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Theoretical analysis and numerical simulation of acoustic waves in gas hydrate-bearing sediments

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Chinese Physics B 2021年第2期30卷 344-354页

作者： Lin Liu xiu-mei zhang xiu-Ming Wang State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100149China Beijing Engineering Research Center of Sea Deep Drilling and Exploration Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Based on Carcione-Leclaire model,the time-splitting high-order staggered-grid finite-difference algorithm is proposed and constructed for understanding wave propagation mechanisms in gas hydrate-bearing *** compressional waves and two shear waves,as well as their energy distributions are investigated in *** particular,the influences of the friction coefficient between solid grains and gas hydrate and the viscosity of pore fluid on wave propagation are *** results show that our proposed numerical simulation algorithm proposed in this paper can effectively solve the problem of stiffness in the velocity-stress equations and suppress the grid dispersion,resulting in higher accuracy compared with the result of the Fourier pseudospectral method used by *** excitation mechanisms of the five wave modes are clearly revealed by the results of ***,it is pointed that,the wave diffusion of the second kind of compressional and shear waves is influenced by the friction coefficient between solid grains and gas hydrate,while the diffusion of the third compressional wave is controlled by the fluid ***,two fluid-solid(gas-hydrate formation)models are constructed to study the mode conversion of various *** results show that the reflection,transmission,and transformation of various waves occur on the interface,forming a very complicated wave field,and the energy distribution of various converted waves in different phases is *** is demonstrated from our studies that,the unconventional waves,such as the second and third kinds of compressional waves may be converted into conventional waves on an *** propagation mechanisms provide a concrete wave attenuation explanation in inhomogeneous media.

关键词： gas hydrate-bearing sediments Carcione-Leclaire model time-splitting staggered-grid finite-difference slow-wave characteristics

Generalized collar waves in acoustic logging while drilling

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Chinese Physics B 2016年第12期25卷 118-120页

作者：王秀明何晓张秀梅 State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences

Tool waves, also named collar waves, propagating along the drill collars in acoustic logging while drilling （ALWD）, strongly interfere with the needed P- and S-waves of a penetrated formation, which is a key issue in picking up formation P- and S-wave velocities. Previous studies on physical insulation for the collar waves designed on the collar between the source and the receiver sections did not bring to a satisfactory solution. In this paper, we investigate the propagation features of collar waves in different models. It is confirmed that there exists an indirect collar wave in the synthetic full waves due to the coupling between the drill collar and the borehole, even there is a perfect isolator between the source and the receiver. The direct collar waves propagating all along the tool and the indirect ones produced by echoes from the borehole wall are summarized as the generalized collar waves. Further analyses show that the indirect collar waves could be relatively strong in the full wave data. This is why the collar waves cannot be eliminated with satisfactory effect in many cases by designing the physical isolators carved on the tool.

关键词： acoustic logging while drilling borehole wave propagation generalized collar waves indirectcollar waves

Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao zhang Yu-Hai zhang Ying Zou xiu-xiu Yang Gen zhang Feng-Shou zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

Optimizing surgical outcomes for elderly gallstone patients with a high body mass index using enhanced recovery after surgery protocol

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World Journal of Gastrointestinal Surgery 2023年第10期15卷 2191-2200页

作者： Yue-Xia Gu Xin-Yu Wang Yang Chen Jun-xiu Shao Shen-Xian Ni xiu-mei zhang Si-Yu Shao Yu zhang Wen-Jing Hu Ying-Ying Ma Meng-Yao Liu Hua Yu Department of Nursing Shanghai Fourth People’s Hospital Affiliated to Tongji University School of MedicineShanghai 200434China Department of General Surgery Shanghai Fourth People’s Hospital School of Medicine Tongji UniversityShanghai 200434China Department of Nursing Shanghai Xuhui Central HospitalShanghai 200031China

BACKGROUND Rehabilitation of elderly patients with a high body mass index(BMI)after cholecystectomy carries risks and requires the adoption of effective perioperative management *** enhanced recovery after surgery(ERAS)protocol is a comprehensive treatment approach that facilitates early patient recovery and reduces postoperative *** To compare the effectiveness of traditional perioperative management methods with the ERAS protocol in elderly patients with gallbladder stones and a high *** This retrospective cohort study examined data from 198 elderly patients with a high BMI who underwent cholecystectomy at the Shanghai Fourth People's Hospital from August 2019 to August *** them,99 patients were managed using the traditional perioperative care approach(non-ERAS protocol),while the remaining 99 patients were managed using the ERAS *** indicator data were collected for patients preoperatively,intraoperatively,and postoperatively,and surgical outcomes were compared between the two *** The comparison results between the two groups of patients in terms of age,sex,BMI,underlying diseases,surgical type,and preoperative hospital stay showed no statistically significant ***,the ERAS group had a significantly shorter preoperative fasting time than the non-ERAS group(4.0±0.9 h vs 7.6±0.9 h).Regarding intraoperative indicators,there were no significant differences between the two groups of ***,in terms of postoperative recovery,the ERAS protocol group exhibited significant advantages over the non-ERAS group,including a shorter hospital stay,lower postoperative pain scores and postoperative hunger scores,and higher satisfaction *** readmission rate was lower in the ERAS protocol group than in the non-ERAS group(3.0%vs 8.1%),although the difference was not ***,there were significant differences between the two groups in terms of postoperative nausea and vomit

关键词： Enhanced recovery after surgery protocol Cholecystectomy Rehospitalization rate Postoperative nausea and vomiting Degree of abdominal distension Daily living ability

A bifunctional POM-based Cu-viologen complex with mixed octamolybdate clusters for rapid oxidation desulfurization and effective photogeneration of hydrogen

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Rare Metals 2024年第1期43卷 236-246页

作者： Lin Yang Zhong zhang Chao-Nan zhang xiu-Li Wang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar Cell Bohai UniversityJinzhou 121013China

The design and synthesis of catalysts for the oxidation desulfurization and production of hydrogen are extremely important for solving environmental pollution and energy ***,a novel bifunctional [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)-based Cu-viologen complex H_(4)[Cu_(2)~ⅠCl_(2)(Hbcbpy)_(4)] [α-Mo_(8)O_(26)] [β-Mo8O_(26)]·H_(2)O(BHU-2,Hbcbpy=1-(4-carboxybenzyl)-4,4'-bipyridinium) was synthesized and characterized by single-crystal X-ray diffraction(XRD),infrared radiation spectra,powder X-ray diffraction(PXRD) and X-ray photoelectron spectroscopy(XPS) *** structural characteristic of BHU-2 is the presence of two types of octamolybdate clusters [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)and a new binuclear Cu~Ⅰ-Hbcbpy complex linked by Cl-bridges[Cu_(2)ⅠCl_(2)(Hbcbpy)_(4)]^(4+).BHU-2 as a heterogeneous catalyst exhibits excellent activities to the oxidation desulfurization and photocatalytic hydrogen *** room temperature,BHU-2 can catalyze 96% conversion of methyl phenyl sulfide with 98% selectivity,and the process obeys the pseudo-first-order reaction kinetic with the half-life of9.6 *** notorious 2-chloroethyl ethyl sulfide can achieve 99% conversion with 98% selectivity within only1 min at the presence of BHU-2,and the turnover frequency(TOF) is up to 7400 h^(-1).BHU-2 also exhibits high catalytic activity for the oxidation of other aromatic and aliphatic thioethers within short time at room ***,BHU-2 shows a high catalytic activity for visible-light-driven hydrogen evolution with an H_(2) evolution rate of 1677.85 μmol·g^(-1)·h^(-1) within 10 ***,the catalytic activities do not decrease evidently after three cycles,revealing the prominent structural stability and recyclability.

关键词： Polyoxometalate Metal-organic complex Viologen Oxidation desulfurization Photocatalytic hydrogen production

Reachable Set Estimation of a class of Human-in-the-Loop Control Systems

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Reachable Set Estimation of a class of Human-in-the-Loop Con...

Characterizations of semihoops based on derivations

第40届中国控制会议

作者： xiu-mei zhang Huai-Ning Wu Science and Technology on Aircraft Control Laboratory School of Automation Science and Electrical EngineeringBeihang University

This paper studies the reachable set estimation problem of a class of human-in-the-loop（Hi TL） control systems described by a controlled hidden Markov jump model. Our aim is to determine an ellipsoid-like set which bounds all the machine state trajectories of the Hi TL system under zero initial condition. By using a stochastic Lyapunov functional, a reachable set estimation condition is established, which is provided in terms of a set of matrix inequalities. Finally, an example is given to show the effectiveness of the proposed result.

关键词： Human-in-the-loop control system Markov jump system reachable set estimation stochastic Lyapunov functional

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 291-310页

作者： WANG mei zhang Xiao-hong School of Electrical and Control Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Arts and Sciences Shaanxi University of Science and TechnologyXi'an 710021China School of Mathematics and Statistics Weinan Normal UniversityWeinan 714099China

In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of ***,we prove that every Heyting algebra is isomorphic to the algebra of all multiplicative derivations and show that every Boolean algebra is isomorphic to the algebra of all implicative ***,we show that the sets of multiplicative and implicative derivations on bounded regular idempotent semihoops are in oneto-one correspondence.

关键词： (prelinear)semihoop derivation Heyting algebra Galois connection

Study on carbon emission calculation method and carbon reduction indexes of urban building stock

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Science China(Technological Sciences) 2024年第9期67卷 2706-2726页

作者： YANG Liu zhang Nan LU mei LUO ZhiXing DOU mei State Key Laboratory of Green Building Xi’an University of Architecture and TechnologyXi’an 710055China School of Architecture Xi’an University of Architecture and TechnologyXi’an 710055China School of Language Literature and LawXi’an University of Architecture and TechnologyXi’an 710055China School of Management Xi’an University of Architecture and TechnologyXi’an 710055China China Southwest Architectural Design and Research Institute Corp.Ltd. Chengdu 610041China

Carbon emissions associated with buildings are a major source of urban emissions. To put forward the methods and strategies to curb carbon emissions from urban building stock, it is not only necessary to establish a carbon emission calculation method for fine statistical analysis, but also to evaluate carbon emissions of urban planning schemes with applicable indexes. Currently,researches mainly focus on carbon emissions of individual buildings. When expanded to urban building stock, the calculation faces the lack of basic data, inadequate spatial analysis and unspecific carbon reduction indexes. Therefore, this study proposes a bottom-up calculation method for urban building stock, conducts spatial analysis based on carbon balance of urban grids, reveals the coupling mechanism between urban carbon reduction indexes and grid carbon emissions, and systematically establishes a carbon-reduction-oriented urban planning method that comprises calculation, analysis and evaluation, which is applied to Xi'an,China. This study provides a theoretical reference for cities to formulate carbon reduction targets and implement planning strategies by evaluating and predicting carbon emissions from urban building stock.

关键词： carbon emissions urban building stock calculation method carbon reduction index

P26 Study Pharmacology to be a Good Physician

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中国药理通讯 2006年第2期23卷 31-32页

作者： Bin zhang Zi-ying Wang Hui-qing Liu xiu-mei zhang Institute of Pharmacology School of Medicine Shandong University 44 West Wenhua Road Jinan 250012 China

Medical treatment level is related with rise and fall of nation. Medical education is one of the most important education. Pharmacology, as the main subject of medical science, is the bridge of medical and pharmaceutical sciences, as well as the bridge of preclinical and clinical medicine. With the elucidation of pathogenesis of some serious disease, new drug exploitation, research of mechanism of action and reasonable application become more and more important. As a pharmacological teacher, whether we can impart these essence to our students and whether these medical students will use very well in the future what they have learned, are l~oth challenge to battle we are facing with. Through years of teaching work, I have some comprehends about pharmacology teaching. In my opinion, we should try our best to make students grasp basic knowledge firstly because it is the basic requirements to be a qualified physician.

关键词：教育方法药理学医生学习方法