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Journal of Thermal Science 2019年第3期28卷 571-584页

作者： han wanlong WANG Yueming FENG Zhenping LI Hongzhi YAO Mingyu ZhanG Yifan R&D Center Xi'an Thermal Power Research Institute Co. Ltd. School of Energy and Power Engineering Xi'an Jiaotong University

In order to further understand the aerothermodynamic performance and flow loss mechanism of SCO_2 turbines, RANS equations and an SST Turbulence Model were chosen for a numerical study on the secondary flow and vortex structure of cascades using the commercial software CFX. The dimensionless vorticity analysis method was used to study the flow characteristics of the logarithmic layer and viscous sublayer in high pressure guide vane cascades. The new vortex structure and formation mechanism of the vortices were given and analyzed. Simulation results indicated that during the motion of the boundary layer in the cascades, the logarithmic layer and viscous sublayer obtain the different rotational direction vorticity, respectively. The endwall logarithmic layer and pressure side leg of the horseshoe votex gradually develop into the passage vortex, with the endwall viscous sublayer gradually developing into the corner viscous sublayer vortex II and the endwall viscous sublayer vortex I. The endwall viscous sublayer that rolled by the passage vortex is encountered with the upstream-side and radial boundary layer of the vane at the suction separation line, forming the suction separation line vortex beside the passage vortex. A pair of radial transition vortices are formed between the wake and the main stream.

关键词： SCO2 turbine vortex structure dimensionless vorticity logarithmic layer viscous sublayer secondary flow

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新型风力/洋流涡轮气动及引射特性

哈尔滨工业大学学报 2016年第1期48卷 21-28页

作者：韩万龙颜培刚何玉荣韩万金哈尔滨工业大学能源科学与工程学院哈尔滨150001

为高效开发利用低品位风能和洋流能,采用涡扇发动机喷管引射技术,设计含有单级涡轮和波瓣引射器结构的低品位风力/洋流涡轮,给出一种波瓣引射器的参数化方法,并基于CFX软件RANS方程和k-ε湍流模型数值研究涡轮气动和引射特性.结果表明... 详细信息

为高效开发利用低品位风能和洋流能,采用涡扇发动机喷管引射技术,设计含有单级涡轮和波瓣引射器结构的低品位风力/洋流涡轮,给出一种波瓣引射器的参数化方法,并基于CFX软件RANS方程和k-ε湍流模型数值研究涡轮气动和引射特性.结果表明：含单级涡轮和波瓣引射器结构的低品位风力/洋流涡轮可将其转子四周流过的能量通过波瓣引射器引入涡轮后侧,通过流向涡和正交涡共同产生的抽吸作用,降低涡轮转子后侧被压,使有效做功速度增大约1.4倍,等效于提升了能量的品位.在2~6 m/s的风能和2~4 m/s的洋流能利用方面,含单级涡轮和波瓣引射器结构的风力/洋流涡轮功率曲线与来流速度成指数增长,流通能力增大32.70%~35.33%,在低速工况能量利用率可达66%~77%.

关键词：波瓣引射器洋流能风能有效做功速度引射能力

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非均匀加热管内超临界CO2传热特性研究

热力发电 2019年第11期48卷 22-29页

作者：吴家荣李红智杨玉韩万龙西安热工研究院有限公司

在质量流速100 kg/(m^2·s),热流密度28~50 kW/m^2,入口压力7.6~8.6 MPa下,对超临界CO2在非均匀热流密度下竖直向上的流动传热规律进行了数值模拟,比较了均匀与非均匀加热的区别,分析了非均匀加热情况下热流密度和入口压力对对流传热系... 详细信息

在质量流速100 kg/(m^2·s),热流密度28~50 kW/m^2,入口压力7.6~8.6 MPa下,对超临界CO2在非均匀热流密度下竖直向上的流动传热规律进行了数值模拟,比较了均匀与非均匀加热的区别,分析了非均匀加热情况下热流密度和入口压力对对流传热系数、浮力效应和加速效应的影响,提出并检验了新的传热关联式。结果表明:与均匀加热相比,非均匀加热局部对流传热系数小,壁温更高;随着热流密度的增大,对流传热系数减小,浮力效应和加速效应增强;高热流密度下,随着入口压力的增大,对流传热系数增大,浮力效应和加速效应减弱;新的传热关联式能较好地预测本文中超临界CO2的传热规律。

