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Resolving aging dynamics of a 3D colloidal glass

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 110-118页

作者： XiaoJuan Wang Jun Duan Gan Ding YunZhuo lu Xing lu LanHong dai MinQiang Jiang State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Physical aging is an inherent property of glassy matter, but understanding its microscopic mechanism remains a challenge particularly at the particle level. In this work, we use a confocal microscope to in-situ trace the particle trajectories in a 3D colloidal glass for 73000 s, aiming at resolving the aging dynamics. By calculating the mean square displacement of particle motions, we find that the glass aging with time can be divided into three stages: β relaxation, α relaxation and free diffusion. The system's mean square displacement at each aging state is quantitatively resolved into three contributions of particle dynamics modes: vibration within the nearest-neighbor cages, hopping between cages and cooperative rearrangement. We further calculate the particle's free volume and find that the β-to-α transition is accompanied by the temporary increase of the system-averaged free volume due to pronounced hops of particles. Nevertheless, the temporal autocorrelation of the free volume spatial distribution still obeys a monotonically stretched exponential decay with an exponent of 0.76, which is related to the sub-diffusion dynamics of cooperative rearrangements and hops mixed in α relaxation. According to the resolved vibrational displacements,we calculate the vibrational density of states of this 3D glass, and the characteristic boson peak is reproduced at low frequencies.Our findings shed insight into the particle-level aging dynamics of a real glass under purely thermal activation.

关键词： colloidal glass physical aging particle dynamics free volume boson peak

Asymmetric copolyimide membranes fabricated by nonsolvent-induced phase separation for He/CH_(4) and He/N_(2) separation

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 97-106页

作者： Ying Li lu Wang Junyan Xie Yong dai Xuehong Gu Xuerui Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China Quzhou Membrane Material Innovation Institute Quzhou 324000China

Membrane gas separation is considered an energy-saving technique to extract He from natural gas due to no phase change and room temperature operation.However,the membrane performance was strongly limited by the trade-off between permeance and selectivity.Herein,novel 4,4′-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)-2,2′-bis(3-amino-4-hydroxyphenyl)hexafluoropropane(APAF)-5-amino-2-(4-aminobenzene)benzimidazole(BIA)asymmetric membranes with a thickness of 300 nm were successfully prepared by the non-solvent induced phase separation method.The membrane performance was modulated by regulating dope solution compositions(e.g.,tetrahydrofuran and polymer concentration).The ideal He/CH_(4) selectivity was 124 and the optimized He permeance reached 87 GPU,beyond the current upper bound.He/CH_(4) selectivity was 75 and He permeance was 73 GPU for the binary mixture feed containing 0.2 mol%He.The membrane showed good resistance to CO_(2) and C_(2)H_(6),which are the typical impurities in natural gas.The 6FDA-APAF-BIA membranes have good stability(>160 h),which can provide great potential in He extraction from natural gas.

关键词： He separation membrane natural gas copolyimide

RL and AHP-Based Multi-Timescale Multi-Clock Source Time Synchronization for Distribution Power Internet of Things

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Computers, Materials & Continua 2024年第3期78卷 4453-4469页

作者： Jiangang lu Ruifeng Zhao Zhiwen Yu Yue dai Kaiwen Zeng Electric Power Dispatching and Control Center Guangdong Power Grid Co.Ltd.Guangzhou510600China

Time synchronization(TS)is crucial for ensuring the secure and reliable functioning of the distribution power Internet of Things(IoT).Multi-clock source time synchronization(MTS)has significant advantages of high reliability and accuracy but still faces challenges such as optimization of the multi-clock source selection and the clock source weight calculation at different timescales,and the coupling of synchronization latency jitter and pulse phase difference.In this paper,the multi-timescale MTS model is conducted,and the reinforcement learning(RL)and analytic hierarchy process(AHP)-based multi-timescale MTS algorithm is designed to improve the weighted summation of synchronization latency jitter standard deviation and average pulse phase difference.Specifically,the multi-clock source selection is optimized based on Softmax in the large timescale,and the clock source weight calculation is optimized based on lower confidence bound-assisted AHP in the small timescale.Simulation shows that the proposed algorithm can effectively reduce time synchronization delay standard deviation and average pulse phase difference.

