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Journal of Environmental Sciences 2024年第3期137卷 224-236页

作者： Zhexin Zhu Wenjie Qian Zhiguo Shang Xiaoji Ma Zhendong wang wangyang Lu Wenxing Chen National Engineering Lab for Textile Fiber Materials and Processing Technology(Zhejiang) Zhejiang Sci-Tech UniversityHangzhou 310018China

The monoaminotrinitro iron phthalocyanine(FeMATNPc)is used to connect with isonicotinic acid(INA)for amide bonding and axial coordination to synthetic a unique catalyst FeMATNPc-INA,which is loaded in polyacrylonitrile(PAN)nanofibers by *** introduction of INA destroys theπ-πconjugated stack structure in phthalocyanine molecules and exposes more active *** FeMATNPc-INA structure is characterized by X-ray photoelectron spectroscopy and UV-visible absorption spectrum,and the FeMATNPcINA/PAN structure is characterized by Fourier transform infrared spectroscopy and X-ray *** FeMATNPc-INA/PAN can effectively activate peroxymonosulfate(PMS)to eliminate carbamazepine(CBZ)within 40 minutes(PMS 1.5 mmol/L)in the *** effects of catalyst dosage,PMS concentration,pH and inorganic anion on the degradation of CBZ are *** has been confirmed by electron paramagnetic resonance,gas chromatography–mass spectroscopy and free radical capture experiments that the catalytic system is degraded by·OH,SO4^(·-)and Fe(IV)=O are the major active species,the singlet oxygen(^(1)O_(2))is the secondary active *** degradation process of CBZ is analyzed by ultra-high performance liquid chromatography-mass spectrometry and the aromatic compounds have been degraded to small molecular acids.

关键词： Pyridine bridged iron phthalocyanine Isonicotinic chloride hydrochloride Efficient elimination Peroxymonosulfate activation Degradation pathway

A Compact Filtering Antenna System with Wide-Angle Scanning Capability for V2I Communication

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Chinese Journal of Electronics 2024年第2期33卷 516-526页

作者： Chuang HAN Tong LI Zhaolin ZHANG Ling wang Guangwei YANG School of Electronics and Information Northwestern Polytechnical University School of Electronic Engineering and Computer Science Queen Mary University of London

A compact filtering antenna system with wide-angle scanning is proposed for vehicle to infrastructure(V2I) communication which would handle complex communication scenarios. In this work, a wide beam filtering antenna is realized by using some inductive resistance structures such as metal pins and pillars, and capacitive structures such as slots, parasitical patches to produce the radiation nulls at two sides of the operating frequency band and improve the impedance matching in the passband. Meanwhile, the wide beam capability is also realized by the above structure. Furthermore, two H-and E-plane linear arrays are designed for the beam scanning capability with filtering characteristics based on the proposed antenna. To verify the proposed design concept, a prototype is fabricated and measured. The measurement and simulation agree well, demonstrating an excellent filtering characteristic with the operating frequency band from 3.18 to 3.45 GHz(about 8.1%), the high total efficiency of about 88%, and 3-d B-beamwidth of more than 100° and 120° in the above two arrays, respectively. Additionally, the proposed arrays can realize the beam scanning up to the coverage of 112° and 120° with a lower gain reduction and a good filtering characteristic, respectively.

关键词： Antenna measurements Radio frequency Resistance Slot antennas Filtering Communication systems Vehicle-to-infrastructure

Blockchain-Based MCS Detection Framework of Abnormal Spectrum Usage for Satellite Spectrum Sharing Scenario

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China Communications 2024年第2期21卷 32-48页

作者： Ning Yang Heng wang Jingming Hu Bangning Zhang Daoxing Guo Yuan Liu College of Communications Engineering Army Engineering UniversityNanjing 210007China

In this paper, the problem of abnormal spectrum usage between satellite spectrum sharing systems is investigated to support multi-satellite spectrum coexistence. Given the cost of monitoring, the mobility of low-orbit satellites, and the directional nature of their signals, traditional monitoring methods are no longer suitable, especially in the case of multiple power level. Mobile crowdsensing(MCS), as a new technology, can make full use of idle resources to complete a variety of perceptual tasks. However, traditional MCS heavily relies on a centralized server and is vulnerable to single point of failure attacks. Therefore, we replace the original centralized server with a blockchain-based distributed service provider to enable its security. Therefore, in this work, we propose a blockchain-based MCS framework, in which we explain in detail how this framework can achieve abnormal frequency behavior monitoring in an inter-satellite spectrum sharing system. Then, under certain false alarm probability, we propose an abnormal spectrum detection algorithm based on mixed hypothesis test to maximize detection probability in single power level and multiple power level scenarios, respectively. Finally, a Bad out of Good(BooG) detector is proposed to ease the computational pressure on the blockchain nodes. Simulation results show the effectiveness of the proposed framework.

