic curve(AUROC),diagnostic odds ratio,sensitivity and specificity were used to assess the accuracy of these noninvasive methods for staging fibrosis.RESULTS A total of 60 articles were included in this study,and the number of patients with AIH,PBC and PSC was 1594,3126 and 501,respectively.The summary AUROC of transient elastography in the diagnosis of significant fibrosis,advanced fibrosis and cirrhosis in patients with AIH were 0.84,0.88 and 0.90,respectively,while those in patients with PBC were 0.93,0.93 and 0.91,respectively.The AUROC of cirrhosis for patients with PSC was 0.95.However,other noninvasive indices(aspartate aminotransferase to platelet ratio index,aspartate aminotransferase/alanine aminotransferase ratio,fibrosis-4 index)had corresponding AUROCs less than 0.80.CONCLUSION Transient elastography exerts better diagnostic accuracy in AILD patients,especially in PBC patients.The appropriate cutoff values for staging advanced fibrosis and cirrhosis ranged from 9.6 to 10.7 and 14.4 to 16.9 KPa for PBC patients. 展开更多
关键词 Liver stiffness Serum parameter Liver fibrosis Noninvasive diagnosis transient elastography Autoimmune liver disease
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Transient liquid phase bonding of DD5 superalloy using a designed interlayer: microstructure and mechanical properties 被引量:1
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作者 周昌杰 范骁乐 +3 位作者 朱立华 陈闯 贺建超 计红军 《China Welding》 CAS 2024年第2期1-10,共10页
Nickel based single crystal superalloy is currently widely used as the material for turbine blades in aerospace engines.However,metallurgical defects during the manufacturing process and damage during harsh environmen... Nickel based single crystal superalloy is currently widely used as the material for turbine blades in aerospace engines.However,metallurgical defects during the manufacturing process and damage during harsh environmental service are inevitable challenges for turbine blades.Therefore,bonding techniques play a very important role in the manufacturing and repair of turbine blades.The transient liquid phase(TLP)bonding of DD5 Ni-based single crystal superalloy was performed using the designed H1 interlayer.A new third-generation Ni-based superalloy T1 powder was mixed with H1 powder as another interlayer to improve the mechanical properties of the bonded joints.The res-ults show that,such a designed H1 interlayer is beneficial to the improvement of shear strength of DD5 alloy bonded joints by adjusting the bonding temperature and the prolongation of holding time.The maximum shear strength at room temperature of the joint with H1 interlayer reached 681 MPa when bonded at 1260℃for 3 h.The addition of T1 powder can effectively reduce holding time or relatively lower bond-ing temperature,while maintaining relatively high shear strength.When 1 wt.%T1 powder was mixed into H1 interlayer,the maximum room temperature shear strength of the joint bonded at 1260℃reached 641 MPa,which could be obtained for only 1 h.Considering the bonding temperature and the efficiency,the acceptable process parameter of H1+5 wt.%T1 interlayer was 1240℃/2 h,and the room tem-perature shear strength reached 613 MPa. 展开更多
关键词 Ni-based superalloy powder transient liquid phase bonded joint shear strength
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Diagnostic value of ABCD2 and ABCD3-Ⅰ risk scoring systems in determining one-month risk of stroke in patients with transient ischemic attack: An observational study
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作者 Tuncay Aslan Serkan Emre Eroğlu +3 位作者 Mehmet Muzafferİslam SerdarÖzdemir Gökhan Aksel Abdullah Algın 《Journal of Acute Disease》 2023年第5期192-197,共6页
Objective:To compare the diagnostic value of the ABCD2 and ABCD3-栺scoring systems in predicting the development of a 30-day neurological event in adult patients with transient ischemic attack(TIA)presenting to the em... Objective:To compare the diagnostic value of the ABCD2 and ABCD3-栺scoring systems in predicting the development of a 30-day neurological event in adult patients with transient ischemic attack(TIA)presenting to the emergency department.Methods:The study was observational and prospective and was conducted in a single center.The diagnostic values of the ABCD2 and ABCD3-栺scores in predicting a neurological event within one month were compared in patients diagnosed with TIA in the emergency department.Results:A statistically significant difference was observed between groups with or without stroke within one month in terms of both the ABCD2 and ABCD3-栺scores(P=0.044 and P=0.029,respectively).There was no statistically significant difference between the patients with and without a recurrent TIA within one month in relation to the ABCD2 score(P=0.934),but a statistically significant difference was found in the ABCD3-栺scores of these groups(P<0.001).Conclusions:Both the ABCD2 and ABCD3-栺scoring systems could predict ischemic stroke within 30 days of TIA,the ABCD3-栺score is more effective than the ABCD2 score in the prediction of TIA recurrence. 展开更多
关键词 transient ischemic attack STROKE Emergency services Risk reduction behavior Risk assessment Risk factors
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Effects of transient temperature gradient on frost heave of saturated silty clay in an open system
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作者 HongYan Ma YuanFang Cui +2 位作者 JianQiao Zhang Song Li Song Xu 《Research in Cold and Arid Regions》 CSCD 2023年第6期268-277,共10页
