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Science China(Physics,Mechanics & Astronomy) 2018年第1期61卷 51-56页

作者： ShenDong Zhuang yan Chen WeiChao zhang zhuo Chen ZhenLin Wang School of Physics and National Laboratory of Solid State Microstructures Nanjing University College of Engineering and Applied Sciences Nanjing University

We report on the experimental realization of a graphene quantum dots （GQD）-based htunidity sensor and ultraviolet （UV） photodetector. We demonstrate that the conductance of the GQD increases linearly with increasing relative humidity （RH） of the surrounding environment due to the carrier trapping effect, which forms the basis of a humidity sensor. When the sensor is operated in the dark state, the sensitivity can reach as high as 0.48 nS RH-^1. The GQD are also found to exhibit light intensity dependent negative photoconductivity under the UV irradiation, which can be exploited for UV detection. As a result of these carrier trapping and de-trapping processes, the performance of the photodetector can be significantly improved with the increasing RH, and the photoresponsivity can reach a high value of-418.1 μA W^-1 in the high humid state of RH=90%.

关键词： graphene quantum dots carrier trapping effect negative photoconductivity

Electro-optic tuning in ferroelectric capacitor with photonic crystal nanobeam cavity

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Science China(Information Sciences) 2025年

作者： Tongtong WANG Yong zhang Danyang YAO Zhi JIANG Dongxin TAN Jie WEN Qiyu yanG Xuetao GAN yan LIU Yue HAO Genquan HAN State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian University Key Laboratory of Light Field Manipulation and Information Acquisition Ministry of Industry and Information TechnologyShaanxi Key Laboratory of Optical Information Technology School of Physical Science and TechnologyNorthwestern Polytechnical University Hangzhou Institute of Technology Xidian University

Silicon photonics has provided a platform for the convergency of photonic devices and electronic circuits, facilitating the development of optical telecommunications and optical interconnects on chip[1]. As the basic building block of optical communication systems, electro-optic tuning is expected to be more compact, high bandwidth, energy efficient, and allow for CMOS-compatible fabrication in the future[2]. Resonator-based electro-optic tuning has attracted more and more interest due to the small footprint, enhanced light-matter interactions and high energy efficiency. Compared with microring and microdisk resonators, photonic crystal nanobeam cavities （PCNBCs） realize higher quality factors, stronger light-matter interactions, ultrasmall mode volume and a much larger free spectral range （FSR）[3].

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Razumikhin Type Boundedness Theorems in Terms of Two Measures for Impulsive Integro-differential Systems

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 1007-1016页

作者： zhuo-ying L yan-Lin ZHENG Lai-liang zhang Depart of Common Courses Shandong University of Science and Technology Faculty of Science Shandong University of Science and Technology

Some new direct criteria of boundedness in terms of two measures for impulsive integro-differential systems with fixed moments of impulse effects are established by Lyapunov functions coupled with Razumikhin techniques.

关键词： impulsive integro-differential system Lyapunov function boundedness in terms of two measures

Extraction of vanadium from vanadium slag by high pressure oxidative acid leaching

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International Journal of Minerals,Metallurgy and Materials 2015年第1期22卷 21-26页

作者： Guo-quan zhang Ting-an zhang Guo-zhi Lü Ying zhang yan Liu zhuo-lin Liu Key Laboratory of Ecological Utilization of Multi-Metal Intergrown Ores of the Ministry of Education School of Materials and MetallurgyNortheastern University

To extract vanadium in an environment friendly manner, this study focuses on the process of leaching vanadium from vanadium slag by high pressure oxidative acid leaching. Characterizations of the raw slag, mineralogy transformation, and the form of leach residues were made by X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The result shows that the vana-dium slag is composed of major phases of fayalite, titanomagnetite, and spinel. During the high pressure oxidative acid leaching process, the fayalite and spinel phases are gradually decomposed by sulfuric acid, causing the release of vanadium and iron in the solution. Meanwhile, unreacted silicon and titanium are enriched in the leach residues. With the initial concentration of sulfuric acid at 250 g·L^-1, a leaching tem-perature of 140℃, a leaching time of 50 min, a liquid-solid ratio of 10：1 mL·g^-1, and oxygen pressure at 0.2 MPa, the leaching rate of vana-dium reaches 97.69%.

