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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

Quasi-two dimensional Ruddlesden−Popper halide perovskites for laser applications

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Frontiers of physics 2024年第2期19卷 53-71页

作者： Kun Chen Qianpeng Zhang Yin liang Jiepeng Song chun li Shi Chen Fang li Qing Zhang School of Mechanical and Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China School of Materials Science and Engineering Peking UniversityBeijing 100871China Institute of Applied Physics and Materials Engineering Macao UniversityMacao 999078China

Quasi-two-dimensional(2D)Ruddlesden‒Popper(RP)halide perovskites,as a kind of emerged two-dimensional layered materials,have recently achieved great attentions in lasing materials field owing to their large exciton binding energy,high emission yield,large optical gain,and wide-range tuning of optical *** review will introduce research progresses of RP halide perovskites for lasing applications in aspects of materials,photophysics,and devices with emphasis on emission and lasing properties tailored by the molecular composition and *** materials,structures and fabrications are introduced in the first ***,the optical transitions and amplified spontaneous emission properties are discussed from the aspects of electronic structure,exciton,gain dynamics,and interface ***,the research progresses on lasing devices are summarized and several types of lasers including VCSEL,DFB lasers,microlasers,random lasers,plasmonic lasers,and polariton lasers are *** last,the challenges and perspectives would be provided.

关键词： two-dimensional materials metal halide perovskite Ruddlesden−Popper halide perovskites lasing emission

Synthesis,Characterization of Polyethylene Ionomers and Their Antibacterial Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1077-1084页

作者： Jia-Jia Wu Fei Wang Peng-Qi Wan li Pan chun-Sheng Xiao Zhe Ma Yue-Sheng li Tianjin Key Lab Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Key Lab Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Owing to its high production volume and wide range of application s,polyethylene has gained a great deal of attention,but its low surface energy and non-polar nature have limited its application in some important *** this study,ethylene/11-iodo-1-undecene copolymers were prepared and used as the intermediates to afford a series of imidazolium-based ionomers bearing methanesulfonate(CH_(3)SO_(3)^(-)),trifluoromethanesulfonate(CF_(3)SO_(3)^(-)),or bis(trifluoromethane)sulfonimide(Tf_(2)N^(-))*** tensile test results showed that the stress-at-break(7.8-25.6 MPa)and the elongation-at-break(445%-847%)of the ionomers could be adjusted by changing the counterion species and the ionic group *** importantly,the ionomers exhibited marvelous antibacterial activities against Staphylococcus aureus(***)and Escherichia coli(***).The ionomers bearing Tf_(2)N^(-)exhibited antibacterial activities>99%against both *** and *** when ionic content reached 9.1%.The imidazolium-based ionomers prepared in this work demonstrated excellent comprehensive properties,especially highefficient and broad-spectrum antibacterial ability,exhibiting the potential fo r the application as the antibacterial materials in packaging,medical,and other fields.

关键词： Polyethylene Ionomer Polymerization catalysis Imidazolium Antibacterial material

Molecular mechanism for the unusual enhancement of the second-step chemiluminescence production from the carcinogenic tetrabromohydroquinone and H2O_(2)

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Journal of Environmental Sciences 2024年第7期141卷 330-342页

作者： Zi-Han Wang chun-Hua Huang Zhi-Sheng liu li Mao Ben-Zhan Zhu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environment and Resources University of Chinese Academy of SciencesBeijing 100049China

We have found recently that two-step intrinsic hydroxyl radical(·OH)-dependent chemiluminescence(CL)could be produced by carcinogenic tetrahaloquinone and H_(2)O_(2).However,the first-step CL was too fast to clearly detect the stepwise generation of·OH and CL,and to distinguish the exact dividing point between the first-step and second-step *** we found that,extremely clear two-step intrinsic CL could be produced by the relative slow reaction of tetrabromohydroquinone(TBHQ)with H_(2)O_(2),which was directly dependent on the two-step·OH ***,the second-step,but not the first-step CL production of TBHQ/H_(2)O_(2)(CRET donor)was markedly enhanced by fluorescein(a typical xanthene dye,CRET acceptor)through a unique chemiluminescence resonance energy transfer(CRET)*** novel CRET system of TBHQ/H_(2)O_(2)/fluorescein was successfully applied for the sensitive detection of TBHQ with the detection limit as low as 2.5μmol/*** findings will help to develop more sensitive and highly efficient CL or CRET systems and specific CL sensor to detect the carcinogenic haloquinones,which may have broad environmental applications.