关键词： blockchain hypothesis test mobile crowdsensing satellite communication spectrum sharing

Nano-silica modified lightweight and high-toughness carbon fiber/phenolic ablator with excellent thermal insulation and ablation performance

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Defence Technology（防务技术） 2024年第1期31卷 192-199页

作者： Wenjie Xu Wenda Song Xianfeng Jia Cheng Ma Jitong wang Wenming Qiao Licheng Ling State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering and Materials Changzhou Institute of TechnologyChangzhou 213032China Key Laboratory of Specially Functional Polymeric Materials and Related Technology(Ministry of Education) School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space *** improve the ablative properties,silica sol with good particle size distribution prepared using tetramethoxysilane(TMOS)was blended with natural rubber latex and deposited onto carbon fiber felt,which was then integrated with phenolic aerogel matrix,introducing nano-silica into the framework of *** modified CFPA with a low density of 0.28—0.31 g/cm3exhibits strain-in-fracture as high as 31.2%and thermal conductivity as low as 0.054 W/(m·K).Furthermore,a trace amount of nano-silica could effectively protect CFPA from erosion of oxidizing atmosphere in different high-temperature *** oxyacetylene ablation test of 3000°C for 20 s shows a mass ablation rate of 0.0225 g/s,a linear ablation rate of 0.209 mm/s for the modified CFPA,which are 9.64%and 24.82%lower than the unmodified ***,the long-time butane ablation test of 1200°C for 200 s shows an insignificant recession with mass and linear ablation rate of 0.079 g/s and 0.039 mm/s,16.84%and 13.33%lower than the unmodified ***,the fixed thermocouple in the test also demonstrates a good thermal insulation performance with a low peak back-face temperature of 207.7°C,12.25%lower than the unmodified ***,the nano-silica modified CFPA with excellent overall performance presents promising prospects in high-temperature aerospace applications.

关键词： Nano-silica Carbonfiber Phenolic aerogel Insulation Ablation

Environmentally persistent free radicals in PM_(2.5)from a typical Chinese industrial city during COVID-19 lockdown:The unexpected contamination level variation

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Journal of Environmental Sciences 2024年第1期135卷 424-432页

作者： Lingyun wang Wuduo Zhao Peiru Luo Qingyun He Wenfen Zhang Chuan Dong Yanhao Zhang College of Chemistry Zhengzhou UniversityZhengzhou 450001China Center of Advanced Analysis and Gene Sequencing Key Laboratory of Molecular Sensing and Harmful Substances Detection TechnologyZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Environmental and Biological Analysis Department of ChemistryHong Kong Baptist UniversityHong Kong 999077China Institute of Environmental Science Shanxi UniversityTaiyuan 030006China

The outbreak of COVID-19 has caused concerns *** reduce the rapid transmission of the virus,strict city lockdown measures were conducted in different *** is the country that takes the earliest home-based quarantine for *** normal industrial and social activities were suspended,the spread of virus was efficiently ***,another merit of the city lockdown measure was noticed,which is the improvement of the air *** levels of multiple atmospheric pollutants were ***,in this work,24 and 14 air fine particulate matter(PM_(2.5))samples were continuously collected before and during COVID-19 city lockdown in Linfen(a typical heavy industrial city in China),and intriguingly,the unreduced concentration was found for environmentally persistent free radicals(EPFRs)in PM_(2.5)after normal life *** primary non-stopped coal combustion source and secondary Cu-related atmospheric reaction may have impacts on this *** cigarette-based assessment model also indicated possible exposure risks of PM_(2.5)-bound EPFRs during lockdown of *** study revealed not all the contaminants in the atmosphere had an apparent concentration decrease during city lockdown,suggesting the pollutants with complicated sources and formation mechanisms,like EPFRs in PM_(2.5),still should not be ignored.