Frost heave in seasonally frozen regions is a one-dimensional process that could severely damage infrastructure subgrades.Stress state,temperature and water migration are important factors for frost heave.This work in... Frost heave in seasonally frozen regions is a one-dimensional process that could severely damage infrastructure subgrades.Stress state,temperature and water migration are important factors for frost heave.This work investigated the effects of soil temperature and volumetric water content on the transient frost heave ratio during the freezing of saturated silty clay in an open system and analyzed the relationships between the transient frost heave ratio and freezing rate and between temperature gradient and frost heave rate.The results show that the frost heave ratio,frost heave rate,and freezing rate are positively correlated with the temperature gradient since the temperature gradient drives the water migration during freezing,indicating the transient temperature gradient could be used to evaluate the frost heave of saturated silty clay.The transient freezing rate and transient frost heave ratio are logarithmically related to the transient frost heave ratio and transient temperature gradient,respectively.The effects of transient temperature gradient on frost heave are the principal mechanism responsible for different frost heave characteristics and uneven frost heave along a subgrade of the same soil type. 展开更多
关键词 Saturated silty clay Frost heave transient temperature gradient Frost heave ratio Frost heave rate
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To scan or not to scan:Use of transient elastography in an integrated health system
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作者 Libby Stein Rasham Mittal +2 位作者 Hubert Song Joanie Chung Amandeep Sahota 《World Journal of Hepatology》 2023年第3期419-430,共12页
BACKGROUND Non-invasive tests,such as Fibrosis-4 index and transient elastography(com-monly FibroScan),are utilized in clinical pathways to risk stratify and diagnose non-alcoholic fatty liver disease(NAFLD).In 2018,a... BACKGROUND Non-invasive tests,such as Fibrosis-4 index and transient elastography(com-monly FibroScan),are utilized in clinical pathways to risk stratify and diagnose non-alcoholic fatty liver disease(NAFLD).In 2018,a clinical decision support tool(CDST)was implemented to guide primary care providers(PCPs)on use of FibroScan for NAFLD.AIM To analyze how this CDST impacted health care utilization and patient outcomes.METHODS We performed a retrospective review of adults who had FibroScan for NAFLD indication from January 2015 to December 2017(pre-CDST)or January 2018 to December 2020(post-CDST).Outcomes included FibroScan result,laboratory tests,imaging studies,specialty referral,patient morbidity and mortality.RESULTS We identified 958 patients who had FibroScan,115 before and 843 after the CDST was implemented.The percentage of FibroScans ordered by PCPs increased from 33%to 67.1%.The percentage of patients diagnosed with early F1 fibrosis,on a scale from F0 to F4,increased from 7.8%to 14.2%.Those diagnosed with ad-vanced F4 fibrosis decreased from 28.7%to 16.5%.There were fewer laboratory tests,imaging studies and biopsy after the CDST was implemented.Though there were more specialty referrals placed after the CDST was implemented,multivariate analysis revealed that healthcare utilization aligned with fibrosis score,whereby patients with more advanced disease had more referrals.Very few patients were hospitalized or died.CONCLUSION This CDST empowered PCPs to diagnose and manage patients with NAFLD with appropriate allocation of care towards patients with more advanced disease. 展开更多
关键词 Non-alcoholic fatty liver disease transient elastography FIBROSCAN Clinical decision support tool Health care utilization Primary care
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On the analytical solution of transient friction in channel flows
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作者 F.J.GARCíA-GARCíA P.FARINAS-ALVARINO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第8期1447-1466,共20页
The transient friction in channel mean flows is the sum of two contributions,i.e.,the underlying laminar flow(ULF)and the purely turbulent component(PTC),and the contributions are analyzed separately by theoretical ex... The transient friction in channel mean flows is the sum of two contributions,i.e.,the underlying laminar flow(ULF)and the purely turbulent component(PTC),and the contributions are analyzed separately by theoretical experiments.It is found that,the transient friction may be higher or remarkably lower than that in equal-Reynolds number steady-state flows.The universal time constant for plane-parallel laminar flows is reported,and the role of the time constant in a turbulent mean flow is examined.It is shown that the time constant is related to the turbulence's frozen time.Finally,a study of the logarithmic layer during the transient flow is accomplished,which shows that the logarithmic layer is destroyed. 展开更多
关键词 transient friction transient flow unsteady channel flow
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Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution
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作者 Yan-Zhong Liang Bai-Lu Teng Wan-Jing Luo 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1765-1779,共15页
During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional well.However,in all existing studies,it i... During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional well.However,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field applications.Therefore,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux distribution.Specifically,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow behavior.By using the finite difference method,we can obtain the numerical solutions of the transient flow within the wellbore.With the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the wellbore.The complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient flow.Subsequently,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional well.The computation results show that the flux variation along the direction well has a significant effect on pressure responses.In addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial flow.The horizontal linear flow can be observed only if the formation thickness is much smaller than the well length.Furthermore,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore. 展开更多