关键词： Two-step chemiluminescence Bromohydroquinone Hydrogen peroxide Hydroxyl radical CRET

Improvement of the nutritional support management system for patients in intensive care units

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World Journal of Psychiatry 2024年第1期14卷 44-52页

作者： Yuan-Yuan Zhang chun-Yi Wang Dong-Xian Guo hai-Nu Gao Xian-Shan Jin Yan-li Wu Lu-Han Chen Zhi-Xian Feng Department of Critical Care Medicine Shulan(Hangzhou)HospitalZhejiang Shuren University Shulan International Medical CollegeHangzhou 310022Zhejiang ProvinceChina Department of Information Shulan(Hangzhou)HospitalZhejiang Shuren University Shulan International Medical CollegeHangzhou 310022Zhejiang ProvinceChina Department of Pharmacy Shulan(Hangzhou)HospitalZhejiang Shuren University Shulan International Medical CollegeHangzhou 310022Zhejiang ProvinceChina Department of Nutrition Shulan(Hangzhou)HospitalZhejiang Shuren University Shulan International Medical CollegeHangzhou 310022Zhejiang ProvinceChina Administrative Office Shulan(Hangzhou)HospitalZhejiang Shuren University Shulan International Medical CollegeHangzhou 310022Zhejiang ProvinceChina

BACKGROUND Nutritional support for patients hospitalized in the intensive care unit(ICU)is an important part of clinical treatment and care,but there are significant implementation *** To introduce a modified nutritional support management system for ICU patients based on closed-loop information management and psychological *** The division of functions,personnel training,system construction,development of an intelligent decision-making software system,quality control,and improvement of the whole process were carried out to systematically manage nutritional support for ICU *** Following the implementation of the whole process management system,the scores of ICU medical staff’s knowledge,attitudes/beliefs,and practices regarding nutritional support were comprehensively *** proportion of hospital bed-days of total enteral nutrition(EN)in ICU patients increased from 5.58%to 11.46%,and the proportion of EN plus parenteral nutrition increased from 42.71%to 47.07%.The rate of EN initiation within 48 h of ICU admission increased from 37.50%to 48.28%,and the EN compliance rate within 72 h elevated from 20.59%to 31.72%.After the implementation of the project,the Self-rating Anxiety Scale score decreased from 61.07±9.91 points to 52.03±9.02 points,the Self-rating Depression Scale score reduced from 62.47±10.50 points to 56.34±9.83 points,and the ICU stay decreased from 5.76±2.77 d to 5.10±2.12 *** The nutritional support management system based on closed-loop information management and psychological counseling achieved remarkable results in clinical applications in ICU patients.

关键词： Closed-loop information Psychological counseling Intensive care unit patients Nutritional support Management system

(+)/(-)-Gerbeloid A,a pair of unprecedented coumarin-based polycyclic meroterpenoid enantiomers from Gerbera piloselloides:Structural elucidation,semi-synthesis,and lipid-lowering activity

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2657-2668页

作者： Chenxu Zhao Jingrong li Yue Hu lingyu li Meng Yu Yunfeng Huang Tao Zhang hai Shang Zhongmei Zou State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China Institute of Chinese Medicine Resources Guangxi Institute of Chinese Medicine&Pharmaceutical ScienceNanning 530000China

A pair of coumarin-based polycyclic meroterpenoid enantiomers(+)/(-)-gerbeloid A[(+)-1a and(-)-1b]were isolated from the medicinal plant Gerbera piloselloides,which have a unique caged oxatricyclo[4.***.2.0^(3,8)]decene *** planar and three-dimensional structures were exhaustively characterized by comprehensive spectroscopic data and X-ray diffraction *** by the hypothetical biosynthetic pathway,the biomimetic synthesis of racemic 1 was achieved using 4-hydroxy-5-methylcoumarin and citral as the starting material via oxa-6πelectrocyclization and intramolecular[2+2]***,the results of the biological activity assay demonstrated that both(+)-1a and(-)-1b exhibited potent lipid-lowering effects in 3T3-L1 adipocytes and the high-fat diet zebrafish ***,the lipid-lowering activity of(+)-1a is better than that of(-)-1b at the same concentration,and molecular mechanism study has shown that(+)-1a and(-)-1b impairs adipocyte differentiation and stimulate lipolysis by regulating C/EBPα/PPARγsignaling and Perilipin signaling in vitro and in *** findings provide a promising drug model molecule for the treatment of obesity.

