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Chinese Journal of Polymer Science 2024年第10期42卷 1610-1618,I0016页

作者： Xin-Yu chen Yu-bing Fu Xue-Ling Yan Lan Liu School of Materials Science and Engineering Key Lab of Guangdong Province for High Property and Functional Polymer MaterialsSouth China University of TechnologyGuangzhou510641China

Elastomers with high strength and toughness,excellent self-healing properties,and biocompatibility have broad application prospects in wearable electronics and other fields,but preparing it remains a *** this work,we propose a highly adaptable strategy by introducing the small molecule crosslinking agent of triethanolamine(TEA)to the poly(thioctic acid)(PTA)chains and preparing the PAx Ey elastomers using a simple synthesis *** strategy stabilizes the PTA chains by constructing multiple non-covalent cross-linked dynamic networks,endowing materials with excellent strength and toughness(tensile strength of 288 kPa,toughness of 278.2 kJ/m3),admirable self-healing properties(self-healing efficiency of 121.6%within 7 h at 70℃),and good *** PAx Ey elastomers can also be combined with MWNTs to become flexible strain sensors,which can be used to monitor human joint movements with high sensitivity,repeatable responses,and stability.

关键词： Thioctic acid Ion clusters Multiple dynamic networks Self-healing strengthening Flexible strain sensor

Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

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Petroleum Science 2024年第2期21卷 777-790页

作者： bing-Kun Meng Dao-Fu Song Yuan chen Sheng-Bao Shi School of Petroleum Engineering and Environmental Engineering Yan'an UniversityYan'an716000ShaanxiChina State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing102249China

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude *** on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient *** samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter *** should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

关键词： 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment

Analysis of metabolic characteristics of metabolic syndrome in elderly patients with gastric cancer by non-targeted metabolomics

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2419-2428页

作者： Huan Zhang Wen-bing Shen Lin chen Medical School of Chinese PLA Chinese PLA General HospitalBeijing 100853China Department of Gastrointestinal Surgery Shanghai Sixth People’s HospitalShanghai 250063China Department of General Surgery The First Medical Center of Chinese PLA General HospitalBeijing 100853China

BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much ***,the specific metabolic characteristics of MetS in elderly patients with GC remain *** To investigate the differentially abundant metabolites and metabolic pathways between preoperative frailty and MetS in elderly patients with GC based on nontargeted metabolomics *** In this study,125 patients with nonfrail nonmeal GC were selected as the control group,and 50 patients with GC in the frail group were selected as the frail ***-five patients with GC combined with MetS alone were included in the MetS group,and 50 patients with GC combined with MetS were included in the MetS *** metabolomics techniques were used to measure plasma metabolite levels by ultrahigh-performance liquid chromatography-mass *** statistical analysis was performed by principal component analysis,orthogonal partial least squares,pattern recognition analysis,cluster analysis,and metabolic pathway *** A total of 125 different metabolites,including amino acids,glycerophospholipids,sphingolipids,fatty acids,sugars,nucleosides and nucleotides,and acidic compounds,were identified via nontargeted metabolomics *** with those in the control group,there were 41,32,and 52 different metabolites in the MetS group,the debilitated group,and the combined group,*** metabolites were significantly increased in the MetS *** the weak group,amino acids and most glycerol phospholipid metabolites decreased significantly,and fatty acids and sphingosine increased *** combined group was characterized by significantly increased levels of nucleotide metabolites and acidic *** alanine,aspartic acid,and glutamate metabolic pathways were obviously enriched in the asthenic group,and the glycerol and phospholipid metabolic pathways were obv

关键词： Nervous breakdown Metabolic syndrome Elderly individuals Gastric cancer Nontargeted metabolomics

Quantitative method for calculating spatial release region for laser-guided bomb

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Journal of Systems Engineering and Electronics 2024年第4期35卷 1053-1062页

作者： YANG Ping XIAO bing chen Xin HAO Yuntao Air Force Early Warning Academy Wuhan 430019China Unit 93175 of the PLA Changchun 136000China

The laser-guided bomb(LGB)is an air-to-ground pre-cision-guided weapon that offers high hit rates,great power,and ease of *** are guided by semi-active laser ground-seek-ing technology,which means that atmospheric conditions can affect their *** spatial release region(SRR)of LGBs is difficult to calculate precisely,especially when there is a poor field of *** can result in a lower real hit *** increase the hit probability of LGBs in tough atmospheric situa-tions,a novel method for calculating the SRR has been *** method is based on the transmittance model of the 1.06μm laser in atmospheric species and the laser diffuse reflection model of the target surface to determine the capture target time of the laser ***,it calculates the boundary ballistic space starting position by ballistic model and gets the spatial scope of the spatial release *** method can determine the release region of LGBs based on flight test data such as instantaneous velocity,altitude,off-axis angle,and atmospheric *** more effectively employing aircraft release conditions,atmospheric visibility and other factors,the SRR calculation method can improve LGB hit probabi-lity by 9.2%.

