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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 191-200页

作者： LI Zhi-yu LI Kun CAI Jin-ming QIN Jian-fang ZHENG Zhao-wen School of Mathematical Sciences Qufu Normal UniversityQufu 273165China College of Mathematics and Systems Science Guangdong Polytechnic Normal UniversityGuangzhou 510665China

A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in this paper is based on Prufer transformation,which is different from the classical ones.Moreover,we give two examples to verify our main results.

关键词： Sturm-Liouville problem interface condition oscillatory solution

Effect of Low-Temperature Thermal Oxidation on the Capillary Performance of Sintered Copper Powder Wicks

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Journal of Thermal Science 2024年第1期33卷 29-40页

作者： ZHU Minghan FANG Runquan HU Yanxin ZHANG Jiangyun SHAO Dan HUANG Jin School of Material and Energy Guangdong University of TechnologyGuangzhou 510006China School of Electric Power Engineering Guangdong Polytechnic of Water Resources and Electric EngineeringGuangzhou 510006China Research into Artifacts Guangdong Key Laboratory of Battery SafetyGuangzhou Institute of Energy testingGuangzhou 511447China

In this study,a composite powder capillary wick is prepared,manufactured by sintering copper powder and surface treated by low-temperature thermal oxidation.It is used to improve the performance of the capillary wick.The forced flow method and infrared imaging method are used to test the permeability and capillary performance of the samples.The effects of different oxidation temperatures on the performance of capillary wick are investigated.The experimental results show that the wetting performance of the oxidized samples is significantly enhanced.With the increase of oxidation temperature,the permeability decreases.The capillary height and velocity of the thermally oxidized samples are significantly higher than those of the untreated capillary wick.However,the oxidation temperature needs to be adjusted to obtain the best capillary performance.The highest capillary performance is found at oxidation temperature of 300℃,with an increase of 46% compared to the untreated ones.Comparisons with other composite wicks show that the sample with an oxidation temperature of 300℃ has competitive capillary performance,making it a favorable alternative to two-phase heat transfer device.This study shows that combining low-temperature thermal oxidation technology with powder sintering is a convenient and effective method to improve the capillary performance of powder wicks.

关键词： low-temperature thermal oxidation capillary performance copper powder permeability

Controllable shaping of high-index dielectric nanoparticles by exploiting the giant optical force of femtosecond laser pulses

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Photonics Research 2024年第2期12卷 282-291页

作者： YUHENG MAO SHUWEN BAI MINGCHENG PANMAI LIDAN ZHOU SHIMEI LIU SHULEI LI HAIYING LIU HAIHUA FAN JUN DAI SHENG LAN guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices School of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China Shenzhen Institute of Terahertz Technology and Innovation Shenzhen 518102China State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510006China School of Optoelectronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou 510665China

Nanoparticles made of different materials usually support optical resonances in the visible to near infrared spectral range,such as the localized surface plasmons observed in metallic nanoparticles and the Mie resonances observed in dielectric ones.Such optical resonances,which are important for practical applications,depend strongly on the morphologies of nanoparticles.Laser irradiation is a simple but effective way to modify such optical resonances through the change in the morphology of a nanoparticle.Although laser-induced shaping of metallic nanoparticles has been successfully demonstrated,it remains a big challenge for dielectric nanoparticles due to their larger Young’s modulus and smaller thermal conductivities.Here,we proposed and demonstrated a strategy for realizing controllable shaping of high-index dielectric nanoparticles by exploiting the giant optical force induced by femtosecond laser pulses.It was found that both Si and Ge nanoparticles can be lit up by resonantly exciting the optical resonances with femtosecond laser pulses,leading to the luminescence burst when the laser power exceeds a threshold.In addition,the morphologies of Si and Ge nanoparticles can be modified by utilizing the giant absorption force exerted on them and the reduced Young’s modulus at high temperatures.The shape transformation from sphere to ellipsoid can be realized by laser irradiation,leading to the blueshifts of the optical resonances.It was found that Si and Ge nanoparticles were generally elongated along the direction parallel to the polarization of the laser light.Controllable shaping of Si and Ge can be achieved by deliberately adjusting the excitation wavelength and the laser power.Our findings are helpful for understanding the giant absorption force of femtosecond laser light and are useful for designing nanoscale photonic devices based on shaped highindex nanoparticles.