关键词 Directional well Pressure transient behavior Semi-analytical model Non-uniform flux
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Kinematic analysis of flexible bipedal robotic systems
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作者 R.FAZEL A.M.SHAFEI S.R.NEKOO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第5期795-818,共24页
In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous researchers.What distinguishes the present research from similar works is the considera... In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous researchers.What distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic systems.This is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases considerably.Moreover,the human leg bones that are involved in walking are supported by viscoelastic muscles and ligaments.Therefore,for achieving more exact results,it is essential to model the robot links with viscoelastic properties.To this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of motion.The most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational force.The extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned goal.To overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue problem.By solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are determined.The effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of robotic systems are also studied.The findings of this parametric study reveal that the increase in the Kelvin-Voigt coefficient enhances the stability of the robotic system,while the increase in the modulus of elasticity has an opposite effect. 展开更多
关键词 bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient
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Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow
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作者 Yang Wang Jia Zhang +2 位作者 Shi-Long Yang Ze-Xuan Xu Shi-Qing Cheng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期343-351,共9页
Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinni... Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective permeability.Meanwhile,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant breakage.In this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer flooding.The hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer solution.The combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir pressure.Compared with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore section.The field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and the far-wellbore section with low fracture conductivity.The novelty of this paper is the analysis of pressure performances caused by the fracture dynamics and polymer rheology,as well as an analysis method that derives formation and fracture parameters based on the pressure and its derivative curves. 展开更多
关键词 Polymer flooding Non-Newtonian fluid Non-uniform fracture conductivity Two-phase flow Pressure transient analysis
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Transient Response and Ionic Dynamics in Organic Electrochemical Transistors
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作者 Chao Zhao Jintao Yang Wei Ma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期191-223,共33页
The rapid development of organic electrochemical transistors(OECTs)has ushered in a new era in organic electronics,distinguishing itself through its application in a variety of domains,from high-speed logic circuits t... The rapid development of organic electrochemical transistors(OECTs)has ushered in a new era in organic electronics,distinguishing itself through its application in a variety of domains,from high-speed logic circuits to sensitive biosensors,and neuromorphic devices like artificial synapses and organic electrochemical random-access memories.Despite recent strides in enhancing OECT performance,driven by the demand for superior transient response capabilities,a comprehensive understanding of the complex interplay between charge and ion transport,alongside electron–ion interactions,as well as the optimization strategies,remains elusive.This review aims to bridge this gap by providing a systematic overview on the fundamental working principles of OECT transient responses,emphasizing advancements in device physics and optimization approaches.We review the critical aspect of transient ion dynamics in both volatile and non-volatile applications,as well as the impact of materials,morphology,device structure strategies on optimizing transient responses.This paper not only offers a detailed overview of the current state of the art,but also identifies promising avenues for future research,aiming to drive future performance advancements in diversified applications. 展开更多
关键词 Organic electrochemical transistors transient response Ion dynamics Electronic dynamics Volatility and non-volatility
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Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework
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作者 Jintao Zhang Xingling Shao +1 位作者 Wendong Zhang Zongyu Zuo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期278-287,共10页
This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the fe... This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular spacing.In addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any overshoots.The significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient profiles.Furthermore,all variables existing in the entire system are analyzed to be convergent.Simulation and experimental results are provided to validate the utility of suggested solution. 展开更多