关键词： laser-guided bombs(LGBs) hit probability atmo-spheric transmittance spatial release region(SRR)boundary ballistic

Cavity-enhanced metrology in an atomic spin-1 Bose−Einstein condensate

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Frontiers of physics 2024年第3期19卷 185-196页

作者： Renfei Zheng Jieli Qin bing chen Xingdong Zhao Lu Zhou School of Physics Hefei University of TechnologyHefei 230009China State Key Laboratory of Precision Spectroscopy Department of PhysicsSchool of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China School of Physics and Materials Science Guangzhou University230 Wai Huan Xi RoadGuangzhou Higher Education Mega CenterGuangzhou 510006China Department of Physics Henan Normal UniversityXinxiang 453007China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Atom interferometer has been proven to be a powerful tool for precision metrology. Here we propose a cavity-aided nonlinear atom interferometer, based on the quasi-periodic spin mixing dynamics of an atomic spin-1 Bose−Einstein condensate trapped in an optical cavity. We unravel that the phase sensitivity can be greatly enhanced with the cavity-mediated nonlinear interaction. The influence of encoding phase, splitting time and recombining time on phase sensitivity are carefully studied. In addition, we demonstrate a dynamical phase transition in the system. Around the criticality, a small cavity light field variation can arouse a strong response of the atomic condensate, which can serve as a new resource for enhanced sensing. This work provides a robust protocol for cavity-enhanced metrology.

关键词： nonlinear atom interferometer spin-1 Bose−Einstein condensate spin-mixing dynamics quantum Fisher information parameter estimation

Beating the Fault-Tolerance Bound and Security Loopholes for Byzantine Agreement with a Quantum Solution

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Research 2024年第3期2023卷 445-455页

作者： chen-Xun Weng Rui-Qi Gao Yu Bao bing-Hong Li Wen-Bo Liu Yuan-Mei Xie Yu-Shuo Lu Hua-Lei Yin Zeng-bing chen National Laboratory of Solid State Microstructures and School of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education)Renmin University of ChinaBeijing 100872China.

Byzantine agreement,the underlying core of blockchain,aims to make every node in a decentralized network reach *** Byzantine agreements unavoidably face two major *** is 1/3 fault-tolerance bound,which means that the system to tolerate f malicious players requires at least 3f+1 *** other is the security loopholes from its classical cryptography ***,we propose a Byzantine agreement framework with unconditional security to break this bound with nearly 1/2 fault tolerance due to multiparty correlation provided by quantum digital *** is intriguing that quantum entanglement is not necessary to break the 1/3 fault-tolerance bound,and we show that weaker correlation,such as asymmetric relationship of quantum digital signature,can also *** work strictly obeys two Byzantine conditions and can be extended to any number of players without requirements for multiparticle *** experimentally demonstrate three-party and five-party consensus for a digital *** work indicates the quantum advantage in terms of consensus problems and suggests an important avenue for quantum blockchain and quantum consensus networks.

关键词： methods. quantum signature

Effect of Long Protocol on the Outcome of In Vitro Fertilization-embryo Transfer in Patients with Endometriosis Compared with Prolonged Protocol

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Journal of Reproduction and Contraception 2014年第2期25卷 81-88页

作者： Jian-ping ZHANG Xue-qing WU Xing-yu BI bing-bing chen Si-ping ZHANG Hui-ping LIU Human Assisted Reproduction Center Shanxi Women & Children's Hospital

Objective To investigate the effect of different down-regulation protocol on the in vitro fertilization-embryo transfer （IVF-ET） outcomes in infertile patients with endometriosis （EMs）.Methods A retrospective case control study was performed. Totally 294 infertile patients with EMs were enrolled. And 109 patients （116 cycles） received prolongedprotocol as the control, 185 patients （193 cycles） received long protocol as case group, all followed by standard controlled ovarian hyperstimulation （COH）. Response to gonadotropins, the fertilization rate, the cleavage rate, the implantation rate, the clinical pregnancy rate and the miscarriage rate were measured and analyzed between the two groups. Results A trend toward better ovarian response was observed in long protocol group. Higher fertilization rate, lower total dose of rFSH, shorter duration of stimulation and more endometrial thickness on the day of hCG injection were observed in long protocol group compared with those of prolonged protocol group, and the difference was significant （P〈0.05）. In addition, the clinical pregnancy rate, the cleavage rate and the implantation rate also had an increase trend in long protocol group compared with those of prolonged protocol group, but without significant differences. Conclusion Long protocol regimen before IVF-ET in patients with EMs resulted in a trend toward better ovarian response and higher clinical pregnancy rates than prolonged protocol regimen did.