关键词： optical polarization dielectric

Analysis on unit maximum capacity of orthogonal multiple watermarking for multimedia signals in B5G wireless communications

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Digital Communications and Networks 2024年第1期10卷 38-44页

作者： Mianjie Li Senfeng Lai Jiao Wang Zhihong Tian Nadra Guizani Xiaojiang Du Chun Shan School of Electronics and Information Guangdong Polytechnic Normal UniversityGuangzhou510665China Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China Schoolof Electrical Engineering and Computer Science Washington State UniversityPullmanWA99164UsA Department of Computer and Information Science Temple UniversityPhiladelphiaPA19122USA

Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication space.Considering that intelligent applications to B5G wireless communications will involve security issues regarding user data and operational data,this paper analyzes the maximum capacity of the multi-watermarking method for multimedia signal hiding as a means of alleviating the information security problem of B5G.The multiwatermarking process employs spread transform dither modulation.During the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading vectors.Consequently,multiple watermarks can be simultaneously embedded into the same position of a multimedia signal.Moreover,the multiple watermarks can be extracted without affecting one another during the extraction process.We analyze the effect of the size of the spreading vector on the unit maximum capacity,and consequently derive the theoretical relationship between the size of the spreading vector and the unit maximum capacity.A number of experiments are conducted to determine the optimal parameter values for maximum robustness on the premise of high capacity and good imperceptibility.

关键词： B5G Multimedia information security Spread transform dither modulation Spreading vector measurement Unit maximum capacity

Revealing the key role of non-solvating diluents for fast-charging and low temperature Li-ion batteries

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Journal of Energy Chemistry 2024年第7期94卷 171-180页

作者： Yuping Zhang Siyin Li Junkai Shi Jiawei Lai Ziyue Zhuang Jingwen Liu Wenming Yang Liang Ma Yue-Peng Cai Jjian Xu Qifeng Zheng School of Chemistry Guangzhou Key Laboratory of Materials for Energy Conversion and StorageSouth China Normal UniversityGuangzhou 510006GuangdongChina guangzhou Foreign Language School Guangzhou 511455GuangdongChina Department of ChemistryCity University of Hong KongHong Kong 999077China

Fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based elec-trolytes due to their slow kinetics,narrow operating temperature and voltage range.Herein,an acetoni-trile(AN)-based localized high-concentration electrolyte(LHCE)is proposed to retain liquid state and high ionic conductivity at ultra-low temperatures while possessing high oxidation stability.We originally reveal the excellent thermal shielding effect of non-solvating diluent to prevent the aggregation of Lit sol-vates as temperature drops,maintaining the merits of fast Li transport and facile desolvation as at room temperature,which bestows the graphite electrode with remarkable low temperature performance(264 mA h g^(-1) at-20 C).Remarkably,an extremely high capacity retention of 97%is achieved for high-voltage high-energy graphitellNCM batteries after 250 cycles at-20 C,and a high capacity of 110 mA h g^(-1)(71%of its room-temperature capacity)is retained at-30°C.The study unveils the key role of the non-solvating diluents and provides instructive guidance in designing electrolytes towards fast-charging and low temperature LIBs.

关键词： Li-ion battery Fast-charging Low temperature Non-solvating diluent Shielding effect

Feasibility of low-intensity ultrasound treatment with hydroxylamine to accelerate the initiation of partial nitrification and allow operation under intermittent aeration

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Journal of Environmental Sciences 2024年第5期139卷 446-459页

作者： Jianxiong Jian Xiaojian Liao Zhihua Mo Shoupeng Li Lei Li Shaojin Chen Zhenhua Huang Junhao Chen Wencan Dai Shuiyu Sun guangzhou Key Laboratory Environmental Catalysis and Pollution Control Guangdong Key Laboratory of Environmental Catalysis and Health Risk ControlSchool of Environmental Science and EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China guangdong Province Solid Waste Recycling and Heavy Metal Pollution Control Engineering Technology Research Center Guangdong Polytechnic of Environmental Protection EngineeringFoshan 528216China Analysis and Test Center Guangdong University of TechnologyGuangzhou 510006China

Partial nitrification is a key aspect of efficient nitrogen removal,although practically it suf-fers from long start-up cycles and unstable long-term operational performance.To address these drawbacks,this study investigated the effect of low intensity ultrasound treatment combined with hydroxylamine(NH2OH)on the performance of partial nitrification.Results showthat compared with the control group,low-intensity ultrasound treatment(0.10W/mL,15 min)combined with NH2OH(5 mg/L)reduced the time required for partial nitrification initiation by 6 days,increasing the nitrite accumulation rate(NAR)and ammonia nitro-gen removal rate(NRR)by 20.4% and 6.7%,respectively,achieving 96.48% NRR.Mechanis-tic analysis showed that NH2OH enhanced ammonia oxidation,inhibited nitrite-oxidizing bacteria(NOB)activity and shortened the time required for partial nitrification initiation.Furthermore,ultrasonication combined with NH2OH dosing stimulated EPS(extracellular polymeric substances)secretion,increased carbonyl,hydroxyl and amine functional group abundances and enhanced mass transfer.In addition,16S rRNA gene sequencing results showed that ultrasonication-sensitive Nitrospira disappeared from the ultrasound+NH_(2)OH system,while Nitrosomonas gradually became the dominant group.Collectively,the results of this study provide valuable insight into the enhancement of partial nitrification start-up during the process of wastewater nitrogen removal.