关键词： extraction vanadium slag pressure leaching sulfuric acid mineralogy

基于重叠社区划分和非回溯矩阵的社交网络多源点检测

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计算机工程与应用 2025年第1期61卷 300-307页

作者：刘岗王炎张雪芹华东理工大学信息科学与工程学院上海200237 上海市计算机软件评测重点实验室上海201112

在线社交网络的发展为信息传播提供了极大的便利,但同时在一定程度上也成为谣言等信息的重要传播渠道。社交网络的信息源检测对于控制信息的传播起着重要作用。为了解决现有社交网络多源点检测方法准确度不够高的问题,提出了一种新颖的... 详细信息

在线社交网络的发展为信息传播提供了极大的便利,但同时在一定程度上也成为谣言等信息的重要传播渠道。社交网络的信息源检测对于控制信息的传播起着重要作用。为了解决现有社交网络多源点检测方法准确度不够高的问题,提出了一种新颖的多源点同步检测方法SVT-BiasMSI。该方法将多源检测问题转化为若干单源检测问题,采用局部度中心节点及相邻节点的Jaccard系数选取种子节点,使用Voronoi方法对社交网络进行初步社区划分,通过tolerance neighborhood方法寻找分区之间重叠部分的节点并实现重叠社区划分,为了兼顾网络全局和局部信息,基于传染邻域偏差改进非回溯矩阵多源点检测方法,提高单源点检测精度。在多个社交网络数据集中的实验表明,所提的方法能够有效提高在线社交网络多源点检测和定位准确度。

关键词：社交网络多源检测重叠社区划分非回溯矩阵传染邻域偏值

Combining neural network-based method with heuristic policy for optimal task scheduling in hierarchical edge cloud

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Digital Communications and Networks 2023年第3期9卷 688-697页

作者： zhuo Chen Peihong Wei yan Li College of Computer Science and Engineering Chongqing University of TechnologyChongqing200433China School of Artificial Intelligence Chongqing University of TechnologyChongqing200433China

Deploying service nodes hierarchically at the edge of the network can effectively improve the service quality of offloaded task requests and increase the utilization of *** this paper,we study the task scheduling problem in the hierarchically deployed edge *** first formulate the minimization of the service time of scheduled tasks in edge cloud as a combinatorial optimization problem,blue and then prove the NP-hardness of the *** from the existing work that mostly designs heuristic approximation-based algorithms or policies to make scheduling decision,we propose a newly designed scheduling policy,named Joint Neural Network and Heuristic Scheduling(JNNHSP),which combines a neural network-based method with a heuristic based *** takes the Sequence-to-Sequence(Seq2Seq)model trained by Reinforcement Learning(RL)as the primary policy and adopts the heuristic algorithm as the auxiliary policy to obtain the scheduling solution,thereby achieving a good balance between the quality and the efficiency of the scheduling ***-depth experiments show that compared with a variety of related policies and optimization solvers,JNNHSP can achieve better performance in terms of scheduling error ratio,the degree to which the policy is affected by re-sources limitations,average service latency,and execution efficiency in a typical hierarchical edge cloud.

关键词： Edge cloud Task scheduling Neural network Reinforcement learning

Adaptability of n-γdiscrimination and filtering methods based on plastic scintillation

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Nuclear Science and Techniques 2021年第3期32卷 63-71页

作者： zhuo Zuo Hao-Ran Liu Yu-Cheng yan Bing-Qi Liu Song zhang Chengdu University of Technology College of Engineering Technology Leshan 614000SichuanChina Southwest Institute of Physics Chengdu 610225China Chengdu University Chengdu 610106China Chengdu University of Technology Chengdu 610225China

Neutrons have been extensively used in many fields,such as nuclear physics,biology,geology,medical science,and national defense,owing to their unique penetration *** rays are usually accompanied by the detection of *** capability to discriminate neutrons from gamma rays is important for evaluating plastic scintillator neutron detectors because similar pulse shapes are generated from both forms of radiation in the detection *** pulse signals measured by plastic scintillators contain noise,which decreases the accuracy of n-y *** improve the performance of n-y discrimination,the noise of the pulse signals should be filtered before the n-y discrimination *** this study,the influences of the Fourier transform,wavelet transform,moving-average filter,and Kalman algorithm on the charge comparison method,fractal spectrum method,and back-propagation neural network methods were *** was found that the Fourier transform filtering algorithm exhibits better adaptability to the charge comparison method than others,with an increasing accuracy of 6.87%compared to that without the filtering ***,the Kalman filter offers an improvement of 3.04%over the fractal spectrum method,and the adaptability of the moving-average filter in backpropagation neural network discrimination is better than that in other methods,with an increase in 8.48%.The Kalman filtering algorithm has a significant impact on the peak value of the pulse,reaching 4.49%,and it has an insignificant impact on the energy resolution of the spectrum measurement after discrimination.