关键词： Gerbera piloselloides Natural products Coumarin meroterpenoid Structural elucidation Biomimetic synthesis lipid-lowering activity 3T3-L1 adipocytes High-fat diet zebrafish model

Polymer-on-HOF:a new strategy for fabricating“armour-plated”HOFs to sequester radioactive anions

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Science China Chemistry 2024年第9期67卷 2958-2967页

作者： hai-Ruo li Shitao Wu Xuezhuo Jing Zhengyi Di Kun liu Lu Wang Cheng-Peng li Zhong liu Miao Du College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China Shanghai Key Laboratory of High-Resolution Electron Microscopy School of Physical Science and TechnologyShanghaiTech UniversityShanghai 201210China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Provincial Key Laboratory of Resources and Chemistry of Salt LakesQinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China College of Material and Chemical Engineering Institute of New Energy Science and TechnologySchool of Future Hydrogen Energy TechnologyZhengzhou University of Light IndustryZhengzhou 450001China

The development of hydrogen-bonded organic frameworks(HOFs)faces significant constraints,primarily attributed to their fragile architectures and limited functionalization *** overcome these limitations,this work presents a new polymeron-HOF strategy by covalently tethering armor-like polymers onto the surface of *** application of this approach not only bolsters the stability of HOFs,but also facilitates the customization of their functional expansion in radionuclide *** optimized HOF-polymer materials display extraordinary ability in radionuclide sequestration,achieving uptake of I^(-)(0.699 g g^(-1)),IO_(3)^(-)(0.285 g g^(-1))and ReO_(4)^(-)(1.616 g g^(-1),setting a world record),fast adsorption kinetics(~100% removal within 45 s),and exceptional regeneration capability(>30 cycles)under continuous flow *** outstanding performances benefit from the internal porous channels and surface imidazolium polymer coatings of HOFs,as proved by density functional theory calculation and molecular dynamics *** work paves the way for the rational design of HOF-based hybrid materials tailored to versatile applications.

关键词： hydrogen-bonded organic frameworks(HOFs) post-synthetic modification radionuclide sequestration

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Research on casing deformation prevention technology based on cementing slurry system optimization

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： Yan Yan Meng Cai Wen-hai Ma Xiao-Chuan Zhang li-Hong Han Yong-Hong liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test

Rationally designing electrolyte additives for highly improving cyclability of liNi_(0.5)Mn_(1.5)O_(4)/Graphite cells

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Journal of Energy Chemistry 2024年第4期91卷 266-275页

作者： Zhiyong Xia Kuan Zhou Xiaoyan lin Zhangyating Xie Qiurong Chen Xiaoqing li Jie Cai Suli li hai Wang Mengqing Xu Weishan li School of Chemistry South China Normal UniversityGuangzhou 510006GuangdongChina China Zhuhai CosMX Battery Co. Ltd.Zhuhai 519180GuangdongChina National and Local Joint Engineering Research Center of MPTES in High Energy and Safety liBs Engineering Research Center of MTEES(Ministry of Education)and Key Lab.of ETESPG(GHEI)South China Normal UniversityGuangzhou 510006GuangzhouChina

High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high voltage lithium-ion battery,liNi_(0.5)Mn_(1.5)O_(4)/Graphite(LNMO/Graphite)cell,which emphasizes a rational design of an electrolyte additive that can effectively construct protective interphases on anode and cathode and highly eliminate the effect of hydrogen fluoride(HF).5-Trifluoromethylpyridine-trime thyl lithium borate(LTFMP-TMB),is synthesized,featuring with *** anion TFMPTMB-tends to be enriched on cathode and can be preferentially oxidized yielding TMB and radical TFMP-.Both TMB and radical TFMP can combine HF and thus eliminate the detrimental effect of HF on cathode,while the TMB dragged on cathode thus takes a preferential oxidation and constructs a protective cathode *** the other hand,LTFMP-TMB is preferentially reduced on anode and constructs a protective anode ***,a small amount of LTFMP-TMB(0.2%)in 1.0 M liPF6in EC/DEC/EMC(3/2/5,wt%)results in a highly improved cyclability of LNMO/Graphite cell,with the capacity retention enhanced from 52%to 80%after 150 cycles at 0.5 C between 3.5 and 4.8 *** as-developed strategy provides a model of designing electrolyte additives for improving cyclability of high voltage batteries.

关键词： Electrolyte additive Design and synthesis Cyclability High voltage batteries Cathode and anode interphases