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Molecular Dynamics Simulation of Shock Response of CL-20 Co-crystals Containing Void Defects

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Defence Technology（防务技术） 2024年第1期31卷 364-374页

作者： Changlin Li wei Yang Qiang Gan Yajun Wang Lin Liang Wenbo Zhang Shuangfei zhu Changgen Feng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Materials Science&Engineering Beijing Institute of TechnologyBeijing 100081China

To investigate the effect of void defects on the shock response of hexanitrohexaazaisowurtzitane(CL-20)co-crystals,shock responses of CL-20 co-crystals with energetic materials ligands trinitrotoluene(TNT),1,3-dinitrobenzene(DNB),solvents ligands dimethyl carbonate(DMC) and gamma-butyrolactone(GBL)with void were simulated,using molecular dynamics method and reactive force field.It is found that the CL-20 co-crystals with void defects will form hot spots when impacted,significantly affecting the decomposition of molecules around the void.The degree of molecular fragmentation is relatively low under the reflection velocity of 2 km/s,and the main reactions are the formation of dimer and the shedding of nitro groups.The existence of voids reduces the safety of CL-20 co-crystals,which induced the sensitivity of energetic co-crystals CL-20/TNT and CL-20/DNB to increase more significantly.Detonation has occurred under the reflection velocity of 4 km/s,energetic co-crystals are easier to polymerize than solvent co-crystals,and are not obviously affected by voids.The results show that the energy of the wave decreases after sweeping over the void,which reduces the chemical reaction frequency downstream of the void and affects the detonation performance,especially the solvent co-crystals.

关键词： CL-20 co-crystals Molecular dynamics simulation Reactive forcefield Impact response Hot spot Void defect

Effects of ulinastatin combined with dexmedetomidine on cognitive dysfunction and emergence agitation in elderly patients who underwent total hip arthroplasty

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World Journal of Psychiatry 2024年第1期14卷 26-35页

作者： Qi-Fan Huo Li-Juan zhu Jian-wei Guo Yan-An Jiang Jing Zhao Department of Anesthesiology Shaanxi Provincial People’s HospitalXi’an 710068Shaanxi ProvinceChina

BACKGROUND With the continuous growth of the modern elderly population,the risk of fracture increases.Hip fracture is a common type of fracture in older people.Total hip arthroplasty(THA)has significant advantages in relieving chronic pain and promoting the recovery of hip joint function.AIM To investigate the effect of ulinastatin combined with dexmedetomidine(Dex)on the incidences of postoperative cognitive dysfunction(POCD)and emergence agitation in elderly patients who underwent THA.METHODS A total of 397 patients who underwent THA from February 2019 to August 2022.We conducted a three-year retrospective cohort study in Shaanxi Provincial People’s Hospital.Comprehensive demographic data were obtained from the electronic medical record system.We collected preoperative,intraoperative,and postoperative data.One hundred twenty-nine patients who were administered Dex during the operation were included in the Dex group.One hundred fifty patients who were intravenously injected with ulinastatin 15 min before anesthesia induction were included in the ulinastatin group.One hundred eighteen patients who were administered ulinastatin combined with Dex during the operation were included in the Dex+ulinastatin group.The patients’perioperative conditions,hemodynamic indexes,postoperative Mini-Mental State Examination(MMSE)scores,Ramsay score,incidence of POCD,and serum inflammatory cytokines were evaluated.RESULTS There was a significant difference in the 24 h visual analogue scale score among the three groups,and the score in the Dex+ulinastatin group was the lowest(P<0.05).Compared with the Dex and ulinastatin group,the MMSE scores of the Dex+ulinastatin group were significantly increased at 1 and 7 d after the operation(all P<0.05).Compared with those in the Dex and ulinastatin groups,incidence of POCD,levels of serum inflammatory cytokines in the Dex+ulinastatin group were significantly decreased at 1 and 7 d after the operation(all P<0.05).The observer’s assessment of the alertness/sedation score and Ramsay score of t

关键词： Ulinastatin Dexmedetomidine Postoperative cognitive dysfunction Inflammatory cytokines Total hip arthroplasty

Ultrathin and flexible MXene-contained electromagnetic interference shielding composite paper designed with a protective hydrogel film

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Journal of Materials Science & Technology 2024年第2期169卷 199-208页