关键词： Partial nitrification Low-intensity ultrasound Hydroxylamine Ammonia oxidizing bacteria Nitrite oxidizing bacteria

10 Gb/s classical secure key distribution based on temporal steganography and private chaotic phase scrambling

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Photonics Research 2024年第2期12卷 321-330页

作者： ZHENSEN GAO ZHITAO DENG LIHONG ZHANG XULIN GAO YUEHUA AN ANBANG WANG SONGNIAN FU ZHAOHUI LI YUNCAI WANG YUWEN QIN School of Information Engineering Guangdong University of TechnologyGuangzhou 510006China Pengcheng Laboratory Shenzhen 518062China Key Laboratory of Photonic Technology for Integrated Communication and Sensing Ministry of EducationGuangzhou 510006China School of Optoelectronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou 510665China School of Electrical and Information Technology Sun Yat-sen UniversityGuangzhou 510006China

Secure distribution of high-speed digital encryption/decryption keys over a classical fiber channel is strongly pursued for realizing perfect secrecy communication systems.However,it is still challenging to achieve a secret key rate in the order of tens of gigabits per second to be comparable with the bit rate of commercial fiber-optic systems.In this paper,we propose and experimentally demonstrate a novel solution for high-speed secure key distribution based on temporal steganography and private chaotic phase scrambling in the classical physical layer.The encryption key is temporally concealed into the background noise in the time domain and randomly phase scrambled bit-by-bit by a private chaotic signal,which provides two layers of enhanced security to guarantee the privacy of key distribution while providing a high secret key rate.We experimentally achieved a record classical secret key rate of 10 Gb/s with a bit error rate lower than the hard-decision forward error correction(HD-FEC)over a 40 km standard single mode fiber.The proposed solution holds great promise for achieving high-speed key distribution in the classical fiber channel by combining steganographic transmission and chaotic scrambling.

关键词： chaotic distribution phase

Deep Broad Learning for Emotion Classification in Textual Conversations

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Tsinghua Science and Technology 2024年第2期29卷 481-491页

作者： Sancheng Peng Rong Zeng Hongzhan Liu Lihong Cao Guojun Wang Jianguo Xie Center for Linguistics and Applied Linguistics and Laboratory of Language Engineering and ComputingGuangdong University of Foreign StudiesGuangzhou 510006China guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices South China Normal UniversityGuangzhou 510006China School of Computer Science and Cyber Engineering Guangzhou UniversityGuangzhou 510006China Modern Education Technology Center Guangdong University of Foreign StudiesGuangzhou 510006China

Emotion classification in textual conversations focuses on classifying the emotion of each utterance from textual conversations.It is becoming one of the most important tasks for natural language processing in recent years.However,it is a challenging task for machines to conduct emotion classification in textual conversations because emotions rely heavily on textual context.To address the challenge,we propose a method to classify emotion in textual conversations,by integrating the advantages of deep learning and broad learning,namely DBL.It aims to provide a more effective solution to capture local contextual information(i.e.,utterance-level)in an utterance,as well as global contextual information(i.e.,speaker-level)in a conversation,based on Convolutional Neural Network(CNN),Bidirectional Long Short-Term Memory(Bi-LSTM),and broad learning.Extensive experiments have been conducted on three public textual conversation datasets,which show that the context in both utterance-level and speaker-level is consistently beneficial to the performance of emotion classification.In addition,the results show that our proposed method outperforms the baseline methods on most of the testing datasets in weighted-average F1.