关键词 Multi-circular formation Reinforced transient profiles Nonholonomic vehicles Path following
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Identification of transient receptor potential channel genes and functional characterization of TRPA1 in Spodoptera frugiperda
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作者 Yutong Zhang Hangwei Liu +3 位作者 Song Cao Bin Li Yang Liu Guirong Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1994-2005,共12页
Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory capabilities.Transient receptor potential(TRP)channels,which constitute a vast ion chann... Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory capabilities.Transient receptor potential(TRP)channels,which constitute a vast ion channel family,play pivotal roles in sensing the external environment and maintaining internal homeostasis in insects.TRP channels have been widely investigated for their critical roles in regulating various insect behaviors in recent years.In this study,we identified 15 TRP gene loci encoding 26 transcripts in the genome of S.frugiperda and analyzed their expression profiles at different developmental stages.The results revealed that S.frugiperda possesses four TRPC genes,six TRPA genes,one TRPM gene,two TRPV genes,one TRPN gene,and one TRPML gene,while a canonical TRPP is absent.Moreover,the SfruTRPA1 was functionally characterized using the Xenopus oocyte expression system.The results showed that SfruTRPA1 is activated by temperature increases from 20 to 45℃,and there is no significant desensitization after repeated stimuli within the same temperature range.Additionally,SfruTRPA1 is activated by certain natural chemicals,including allyl isothiocyanate(AITC)and cinnamaldehyde(CA).These findings provide valuable insights to the TRP genes in S.frugiperda. 展开更多
关键词 Spodoptera frugiperda transient receptor potential channel expression profile TRPA1 Xenopus oocyte
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Efficient Metal Recovery from Industrial Wastewater:Potential Oscillation and Turbulence Mode for Electrochemical System
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作者 Li Chen Gong Zhang +4 位作者 Huijuan Liu Shiyu Miao Qingbai Chen Huachun Lan Jiuhui Qu 《Engineering》 SCIE EI CAS CSCD 2024年第7期184-193,共10页
Efficient metal recovery from industrial wastewater facilitates addressing of the environmental hazards and resource requirements of heavy metals.The conventional electrodeposition recovery method is hampered by the l... Efficient metal recovery from industrial wastewater facilitates addressing of the environmental hazards and resource requirements of heavy metals.The conventional electrodeposition recovery method is hampered by the limitations of interfacial ion transport in charge-transfer reactions,creating challenges for simultaneous rapid and high-quality metal recovery.Therefore,we proposed integrating a transient electric field(TE)and swirling flow(SF)to synchronously enhance bulk mass transfer and promote interfacial ion transport.We investigated the effects of the operation mode,transient frequency,and flow rate on metal recovery,enabling determination of the optimal operating conditions for rapid and efficient sequential recovery of Cu in TE&SF mode.These conditions included low and high electric levels of 0 and 4 V,a 50%duty cycle,1 kHz frequency,and 400 L·h^(-1)flow rate.The kinetic coefficients of TE&SF electrodeposition were 3.5-4.3 and 1.37-1.97 times that of single TE and SF electrodeposition,respectively.Simulating the deposition process under TE and SF conditions confirmed the efficient concurrence of interfacial ion transport and charge transfer under TE and SF synergy,which achieved rapid and highquality metal recovery.Therefore,the combined deposition strategy is considered an effective technique for reducing metal pollution and promoting resource recycling. 展开更多
关键词 Ion transport Reaction kinetics transient electric field Swirling flow
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Time-dependent effects in transient liquid phase bonding of 304L and Cp-Ti using an Ag-Cu interlayer
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作者 Saeed VAZIRIAN Mohammad MOSHKBAR BAKHSHAYESH Ali FARZADI 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2237-2255,共19页
One of the challenges for bimetal manufacturing is the joining process.Hence,transient liquid phase(TLP)bonding was performed between 304L stainless steel and Cp-Ti using an Ag-Cu interlayer with a thickness of 75μm ... One of the challenges for bimetal manufacturing is the joining process.Hence,transient liquid phase(TLP)bonding was performed between 304L stainless steel and Cp-Ti using an Ag-Cu interlayer with a thickness of 75μm for bonding time of 20,40,60,and 90 min.The bonding temperature of 860℃ was considered,which is under the β transus temperature of Cp-Ti.During TLP bonding,various intermetallic compounds(IMCs),including Ti_(5)Cr_(7)Fe_(17),(Cr,Fe)_(2)Ti,Ti(Cu,Fe),Ti_(2)(Cu,Ag),and Ti_(2)Cu from 304L toward Cp-Ti formed in the joint.Also,on the one side,with the increase in time,further diffusion of elements decreases the blocky IMCs such as Ti_(5)Cr_(7)Fe_(17),(Cr,Fe)_(2)Ti,Ti(Cu,Fe)in the 304L diffusion-affected zone(DAZ)and reaction zone,and on the other side,Ti_(2)(Cu,Ag)IMC transformed into fine morphology toward Cp-Ti DAZ.The microhardness test also demonstrated that the(Cr,Fe)_(2)Ti+Ti_(5)Cr_(7)Fe_(17) IMCs in the DAZ on the side of 304L have a hardness value of HV 564,making it the hardest phase.The maximum and minimum shear strength values are equal to 78.84 and 29.0 MPa,respectively.The cleavage pattern dominated fracture surfaces due to the formation of brittle phases in dissimilar joints. 展开更多
关键词 diffusion brazing transient liquid phase bonding dissimilar material joints microstructural evolution mechanical properties grade 2 titanium
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