关键词： Multi-clock source time synchronization(TS) power Internet of Things reinforcement learning analytic hierarchy process

Bioinspired Hemostatic Strategy via Pulse Ejections for Severe Bleeding Wounds

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Research 2024年第1期2023卷 281-299页

作者： Bitao lu Enling Hu Weiwei Ding Wenyi Wang Ruiqi Xie Kun Yu Fei lu Guangqian Lan Fangyin dai State Key Laboratory of Silkworm Genome Biology College of SericultureTextile and Biomass SciencesSouthwest UniversityChongqing 400715China Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile Chongqing 400715China Division of Trauma and Surgical Intensive Care Unit Research Institute of General SurgeryJinling HospitalMedical School of Nanjing UniversityNanjing210002 Jiangsu ProvinceChina Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic UniversityHong KongChina

Efficient hemostasis during emergency trauma with massive bleeding remains a critical challenge in prehospital settings.Thus,multiple hemostatic strategies are critical for treating large bleeding wounds.In this study,inspired by bombardier beetles to eject toxic spray for defense,a shape-memory aerogel with an aligned microchannel structure was proposed,employing thrombin-carrying microparticles loaded as a built-in engine to generate pulse ejections for enhanced drug permeation.Bioinspired aerogels,after contact with blood,can rapidly expand inside the wound,offering robust physical barrier blocking,sealing the bleeding wound,and generating a spontaneous local chemical reaction causing an explosivelike generation of CO_(2) microbubbles,which provide propulsion thrust to accelerate burst ejection from arrays of microchannels for deeper and faster drug diffusion.The ejection behavior,drug release kinetics,and permeation capacity were evaluated using a theoretical model and experimentally demonstrated.This novel aerogel showed remarkable hemostatic performance in severely bleeding wounds in a swine model and demonstrated good degradability and biocompatibility,displaying great potential for clinical application in humans.

关键词： wound sealing offering

Defects in phospholipase C zeta cause polyspermy and low fertilization after conventional IVF:not just ICSI failure

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Asian Journal of Andrology 2024年第2期26卷 175-182页

作者： Jian-Fang Che Hui-Xia Wu Si-Cong Zeng Yue-Ren Wu Jing dai De-Hua Cheng Fei Gong Guang-Xiu lu Ge Lin Can dai School of Medicine Hunan Normal UniversityChangsha 410013China Reproductive and Genetic Hospital of CITIC-Xiangya Changsha 410008China Clinical Research Center for Reproduction and Genetics in Hunan Province Changsha 410078China National Engineering and Research Center of Human Stem Cell Changsha 410205China

Phospholipase C zeta(PLC)is a key sperm-borne oocyte-activating factor that triggers Ca^(2+)oscillations and the subsequent block to polyspermy following gamete fusion.Mutations in PLCZ1,the gene encoding PLCζ,cause male infertility and intracytoplasmic sperm injection(ICSI)fertilization failure;and PLCζ expression and localization patterns are significantly correlated with ICSI fertilization rate(FR).However,in conventional in vitro fertilization(cIVF),whether and how sperm PLCζ affects fertilization remain unclear.Herein,we identified one previously reported and two novel PLCZ1 mutations associated with polyspermy in vitro that are characterized by excessive sperm-zona binding and a delay in pronuclei(PN)formation.Immunofluorescence staining and oocyte activation testing revealed that virtually all spermatozoa from patients lacked functional PLCζ and were thus unable to evoke Ca^(2+) oscillations.ICSI with an artificial oocyte activation treatment successfully rescued the polyspermic phenotype and resulted in a live birth.Furthermore,we analyzed PLCζ in an additional 58 males after cIVF treatment in the Reproductive and Genetic Hospital of CiTiC-Xiangya(Changsha,China)between February 2019 and January 2022.We found that the proportion of spermatozoa that expressed PLCζ was positively correlated with both 2PN rate and total FR.The optimal cutoff value below which males were likely to experience low FR(total FR≤30%)after clVF was 56.7%for the proportion of spermatozoa expressing PLC5.Our study expands the mutation and the phenotypic spectrum of PLCZ1 and further suggests that PLCζ constitutes a promising biomarker for identifying low FRs cases in cIVF due to sperm-related oocyte activation deficiency and that sperm PLCζ analysis may benefit the widermale population and not onlymen with IcsI failure.

关键词： conventional IVF gene variants PLCζ polyspermy

Semantic information processing for interoperability in the Industrial Internet of Things

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Fundamental Research 2024年第1期4卷 8-12页

作者： Shengshi Yao Yanpeng lu Kai Niu Jincheng dai Chao Dong Ping Zhang Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China The State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

With the advent of the Internet of Everything(IoE),the concept of fully interconnected systems has become a reality,and the need for seamless communication and interoperability among different industrial systems has become more pressing than ever before.To address the challenges posed by massive data traffic,we demonstrate the potentials of semantic information processing in industrial manufacturing processes and then propose a brief framework of semantic processing and communication system for industrial network.In particular,the scheme is featured with task-orientation and collaborative processing.To illustrate its applicability,we provide examples of time series and images,as typical industrial data sources,for practical tasks,such as lifecycle estimation and surface defect detection.Simulation results show that semantic information processing achieves a more efficient way of information processing and exchanging,compared to conventional methods,which is crucial for handling the demands of future interconnected industrial networks.