作者： Jiasheng wei Lei Dai Ping He Meng zhu Feng Jiang Zhaoxiang Zhou Guiqiang Fei Tingzhou Lei College of Bioresources Chemical and Materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China Key Laboratory of Eco-Textiles Ministry of EducationJiangnan UniversityWuxi 214122China Zhejiang Shunpu New Material Technology Co. LtdLongyou 324404China College of Chemistry and Chemical Engineering Shaanxi University of Science and TechnologyXi’an 710021China National-Local Joint Engineering Research Center of Biomass Refining and High-Quality Utilization Institute of Urban and Rural MiningChangzhou UniversityChangzhou 213164China

MXene-contained paper is a good choice to design ultrathin and flexible electromagnetic interference(EMI)shielding materials.However,the deficiencies in strength and stability of MXene-contained paper impede its practical applications.Herein,a composite paper was proposed to address the problems,in which a filter paper was modified with a three-layer structured surface via a facile layer-by-layer coating procedure.Specifically,the TEMPO-oxidized cellulose nanofibers(TOCN)/cationic starch(CS)/MXene gel layer and TOCN/MXene nacre structure layer ensured the good EMI shielding and mechanical performances of the composite paper,while the uppermost TOCN/CS hydrogel film layer mainly protected MXene.The composite paper achieved an EMI SE of 40.3 dB at a thickness of merely 0.1894 mm(SE/t value of ca.212.8 dB mm^(−1),SSE/t values of ca.13216 dB cm 2 g^(−1))and the total MXene dosage was 20 g m^(−2).Its tensile strength could be up to 11.7 MPa while the original filter paper was 6.4 MPa.Four pieces of this composite papers could be easily packed together to attain an EMI SE of nearly 70 dB.Importantly,the hydrogel film layer efficiently protected the MXene and maintained the EMI shielding performance of the composite paper when immersed in different liquids including water,HCl(1 M)and ethanol,due to the dense and compact structure of hydrogel film layer.This work provides a practical way to develop ultrathin,flexible and durable EMI shielding materials.

关键词： MXene Electromagnetic interference shielding Nanocellulose Hydrogel

Asymptotic Inference in the Random Coefficient Autoregressive Model with Time-functional Variance Noises

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 320-346页

作者： En-wen zhu Zi-wei DENG Han-jun ZHANG Jun CAO Xiao-hui LIU Department of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China School of Statistics and Data Science and Key Laboratory of Data Science in Finance and EconomicsJiangxi University of Finance and EconomicsNanchang 330013China

This paper considers the random coefficient autoregressive model with time-functional variance noises,hereafter the RCA-TFV model.We first establish the consistency and asymptotic normality of the conditional least squares estimator for the constant coefficient.The semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed,and their asymptotic results are reported.A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.

关键词： random coefficient autoregressive model time-functional variance conditional least squares semiparametric least squares

Symmetry breaking of highly symmetrical nanoclusters for triggering highly optical activity

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Fundamental Research 2024年第1期4卷 63-68页

作者： Xiao wei Hao Li Honglei Shen Chuanjun Zhou Shuxin Wang Xi Kang Manzhou zhu Department of Chemistry and Centre for Atomic Engineering of Advanced Materials Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationInstitutes of Physical Science and Information Technology and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials.Anhui UniversityHefei 230601China

Developing new approaches to fulfill the enantioseparation of nanocluster racemates and construct cluster-based nanomaterials with optical activity remains highly desired in cluster science,because it is an essential prerequisite for fundamental research and extensive applications of these nanomaterials.We herein propose a strategy termed“active-site exposing and partly re-protecting”to trigger the symmetry breaking of highly symmetrical nanoclusters and to render cluster crystals optically active.The vertex PPh_(3)of the symmetrical Ag_(29)(SSR)_(12)(PPh_(3))_(4)(SSR=1,3-benzenedithiol)nanocluster was firstly dissociated in the presence of counterions with large steric hindrance,and then the exposed Ag active sites of the obtained Ag_(29)(SSR)_(12)nanocluster were partly re-protected by Ag^(+),yielding an Ag_(29)(SSR)_(12)-Ag_(2)nanocluster with a symmetry-breaking construction.Ag_(29)(SSR)_(12)-Ag_(2)followed a chiral crystallization mode,and its crystal displayed strong optical activity,derived from CD and CPL characterizations.Overall,this work presents a new approach(i.e.,active-site exposing and partly re-protecting)for the symmetry breaking of highly symmetrical nanoclusters,the enantioseparation of nanocluster racemates,and the achievement of highly optical activity.