关键词：超临界CO2 非均匀加热管对流传热系数浮力效应加速效应热流密度壁温压力

Recent advances in exploring new blood-based biomarkers for the early diagnosis of gastric cancer

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Science China Chemistry 2025年第1期68卷 35-45页

作者： Xinyu Peng Qian Ma Da han School of Life Science Shanghai University Institute of Molecular Medicine Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine State Key Laboratory of Oncogenes and Related Genes Renji Hospital School of Medicine Shanghai Jiao Tong University Department of Research and Development Intellinosis Biotechnologies Co.Ltd.

Gastric cancer(GC) is a prevalent and lethal malignancy worldwide, and the 5-year survival rate is less than 30%. The absence of distinctive symptoms often leads to late-stage diagnosis, contributing to a grim prognosis. Early detection is pivotal for improving the survival rates and outcomes of GC patients. Traditional diagnostic methods, including gastroscopy and histopathological examination, are restricted in the early diagnosis of GC. Conventional protein biomarkers, such as carcinoembryonic antigen(CEA), carbohydrate antigen 19-9(CA19-9), and carbohydrate antigen 72-4(CA72-4), exhibit insufficient sensitivity and specificity for GC screening, which diminishes their clinical value. Recently, novel circulating biomarkers, such as circulating tumor cells(CTCs), circulating tumor cell DNA(ct DNA), and circulating free RNA(cf RNA), have emerged as promising candidates in the burgeoning field of liquid biopsy due to their superior sensitivity and specificity. This review focuses on the latest research on blood-based biomarkers for GC diagnosis and examines the clinical potentials and challenges associated with these emerging biomarkers.

关键词： gastric cancer early diagnosis blood

Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG Xiaofeng TAO Shujun han Huici WU Kai YANG Zhu han National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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利用BP人工神经网络预测天然气中重组分对净化装置的影响

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石油与天然气化工 2018年第6期47卷 1-6页

作者：韩万龙范峥薛岗王文珍刘子兵葛涛西安长庆科技工程有限责任公司西安石油大学化学化工学院

由于天然气中的重组分会对脱硫装置的运行效果及产品气气质造成影响,这一实际生产问题需要得到有效的解决。在MDEA溶液吸收性能评价装置上测定了不同条件下的MDEA溶液吸收性能,系统地研究了不同重组分对MDEA溶液吸收性能的作用规律,采... 详细信息

由于天然气中的重组分会对脱硫装置的运行效果及产品气气质造成影响,这一实际生产问题需要得到有效的解决。在MDEA溶液吸收性能评价装置上测定了不同条件下的MDEA溶液吸收性能,系统地研究了不同重组分对MDEA溶液吸收性能的作用规律,采用多因素方差分析筛选了关键因素,以判定其影响程度的大小,并采用人工神经网络建立了天然气中重组分不利影响的预测模型。结果表明:天然气中的重组分i-C_5、C_6、C_7、C_8和C_(10)对MDEA溶液吸收能力具有十分显著的影响,它们均属于BP神经网络预测模型的有效输入信号,模型预测值与真实值较为近似,BP人工神经网络表现出良好的准确性和稳定性。因此,利用BP人工神经网络能够准确、可靠地预测天然气中重组分对MDEA溶液吸收性能的不利影响。

关键词：天然气脱硫多因素方差分析 BP人工神经网络

Improvement of Cold Recycled Mixture Performance Based on Improved Density Test Method and RAP Characteristics

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 79-87页

作者： han Zhanchuang PANG Yafeng LIN Hongwei China First Highway Engineering Group Co. LtdBeijing 100024China The Key Laboratory of Road and Traffic Engineering Ministry of EducationTongji UniversityShanghai 201804China Guangzhou Baiyun International Airport Co. Ltd.Guangzhou 510470China