关键词： Semantic communication Intelligent manufacturing Signal processing Industrial Internet Task-oriented communication

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-Lin Fan Feng Zhang Qian Chen Hao-Chen Song lu-Yu Zhong Yue-Xiang dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and gas.However,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal density.In this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection system.The spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response functions.Combined with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal density.This approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal density.This accuracy level is ten times higher compared to density accuracy calculated using calibration equations.Overall,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

Efficient electroreduction of nitrate via enriched active phases on copper-cobalt oxides

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Chinese Chemical Letters 2024年第4期35卷 204-209页

作者： Ling Fang Sha Wang Shun lu Fengjun Yin Yujie dai Lin Chang Hong Liu Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China University of Chinese Academy of Sciences Beijing 100049China

Electrochemical conversion of nitrate(NO_(3)~-) to ammonia(NH_(3)) can target two birds with one stone well, in NO_(3)^(-)-containing sewage remediation and sustainable NH_(3) production. However, single metalbased catalysts are difficult to drive high-efficient NO_(3)~- removal due to the multi-electron transfer steps.Herein, we present a tandem catalyst with simple structure, Cu-Co binary metal oxides(Cu-Co-O), by engineering intermediate phases as catalytic active species for NO_(3)~- conversion. Electrochemical evaluation,X-ray photoelectron spectroscopy, and in situ Raman spectra together suggest that the newly-generated Cu-based phases was prone to NO_(3)~- to NO_(2)~- conversion, then NO_(2)~- was reduced to NH_(3) on Co-based species. At an applied potential of -1.1 V vs. saturated calomel electrode, the Cu-Co-O catalyst achieved NO_(3)~- -N removal of 90% and NH_(3) faradaic efficiency of 81% for 120 min in 100 m L of 50 mg/L NO_(3)~- -N,consuming only 0.69 k Wh/mol in a two-electrode system. This study provides a facile and efficient engineering strategy for developing high-performance catalysts for electrocatalytic nitrate conversion.

关键词： NO_(3)^(-)-containing sewage remediation Electrocatalytic reduction Copper-cobalt oxides Tandem reactivity Enriched active phases

Efficacy of transjugular intrahepatic portosystemic shunts in treating cirrhotic esophageal-gastric variceal bleeding

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 471-480页

作者： Xiao-Gang Hu Jian-Ji dai Jun lu Gang Li Jia-Min Wang Yi Deng Rui Feng Kai-Ping lu Department of Interventional Radiology The Affiliated Jinhua HospitalZhejiang University School of MedicineJinhua 321000Zhejiang ProvinceChina Department of Interventional Medicine Zhejiang Provincial People’s HospitalPeople’s Hospital of Hangzhou Medical CollegeHangzhou 310000Zhejiang ProvinceChina Department of Vascular Surgery Zhejiang Provincial People’s HospitalPeople’s Hospital of Hangzhou Medical CollegeHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Esophageal-gastric variceal bleeding(EGVB)represents a severe complication among patients with cirrhosis and often culminates in fatal outcomes.Interven-tional therapy,a rapidly developing treatment modality over the past few years,has found widespread application in clinical practice due to its minimally inva-sive characteristics.However,whether transjugular intrahepatic portosystemic shunt(TIPS)treatment has an impact on patient prognosis remains controversial.METHODS A retrospective study was conducted on ninety-two patients presenting with cirrhotic EGVB who were admitted to our hospital between September 2020 and September 2022.Based on the different modes of treatment,the patients were assigned to the study group(TIPS received,n=50)or the control group(per-cutaneous transhepatic varices embolization received,n=42).Comparative ana-lyses were performed between the two groups preoperatively and one month postoperatively for the following parameters:Varicosity status;hemodynamic parameters[portal vein flow velocity(PVV)and portal vein diameter(PVD);platelet count(PLT);red blood cell count;white blood cell count(WBC);and hepatic function[albumin(ALB),total bilirubin(TBIL),and aspartate transaminase(AST)].The Generic Quality of Life Inventory-74 was utilized to assess quality of life in the two groups,and the 1-year postoperative rebleeding and survival rates were compared.RESULTS Following surgical intervention,there was an improvement in the incidence of varicosity compared to the preoperative status in both cohorts.Notably,the study group exhibited more pronounced enhancements than did the control group(Plues,with the study cohort achieving better outcomes(P<0.05).PLT and WBC counts were elevated postoperatively in the two groups,with the study cohort displaying higher PLT and WBC counts(P<0.05).No differences were detected between the two groups in terms of serum ALB,TBIL,or AST levels either preoperatively or postoperatively(P<0

关键词： Liver cirrhosis Esophagogastric variceal bleeding Transjugular intrahepatic portosystemic shunt Prognosis