关键词： Atomically precise nanocluster Symmetry breaking Enantioseparation Circularly polarized luminescent Photoluminescence

Development and applications of the quasi‐dynamic triaxial apparatus for deep rocks

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Deep Underground Science and Engineering 2024年第1期3卷 70-90页

作者： Jinzhi Luo Yanyan Cai Jin Yu Jianzhi Zhang Yaoliang zhu Yao wei School of Civil Engineering Huaqiao UniversityXiamenFujianChina Zijin School of Geology and Mining Fuzhou UniversityFuzhouChina

The mechanical behaviors of deep rocks have always posed a challenge for the implementation and safe operation of major underground engineering projects.To this end,this study modified the existing mainstream rock mechanics instruments equipped with a dynamic disturbance loading system and developed a second‐generation TFD‐2000/D triaxial instrument.The first‐generation device is equipped with an independent disturbance system and an advanced EDC‐580 all‐digital servo controller,which can apply disturbing load independently,implement the function of cyclic disturbance,and combine dynamic and static disturbances.The instrument was found to be reliable for use in analyzing the damage process of rocks in the disturbance test of marbles.The second‐generation instrument tackles three limitations of the first‐generation instrument:(i)it upgrades the strain measurement system and uses extensometers with linear variable differential transformers to accurately measure deformation;(ii)it uses the self‐balanced chamber to replace the Hoek–Franklin triaxial cell and auto‐balancing triaxial pressure chamber;and(iii)the loading rod is independently equipped with an EDC‐580 all‐digital servo controller,which measures precise loads.The experimental findings confirmed that the second‐generation instrument can be used for rock mechanics testing under cyclic disturbance loading,the disturbance–stress relaxation cycle,and the creep–fatigue cycle.In this sense,the second‐generation instrument can be a useful addition to deep rock mechanical instruments and provide a valuable reference.

关键词： complex stress conditions deep rock disturbance loading modification of instrument rock mechanics

Chinese version of the Perth Alexithymia Questionnaire:psychometric properties and clinical applications

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General Psychiatry 2024年第2期37卷 274-283页

作者： Xin-Lu Cai Qingying Ye Ke Ni Lin zhu Qian Zhang Minmin Yin Zhe Zhang wei wei David A.Preece Bao-Ming Li Institute of Brain Science and Department of Physiology School of Basic Medical SciencesHangzhou Normal UniversityHangzhouZhejiangChina Zhejiang Philosophy and Social Science Laboratory for Research in Early Development and Childcare Hangzhou Normal UniversityHangzhouZhejiangChina Qiqihar Mental Health Center QiqiharChina Department of Special Education Faculty of EducationHangzhou Normal UniversityHangzhouZhejiangChina Department of Neurobiology Affiliated Mental Health Center&Hangzhou Seventh People's Hospital Zhejiang University School of MedicineHangzhouZhejiangChina Liangzhu Laboratory MOE Frontier Science Center for Brain Science and Brain-machine IntegrationState Key Laboratory of Brain-machine IntelligenceZhejiang UniversityHangzhouZhejiangChina NHC and CAMS Key Laboratory of Medical Neurobiology Zhejiang UniversityHangzhouChina School of Population Health and Curtin enAble Institute Curtin UniversityPerthWestern AustraliaAustralia School of Psychological ScienceThe University of Western AustraliaPerthWestern AustraliaAustralia

Background The alexithymia trait is of high clinical interest.The Perth Alexithymia Questionnaire(PAQ)was recently developed to enable detailed facet-level and valence-specific assessments of alexithymia.Aims In this paper,we introduce the first Chinese version of the PAQ and examine its psychometric properties and clinical applications.Methods In Study 1,the PAQ was administered to 990 Chinese participants.We examined its factor structure,internal consistency,test-retest reliability,as well as convergent,concurrent and discriminant validity.In Study 2,four groups,including a major depressive disorder(MDD)group(n=50),a matched healthy control group for MDD(n=50),a subclinical depression group(n=50)and a matched healthy control group for subclinical depression(n=50),were recruited.Group comparisons were conducted to assess the clinical relevance of the PAQ.Results In Study 1,the intended five-factor structure of the PAQ was found to fit the data well.The PAQ showed good internal consistency and test-retest reliability,as well as good convergent,concurrent and discriminant validity.In Study 2,the PAQ was able to successfully distinguish the MDD group and the subclinical depression group from their matched healthy controls.Conclusions The Chinese version of the PAQ is a valid and reliable instrument for comprehensively assessing alexithymia in the general population and adults with clinical/subclinical depression.