关键词： Fourier transform Wavelet transform Moving average Kalman filter Charge comparison method Fractal spectrum method Back-propagation neural network

Pressure leaching of converter vanadium slag with waste titanium dioxide

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Rare Metals 2016年第7期35卷 576-580页

作者： Guo-Quan zhang Ting-An zhang Ying zhang Guo-Zhi Lv yan Liu zhuo-Lin Liu Key Laboratory of Ecological Utilization of Multi-Metal Intergrown Ores of Ministry of Education School of Materials and MetallurgyNortheastern University

The process of pressure leaching the converter vanadium slag with waste titanium dioxide without roasting was studied. Mineralogy analysis indicates that the con- verter vanadium slag contains mainly three mineral phases： magnetite, titanium magnetite, and silicate phase. Vana- dium is in combination with iron, titanium, manganese, aluminum, and silicon. The impacts of leaching tempera- ture, leaching time, stirring speed, liquid-to-solid ratio, and initial leaching agent concentration were investigated on the waste titanium dioxide leaching process. The results indi- cate that under the optimal conditions, the vanadium and the iron leaching rates are 96.85 % and 93.50 %, respectively, and the content of titanium is 12.6 % in the residue. The main mineral phases for the residues under the optimal operation conditions are quartz, ilmenite, anatase, and sili- cate phase, and the residues can be reused as the extraction of titanium raw materials for titanium dioxide production technology by the sulfate method.

关键词： Vanadium Waste titanium dioxide Pressure leaching Resource utilization

Value of contrast-enhanced ultrasound combined with elastography in evaluating cervical lymph node metastasis in papillary thyroid carcinoma

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World Journal of Clinical Cases 2019年第1期7卷 49-57页

作者： Wei Jiang Hong-yan Wei Hai-yan zhang Qiu-Luan zhuo Department of Ultrasound Shenzhen Nanshan District People’s Hospital

BACKGROUND Cervical lymph node metastasis in papillary thyroid carcinoma(PTC) affects the treatment and prognosis of patients. Ultrasound is a common imaging method for detecting cervical lymph nodes in PTC patients; however, it is not accurate in determining lymph node *** To evaluate the value of contrast-enhanced ultrasound combined with elastography in evaluating cervical lymph node metastasis in *** A total of 94 patients with PTC were recruited. According to pathological results,lymph nodes were divided into two groups: metastatic group(n = 50) and reactive group(n = 63). The routine ultrasound findings, contrast-enhanced ultrasound and elastography data were recorded and compared. Logistic regression was used to generate predictive probability distributions for the diagnosis of lymph node metastasis with different indicators. Receiver operating characteristic curve analysis was used to test the efficacy of contrast-enhanced ultrasound combined with elastography based on routine ultrasound in evaluating PTC cervical lymph node *** The ratio of long diameter/short diameter(L/S) ≤ 2, irregular marginal morphology, missing lymphatic portal, peripheral or mixed blood flow distribution, peak intensity(PI), non-uniform contrast distribution and elasticity score in the metastatic group were significantly higher than those in the reactive group(P < 0.05). L/S ratio, missing lymphatic portal, PI and elasticity score had a significant influence on the occurrence of PTC cervical lymph node metastasis(P< 0.05). Furthermore, the area under the curve(AUC) for lymph node metastasis diagnosed using the combination of PI ratio, elasticity score, missing lymphatic portal and LS was 0.936, which was significantly higher than the AUC for PI ratio alone. The difference was statistically significant(P < 0.05). The fitting equation for the combined diagnosis was logit(P) =-12.341 + 1.482 × L/S ratio + 3.529 ×missing lymphatic portal + 0.392 × PI + 3

关键词： Contrast-enhanced ultrasound Elastography Papillary thyroid cancer Cervical lymph node metastasis

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密度对谷物混合颗粒分层影响的分析

农机化研究 2025年第4期47卷 35-41,49页

作者：张妍王子谦张延胡欣宇赵湛江苏大学农业工程学院江苏镇江212013

采用离散元模拟了垂直振动下具有相同尺寸、不同密度的谷物混合颗粒分层过程,结果表明:小密度颗粒倾向于向上运动形成单一颗粒层,而大密度颗粒与部分小密度颗粒停留在单一颗粒层下,组成混合状态。为此,提出相应评价指标,定量描述混合物... 详细信息

采用离散元模拟了垂直振动下具有相同尺寸、不同密度的谷物混合颗粒分层过程,结果表明:小密度颗粒倾向于向上运动形成单一颗粒层,而大密度颗粒与部分小密度颗粒停留在单一颗粒层下,组成混合状态。为此,提出相应评价指标,定量描述混合物分层程度,并讨论了混合颗粒密度比对分层速度的影响。结合混合物分层中空隙填充及动能理论,分析了密度影响分层机理,结果表明:在不同密度谷物混合颗粒分层过程中,随密度比增加小密度颗粒组成的单一颗粒层厚度增加并趋于饱和;混合层占总层数比率随密度比增加而减少并趋于稳定;颗粒分层速度随着密度比增加而增加,当密度比大于10时密度比对分层速度影响减弱;在混合物分层过程中,大密度颗粒较为活跃,且动能大于小密度颗粒的动能。

关键词：谷物颗粒分层密度数值模拟离散元法

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