关键词： PM_(2.5) EPFRs COVID-19 City lockdown Health risks

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 *** 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 *** multiwatermarking process employs spread transform dither *** the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading ***,multiple watermarks can be simultaneously embedded into the same position of a multimedia ***,the multiple watermarks can be extracted without affecting one another during the extraction *** 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

Chemical Scissors Tailored Nano‑Tellurium with High‑Entropy Morphology for Efficient Foam‑Hydrogel‑Based Solar Photothermal Evaporators

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Nano-Micro Letters 2024年第3期16卷 149-168页

作者： Chenyang Xing Zihao Li Ziao wang Shaohui Zhang Zhongjian Xie Xi Zhu Zhengchun Peng State Key Laboratory of Radio FrequencyHeterogeneous Integration Shenzhen UniversityShenzhen 518060People’s Republic of China Center for Stretchable Electronics and NanoSensors College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhen 518172People’s Republic of China Institute of Pediatrics Shenzhen Children’s HospitalShenzhen 518038GuangdongPeople’s Republic of China International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060People’s Republic of China

The development of tellurium(Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy ***,the nanosized Te(nano-Te)materials reported to date suffer from a series of drawbacks,including limited light absorption and a lack of surface ***,we report the preparation of nano-Te by electrochemical exfoliation using an electrolyzable room-temperature ionic ***,cations,and their corresponding electrolytic products acting as chemical scissors can precisely intercalate and functionalize bulk *** resulting nano-Te has high morphological entropy,rich surface functional groups,and broad light *** also constructed foam hydrogels based on poly(vinyl alcohol)/nano-Te,which achieved an evaporation rate and energy efficiency of 4.11 kg m^(−2)h^(−1)and 128%,respectively,under 1 sun ***,the evaporation rate was maintained in the range 2.5-3.0 kg m^(−2)h^(−1)outdoors under 0.5-1.0 sun,providing highly efficient evaporation under low light conditions.

关键词： Tellurium High entropy Electrochemical modification Solar absorption Evaporation rate

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU Li DING Shi-feng wang Ai-ming CAI Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

Evolution and Application of Sealing Ability of Gypsum Caprocks under Temperature-Pressure Coupling:An Example of the ZS5 Well in the Tazhong Area of the Tarim Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 168-184页

作者： LIU Hua ZHAO Shan YANG Xianzhang ZHU Yongfeng wang Shen ZHANG Ke National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong 266580China School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Laboratory for Marine Mineral Resources National Laboratory for Marine Science and TechnologyQingdaoShandong 266071China PetroChina Tarim Oil Field Company KorlaXinjiang 841001China

Gypsum caprocks'sealing ability is affected by temperature-pressure *** to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure *** stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility *** to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more *** reduces the amount of time it takes for the rock to transition from brittle to *** temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal *** sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are *** provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved.

关键词： temperature-pressure coupling gypsum caprocks brittle-plastic evolution sealing capacity Tarim Basin

Bioactive citrate-based polyurethane tissue adhesive for fast sealing and promoted wound healing

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Regenerative Biomaterials 2024年第1期3卷 69-81页

作者： Yan Li Jiawei Liu Chenxi Lian He Yang Mingjiang Zhang Youfa wang Honglian Dai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Biomedical Materials and Engineering Research Center of Hubei ProvinceWuhan University of TechnologyWuhan 430070China Chaozhou Branch of Chemistry and Chemical Engineering Guangdong Laboratory Chaozhou 521000China Shenzhen Research Institute of Wuhan University of Technology Shenzhen 518000China

As a superior alternative to sutures,tissue adhesives have been developed significantly in recent ***,existing tissue adhesives struggle to form fast and stable adhesion between tissue interfaces,bond weakly in wet environments and lack *** this study,a degradable and bioactive citrate-based polyurethane adhesive is constructed to achieve rapid and strong tissue *** hydrophobic layer was created with polycaprolactone to overcome the bonding failure between tissue and adhesion layer in wet environments,which can effectively improve the wet bonding *** citrate-based polyurethane adhesive provides rapid,non-invasive,liquid-tight and seamless closure of skin incisions,overcoming the limitations of sutures and commercial tissue *** addition,it exhibits biocompatibility,biodegradability and hemostatic *** degradation product citrate could promote the process of angiogenesis and accelerate wound *** study provides a novel approach to the development of a fast-adhering wet tissue adhesive and provides a valuable contribution to the development of polyurethane-based tissue adhesives.

关键词： tissue adhesive polyurethane citrate wet adhesion