关键词： clinical instrument matched

Gradient sparsification for efficient wireless federated learning with differential privacy

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Science China(Information Sciences) 2024年第4期67卷 272-288页

作者： Kang wei Jun LI Chuan MA Ming DING Feng SHU Haitao ZHAO Wen CHEN Hongbo zhu School of Electronic and Optical Engineering Nanjing University of Science and Technology Zhejiang Lab Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of Education Data61 Commonwealth Scientific and Industrial Research Organisation School of Information and Communication Engineering Hainan University School of Communications and Information Engineering Nanjing University of Posts and Telecommunications School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

Federated learning(FL) enables distributed clients to collaboratively train a machine learning model without sharing raw data with each other. However, it suffers from the leakage of private information from uploading models. In addition, as the model size grows, the training latency increases due to the limited transmission bandwidth and model performance degradation while using differential privacy(DP)protection. In this paper, we propose a gradient sparsification empowered FL framework with DP over wireless channels, to improve training efficiency without sacrificing convergence performance. Specifically, we first design a random sparsification algorithm to retain a fraction of the gradient elements in each client’s local model, thereby mitigating the performance degradation induced by DP and reducing the number of transmission parameters over wireless channels. Then, we analyze the convergence bound of the proposed algorithm, by modeling a non-convex FL problem. Next, we formulate a time-sequential stochastic optimization problem for minimizing the developed convergence bound, under the constraints of transmit power, the average transmitting delay, as well as the client’s DP requirement. Utilizing the Lyapunov drift-plus-penalty framework, we develop an analytical solution to the optimization problem. Extensive experiments have been implemented on three real-life datasets to demonstrate the effectiveness of our proposed algorithm. We show that our proposed algorithms can fully exploit the interworking between communication and computation to outperform the baselines, i.e., random scheduling, round robin, and delay-minimization algorithms.

关键词： federated learning differential privacy gradient sparsification Lyapunov drift convergence analysis

Phosphotungstic acid ionic liquid for efficient photocatalytic desulfurization:Synthesis,application and mechanism

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Chinese Journal of Chemical Engineering 2024年第5期69卷 101-111页

作者： Chenchao Hu Suhang Xun Desheng Liu Junjie Zhang Minqiang He wei Jiang Huaming Li Wenshuai zhu Institute of Environmental Health and Ecological Security School of Environment and Safety EngineeringJiangsu UniversityZhenjiang 212013China School of Chemistry and Chemical Engineering Institute for Energy ResearchJiangsu UniversityZhenjiang 212013China Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment Suzhou University of Science and TechnologySuzhou 215009China

An efficient mass transfer process is a critical factor for regulating catalytic activity in a photocatalytic desulfurization system.Herein,a phosphotungstic acid(HPW)active center is successfully composited with a quaternary ammonium phosphotungstate-based hexadecyltrimethylammonium chloride ionic liquid(CTAC-HPW)by the ion exchange method for the photocatalytic oxidative desulfurization of dibenzothiophene sulfide.The keggin structure of HPW and highly mass transfer performance of organic cations synergistically enhanced the photocatalytic activity towards the effective convertion of dibenzothiophene(DBT)with the excitation of visible light.The deep desulfurization(<10 mg·kg^(-1))is attained within 30 min,and well stability is demonstrated within 25 cycles.Moreover,the CTAC-HPW photocatalyst projects well selectivity to interference from coexisting compounds such as olefins and aromatic hydrocarbons and universality of dibenzothiophenes,for example,4-methyldibenzothiophene(4-MDBT)and 4,6-dimethyldibenzothiophene(4,6-DMDBT).Ultimately,a possible photocatalytic desulfurization mechanism is proposed according to the Gaschromatography-mass spectrometry(GC-MS),proving that the final product is the corresponding sulfone.The trapping experiment and electron spin resonance(ESR)analysis confirmed that h^(+)and,COOH played critical roles in the oxidation process.The work offers a practicable strategy for efficiently converting DBT to DBTO_(2) with added value.

关键词： Photocatalytic desulfurization Extraction Ionic liquid CTAC-HPW