关键词： emotion classification textual conversation Convolutional Neural Network(CNN) Bidirectional Long Short-Term Memory(Bi-LSTM) broad learning

The appearance of cytoplasmic cytochrome C precedes apoptosis during Drosophila salivary gland degradation

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Insect Science 2024年第1期31卷 157-172页

作者： Shihui Long Wenxin Cao Yongyu Qiu Ruohan Deng Jiali Liu Lidan Zhang Renke Dong Fengxin Liu Sheng Li Haigang Zhao Na Li Kang Li guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural UniversityGuangzhouChina Guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouGuangdong ProvinceChina School of Food Science and Engineering South China University of TechnologyGuangzhouChina ChemPartner PharmaTech Co. LtdJiangmenGuangdong ProvinceChina

Apoptosis is an important process for organism development that functions to eliminate cell damage,maintain homeostasis,and remove obsolete tissues during morphogenesis.In mammals,apoptosis is accompanied by the release of cytochrome C(Cyt-c)from mitochondria to the cytoplasm.However,whether this process is conserved in the fruit fly,Drosophila melanogaster,remains controversial.In this study,we discovered that during the degradation of Drosophila salivary gland,the transcription of mitochondria apoptosis factors(MAPFs),Cyt-c,and death-associated APAF1-related killer(Dark)encoding genes are all upregulated antecedent to initiator and effector caspases encoding genes.The proteins Cyt-c and the active caspase 3 appear gradually in the cytoplasm during salivary gland degradation.Meanwhile,the Cyt-c protein colocates with mito-GFP,the marker indicating cytoplasmic mitochondria,and the change in mitochondrial membrane potential coincides with the appearance of Cyt-c in the cytoplasm.Moreover,impeding or promoting 20E-induced transcription factor E93 suppresses or enhances the staining of Cyt-c and the active caspase 3 in the cytoplasm of salivary gland,and accordingly decreases or increases the mitochondrial membrane potential,respectively.Our research provides evidence that cytoplasmic Cyt-c appears before apoptosis during Drosophila salivary gland degradation,shedding light on partial conserved mechanism in apoptosis between insects and mammals.

关键词： active caspase 3 apoptosis Cyt-c Drosophila salivary gland

Effectiveness of fecal DNA syndecan-2 methylation testing for detection of colorectal cancer in a high-risk Chinese population

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1361-1373页

作者： Wen-Feng Luo Yu-Ting Jiao Xiao-Ling Lin Ying Zhao Sheng-Bo Wang Jian Shen Jie Deng Yu-Feng Ye Ze-Ping Han Fang-Mei Xie Jin-Hua He Yu Wan Central Laboratory of Panyu Central Hospital Guangzhou Panyu Central HospitalGuangzhou 511400Guangdong ProvinceChina South China normal university-Panyu Central Hospital Joint Laboratory of Translational Medical Research Guangzhou Panyu Central HospitalGuangzhou 511400Guangdong ProvinceChina Digestive Disease Center Guangzhou Panyu Central HospitalGuangzhou 511400Guangdong ProvinceChina Shunde Vocational and Technical College Foshan 528300Guangdong ProvinceChina Medical Imaging Institute of Panyu Guangzhou Panyu Central HospitalGuangzhou 511400Guangdong ProvinceChina

BACKGROUND Colorectal cancer(CRC)is among the most prevalent and life-threatening malignancies worldwide.Syndecan-2 methylation(mSDC2)testing has emerged as a widely used biomarker for early detection of CRC in stool and serum samples.Cancer(CRC)is among the most prevalent and life-threatening malignancies worldwide.mSDC2 testing has emerged as a widely used biomarker for early detection of CRC in stool and serum samples.AIM To validate the effectiveness of fecal DNA mSDC2 testing in the detection of CRC among a high-risk Chinese population to provide evidence-based data for the development of diagnostic and/or screening guidelines for CRC in China.METHODS A high-risk Chinese cohort consisting of 1130 individuals aged 40-79 years was selected for evaluation via fecal mSDC2 testing.Sensitivity and specificity for CRC,advanced adenoma(AA)and advanced colorectal neoplasia(ACN)were determined.High-risk factors for the incidence of colorectal lesions were determined and a logistic regression model was constructed to reflect the efficacy of the test.RESULTS A total of 1035 high-risk individuals were included in this study according to established criteria.Among them,16 suffered from CRC(1.55%),65 from AA(6.28%)and 189 from non-AAs(18.26%);150 patients were diagnosed with polyps(14.49%).Diagnoses were established based upon colonoscopic and pathological examinations.Sensitivities of the mSDC2 test for CRC and AA were 87.50%and 40.00%,respectively;specificities were 95.61%for other groups.Positive predictive values of the mSDC2 test for CRC,AA and ACN were 16.09%,29.89%and 45.98%,respectively;the negative predictive value for CRC was 99.79%.After adjusting for other high-risk covariates,mSDC2 test positivity was found to be a significant risk factor for the occurrence of ACN(P<0.001).CONCLUSION Our findings confirmed that offering fecal mSDC2 testing and colonoscopy in combination for CRC screening is effective for earlier detection of malignant colorectal lesions in a high-risk Chinese population.

关键词： Colorectal cancer Syndecan-2 DNA methylation Chinese population