关键词： endometriosis (EMs) down-regulation protocol controlled ovarianhyperstimulation (COH) IVF-ET pregnancy rate

Inclusions modification by rare earth in steel and the resulting properties: A review

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Journal of Rare Earths 2024年第3期42卷 431-445,I0001页

作者： Xiaoqiang Wang Zhiwei Wu bing Li Wenxiong chen Jun Zhang Jian Mao College of Materials Science and Engineering Sichuan UniversityChengdu610065China chengdu Advanced Metal Materials Industry Technology Research Institute Co. Ltd.Chengdu610303China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114009China

Rare earth(RE) elements are excellent modifiers for non-metallic inclusions that inevitably appear in steel and affect steel properties. This paper reviews the research status of inclusions modification by RE elements and the changes it cause on steel properties. First, the inclusion changes caused by RE modification are described. Generally, after adding pure RE, the main evolution of inclusions occurs as M →M + RE-Al-O → RE-Al-O + RE_(2)O_(2)S → RE_(2)O_(2)S + RE—S/RE_(2)O_(2)S + RE-O with an increase in the RE content(M represents the inclusions before RE addition). The type of final inclusion obtained after RE modification is related to the relative contents of S and O in the steel. Moreover, fine, regular, and uniformly distributed inclusions can be obtained with appropriate RE addition. However, the effectiveness of inclusions modification by adding both RE and non-RE elements is closely related to the order of their addition. Second, the applications and advantages of thermodynamic calculations in the study of RE-modified inclusions are introduced. Third, the changes in the corrosion resistance, impact properties,and other properties of steel caused by the modification of inclusions by RE are reviewed. Finally, the perspectives and trends of inclusions modified by RE elements in the steel industry are presented.

关键词： Rare earths Inclusions Modification Thermodynamic calculation Properties change

Identification and Characteristics Analysis of Micro-Seismic Signals in the Haima Seep Area

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Journal of Earth Science 2024年第1期35卷 288-291页

作者： Xiangchun Wang bing Nie Zhiyu Wu Weiwei Wang Hua chen China University of Geosciences Beijing 100083China CNOOC China Limited Shenzhen BranchShenzhen 518000China Guangzhou Marine Geological Survey Guangzhou 511458China CNOOC China Limited Shanghai BranchShanghai 200335China

*** recent years,with the steady development of offshore energy exploration technology,submarine gas seepage sites,and their products are gradually being identified and *** submarine cold seep is a seepage phenomenon in which hydrocarbon gases stored deep in the seafloor are transported to seawater by gushing or seepage under the action of tectonic compression(Roy et al.,2019;Tinivella and Giustiniani,2016).

关键词： submarine Seismic offshore

Real-time arrival picking of rock microfracture signals based on convolutional-recurrent neural network and its engineering application

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 761-777页

作者： bing-Rui chen Xu Wang Xinhao Zhu Qing Wang Houlin Xie State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Accurately picking P-and S-wave arrivals of microseismic(MS)signals in real-time directly influences the early warning of rock mass failure.A common contradiction between accuracy and computation exists in the current arrival picking ***,a real-time arrival picking method of MS signals is constructed based on a convolutional-recurrent neural network(CRNN).This method fully utilizes the advantages of convolutional layers and gated recurrent units(GRU)in extracting short-and long-term features,in order to create a precise and lightweight arrival picking ***,the synthetic signals with field noises are used to evaluate the hyperparameters of the CRNN model and obtain an optimal CRNN *** actual operation on various devices indicates that compared with the U-Net method,the CRNN method achieves faster arrival picking with less performance *** application of large underground caverns in the Yebatan hydropower station(YBT)project shows that compared with the short-term average/long-term average(STA/LTA),Akaike information criterion(AIC)and U-Net methods,the CRNN method has the highest accuracy within four sampling points,which is 87.44%for P-wave and 91.29%for S-wave,*** sum of mean absolute errors(MAESUM)of the CRNN method is 4.22 sampling points,which is lower than that of the other *** the four methods,the MS sources location calculated based on the CRNN method shows the best consistency with the actual failure,which occurs at the junction of the shaft and the second ***,the proposed method can pick up P-and S-arrival accurately and rapidly,providing a reference for rock failure analysis and evaluation in engineering applications.

关键词： Rock mass failure Microseismic event P-wave arrival S-wave arrival Deep learning