The available test methods for optimal moisture content of cold recycled mixture(CRM)as well as its bulk specific gravity,and theoretical maximum relative density were analyzed in this *** test improvements were suggested to improve test control of the CRM road performance based on the discovered ***,the properties of reclaimed asphalt pavement(RAP),including the content of old asphalt,penetration index,passing rate of 4.75 mm sieve,and gradation change rate after extraction,were *** effects of RAP characteristics on splitting tensile strength,water stability,the high-and low-temperature performance of emulsified asphalt CRM were *** results show that the optimum moisture content of CRM should be determined when the compaction work matches the specimen’s molding *** the analyzed methods of bulk specific gravity assessment,the dry-surface and CoreLok methods provide more robust and accurate results than the wax-sealing method,while the dry-surface method is the most *** modified theoretical maximum relative density test method is proposed,which can reduce the systematic error of the vacuum test *** following RAP-CRM trends can be *** lower the content of old asphalt and the smaller the change rate of gradation,the smaller the voids and the better the water stability of *** greater the penetration of old asphalt,the higher the fracture work and low-temperature splitting *** greater the penetration,the higher the passing rate of 4.75 mm sieve after extraction,and the worse the high-temperature performance of CRM.

关键词： RAP volume parameters high-temperature performance low-temperature performance water stability

Crystallization Modulation and Holistic Passivation Enables Efficient Two‑Terminal Perovskite/CuIn(Ga)Se_(2)Tandem Solar Cells

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Nano-Micro Letters 2025年第1期17卷 205-215页

作者： Cong Geng Kuanxiang Zhang Changhua Wang Chung Hsien Wu Jiwen Jiang Fei Long Liyuan han Qifeng han Yi‑Bing Cheng Yong Peng State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People’s Republic of China Triumph Photovoltaic Materials Co. Ltd.No.1001 Yannan AvenueHigh‑Tech Development DistrictBengbuAnhui 233000People’s Republic of China College of Materials Science and Engineering Guilin University of TechnologyGuilin 541004People’s Republic of China State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)***,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device *** this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK *** addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain ***,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing *** a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our *** validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells.

关键词： PVK/CIGS TSCs Irregular rough surfaces Modulating the growth PVK/C60 interface recombination

Unmasking Social Robots’Camouflage:A GNN-Random Forest Framework for Enhanced Detection

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Computers, Materials & Continua 2025年第1期82卷 467-483页

作者： Weijian Fan Chunhua Wang Xiao han Chichen Lin School of Data Science and Intelligent Media Communication University of ChinaBeijing100024China School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China Institute of Communication Studies Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

The proliferation of robot accounts on social media platforms has posed a significant negative impact,necessitating robust measures to counter network anomalies and safeguard content *** robot detection has emerged as a pivotal yet intricate task,aimed at mitigating the dissemination of misleading *** graphbased approaches have attained remarkable performance in this realm,they grapple with a fundamental limitation:the homogeneity assumption in graph convolution allows social robots to stealthily evade detection by mingling with genuine human *** unravel this challenge and thwart the camouflage tactics,this work proposed an innovative social robot detection framework based on enhanced HOmogeneity and Random Forest(HORFBot).At the core of HORFBot lies a homogeneous graph enhancement strategy,intricately woven with edge-removal techniques,tometiculously dissect the graph intomultiple revealing ***,leveraging the power of contrastive learning,the proposed methodology meticulously trains multiple graph convolutional networks,each honed to discern nuances within these tailored *** culminating stage involves the fusion of these feature-rich base classifiers,harmoniously aggregating their insights to produce a comprehensive detection *** experiments on three social robot detection datasets have shown that this method effectively improves the accuracy of social robot detection and outperforms comparative methods.

关键词： Social robot detection graph neural networks random forest homophily heterophily

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang han Jia Tuo Liu Yuzhen Yang Jun Yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter