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Effect of Mouth Opening Training Stick Combined with Oral Massage on Mouth Opening Difficulty in Head and Neck Cancer Patients after Treatment
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作者 Jinhua Liu Qiong Wen 《Journal of Biosciences and Medicines》 2024年第6期43-51,共9页
Objective: To study the application effect of mouth-opening training sticks combined with oral massage on patients with mouth-opening difficulty after treatment for head and neck cancer. Methods: Using convenient samp... Objective: To study the application effect of mouth-opening training sticks combined with oral massage on patients with mouth-opening difficulty after treatment for head and neck cancer. Methods: Using convenient sampling, 60 patients with mouth-opening difficulty after treatment for head and neck cancer admitted to the Oncology Department from February 2022 to October 2023 were selected for a 2-week exercise and nursing program. The patients were divided into a control group (February 1, 2022 to November 30, 2022) and an observation group (December 1, 2022 to October 31, 2023), with 30 patients in each group. The control group underwent routine mouth-opening functional exercises combined with cork for oral support training, while the observation group underwent routine mouth-opening functional exercises combined with oral massage and mouth-opening training sticks for oral support training. The mouth-opening degree, mouth-opening difficulty level, comfort level, compliance, and quality of life were observed in both groups. Results: Before the intervention, there were no statistically significant differences in mouth-opening degree and mouth-opening difficulty level between the two groups (P > 0.05). After the intervention, the mouth-opening degree, mouth-opening difficulty level, oral comfort level, compliance, and QLICP-HN scores in the observation group were all better than those in the control group, with statistically significant differences (P < 0.05). Conclusion: The combination of mouth-opening training sticks and oral massage with mouth-opening functional exercises can effectively improve the degree of mouth-opening difficulty, enhance oral comfort, increase compliance with mouth-opening exercises, and improve quality of life. 展开更多
关键词 Head and Neck Cancer Difficulty in opening the Mouth open Mouth Training Stick Oral Massage Rehabilitation Effect
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FURTHER OPENING- UP IS KEY FOR CHINA’S HIGH-QUALITY DEVELOPMENT
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作者 Tom Fowdy 《China Report ASEAN》 2024年第1期64-64,共1页
The Central Economic Work Conference was held in Beijing from December 11 to 12.The conference discussed the plans,prospects and challenges for China’s economy heading into 2024,as well as evaluating the events of th... The Central Economic Work Conference was held in Beijing from December 11 to 12.The conference discussed the plans,prospects and challenges for China’s economy heading into 2024,as well as evaluating the events of this year.It goes without saying that 2023 has been a challenging year for countries around the world as the global context has been unsatisfactory.Various geopolitical tensions have created a rise in uncertainties which have led to reduced growth worldwide and sent many economies into stagnation.In light of the critical factors affecting the stability of the global economy,China’s primary economic goal corresponds with the promotion and sustaining of free trade. 展开更多
关键词 PROMOTION HEADING open
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National Image Construction from the Perspective of Multimodal Metaphor-A Case Study of the Opening Ceremony of the Beijing Winter Olympics
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作者 LUO Yi ZHOU Jing 《Journal of Literature and Art Studies》 2024年第4期290-294,共5页
The national image is a comprehensive concept with a distinct political feature,including the international image presented to the outside world,and also encompassing the national identity of the people.With the devel... The national image is a comprehensive concept with a distinct political feature,including the international image presented to the outside world,and also encompassing the national identity of the people.With the development of globalization,international cultural communication has become a crucial part of shaping the national image,and the opening ceremony of the Beijing Winter Olympics has become an important opportunity for China to showcase its national image to the world in the post-pandemic era.Based on Forceville’s multimodal metaphor theory,this paper examines the metaphorical phenomena contained in the performance and their functions,effects,and purposes in the construction of the national image.It is found that there are many scenes,images,and narratives in the opening ceremony,including war metaphor,competition metaphor,personification metaphor,and other conceptual metaphors.The focus of this paper is on multimodal metaphor in a broad sense,mainly encompassing auditory and visual modes.Through the use of these multimodal metaphors,the opening ceremony of the Winter Olympics builds an image of a vibrant,peace-loving,and responsible country,which not only demonstrates China’s cultural self-confidence,but also expresses the Chinese people’s beautiful vision for the early reunification of the motherland. 展开更多
关键词 multimodal metaphor national image Olympic Winter Games opening Ceremony
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CIIE to Promote High-Level Opening Up
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《ChinAfrica》 2024年第11期60-61,共2页
The 7th China International Import Expo(CIIE),scheduled to be held in Shanghai from 5 to 10 November,will play a part in promoting highlevel opening up,said Tang Wenhong,China’s assistant minister of commerce,at a pr... The 7th China International Import Expo(CIIE),scheduled to be held in Shanghai from 5 to 10 November,will play a part in promoting highlevel opening up,said Tang Wenhong,China’s assistant minister of commerce,at a press conference on 23 October.The CIIE serves to showcase China’s major opening-up measures and confidence,to share China’s new development opportunities with other countries. 展开更多
关键词 opening measures scheduled
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High complex anal fistula managed by the modified transanal opening of the intersphincteric space via the inter-sphincteric approach:A case report
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作者 Ya-Qun Wang Yan Wang +2 位作者 Xiao-Feng Jia Qiao-Jing Yan Xue-Ping Zheng 《World Journal of Radiology》 2024年第10期552-560,共9页
BACKGROUND High complex anal fistulas are epithelialized tunnels,with the main fistula piercing above the deep external sphincter and the internal opening approaching the dentate line.Conventional surgical procedures ... BACKGROUND High complex anal fistulas are epithelialized tunnels,with the main fistula piercing above the deep external sphincter and the internal opening approaching the dentate line.Conventional surgical procedures for high complex anal fistulas remove most of the external sphincter and damage the anorectal ring.Postoperative loss of anal function can cause physical and mental damage.Transanal opening of the intersphincteric space(TROPIS)is an effective procedure that completely preserves the external anal sphincter.However,its clinical application is limited by challenges in the localization of the internal opening of a fistula and the high risk of complications.On the basis of our clinical experience,we modified the TROPIS procedure for the treatment of treating high complex anal fistulas.CASE SUMMARY A patient with a high complex anal fistula located above the anorectal ring underwent modified TROPIS,which involved sepsis drainage and identification of the internal opening in the intersphincteric space.The patient with the high complex anal fistula recovered well postoperatively,without any postoperative complications or anal dysfunction.Anal function returned to normal after 17 months of follow-up.CONCLUSION The modified TROPIS procedure is the most minimally invasive surgery for anal fistulas that minimally impairs anal function.It allows the complete removal of infected anal glands and reduces the risk of postoperative complications.Modified TROPIS via the intersphincteric approach is an alternative sphincter-preserving treatment for high complex anal fistulas. 展开更多
关键词 High complex anal fistula Inter-sphincteric infection Trans-anal opening of inter-sphincteric space PERIANAL Pelvic magnetic resonance imaging Anal function protection Case report
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Stomatal Opening Induced by Acetylcholine Is Associated with Cytoskeletal Components 被引量:2
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作者 黄荣峰 王学臣 娄成后 《Acta Botanica Sinica》 CSCD 2000年第6期559-563,共5页
Acetylcholine (Ach) is a key component of animal cholinergic system. Recent experiments demonstrated that Ach, choline acetyltransferase, acetylcholinesterase and Ach receptors are present in all parts of plants and... Acetylcholine (Ach) is a key component of animal cholinergic system. Recent experiments demonstrated that Ach, choline acetyltransferase, acetylcholinesterase and Ach receptors are present in all parts of plants and have many functions, including inducing stomatal movement. The authors' previous work has evidenced that microtubules and microfilaments are involved in regulating both stomatal closing and opening. The present investigation is to determine whether stomatal opening induced by Ach is associated with microtubules and microfilaments. The results showed that Ach could induce stomatal opening of Vicia faba L. with or without addition of KCl in the dark. Ach also stimulated protoplast swelling in a K +_free solution in the dark. However, the induction was partially suppressed when the strips and protoplasts were pretreated with either cytochalasin B, an inhibitor of F_actin polymerization, or oryzalin, an inhibitor of plant microtubule polymerization. Thus, our data suggest for the first time that stomatal opening induced by Ach is associated with the dynamics of microtubules and microfilaments. 展开更多
关键词 MICROTUBULE MICROFILAMENT ACETYLCHOLINE Vicia faba stomatal opening
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一种基于改进path opening的道路提取新方法 被引量:8
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作者 王双 曹国 《计算机科学》 CSCD 北大核心 2014年第2期285-289,共5页
提出了一种基于改进path opening的高分辨率遥感影像道路提取新方法。为检测曲率较大的道路,构造了新的邻接图;为有效提取有损或有部分遮挡的道路,将path opening算法中的最大路径长度与区域的几何特征相结合,建立了道路区域的判定准则... 提出了一种基于改进path opening的高分辨率遥感影像道路提取新方法。为检测曲率较大的道路,构造了新的邻接图;为有效提取有损或有部分遮挡的道路,将path opening算法中的最大路径长度与区域的几何特征相结合,建立了道路区域的判定准则,减少了人工干预。通过多组实验结果证明,该方法对于不完整道路的提取有更好的效果。 展开更多
关键词 PATH opening 有损道路 道路提取 几何特征
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Opening Moves Involved in Text-based Computer-Mediated-Communication (CMC) by Chinese Adults
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作者 李莉华 《海外英语》 2011年第3X期257-258,260,共3页
The development of science and technology has made it not only possible but very convenient for people living in different parts of the world to communicate with each other, thus bringing forth a new form of communica... The development of science and technology has made it not only possible but very convenient for people living in different parts of the world to communicate with each other, thus bringing forth a new form of communication: computer-mediated communication (CMC). Text-based CMC is one of the most popular forms of CMC in which people send instant messages to others in different settings. Since this mode of interaction combines features of both the written and spoken language (Greenfield & Subrahmanyam, 2003), it's of great interest whether it follows the same sequential rule as the telephone conversation. However, compared to telephone conversations, computer-mediated communication has received much less attention, let alone text-based CMC. The existing body of literature mostly focuses on content analysis and linguistic features but neglects the sequential organization of such interaction (Paolillo, 1999; Greenfield and Subrahmanyam, 2003; Herring, 1999). In light of this, this paper examines the opening moves of instant message exchanges among Chinese adults in an attempt to find out the unique features characterizing the way they open an online chat. The framework that was chosen for data analysis was the sequential model proposed by Schegloff for American telephone openings. 展开更多
关键词 computer-mediated communication(CMC) Text-based CMC opening MOVES instant message exchanges on line chat sequential model
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Investigating the mechanical and acoustic emission characteristics of brittle failure around a circular opening under uniaxial loading 被引量:10
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作者 Peng Li Fen-hua Ren +3 位作者 Mei-feng Cai Qi-feng Guo Hao-fei Wang Kang Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第10期1217-1230,共14页
The size of underground openings in rock masses in metal mines is critical to the performance of the openings. In this study, the mechanical and acoustic emission (AE) characteristics of brittle rock-like specimens co... The size of underground openings in rock masses in metal mines is critical to the performance of the openings. In this study, the mechanical and acoustic emission (AE) characteristics of brittle rock-like specimens containing a circular opening with different ratios of opening diameter to sample size λ (λ = 0.1, 0.13, 0.17, 0.2, and 0.23) were investigated under uniaxial compression with AE monitoring. The results indicate that the opening size strongly affected the peak strength and the elastic modulus. Crack initiation first started from the upper surface of the specimens, not from the periphery of the openings. Tensile and shear cracks coexisted on the roof and floor of the specimens, whereas tensile cracks were dominant on the two sides. The fracture mode of samples with openings was partially affected by the relative size of the pillars and openings. The AE response curves (in terms of counts, cumulative energy, cumulative counts, and b-value) show that brittle failure was mainly a progressive process. Moreover, the AE information corresponded well with microcrack evolution in the samples and thus can be used to predict sample failure. 展开更多
关键词 ROCK MECHANICS CIRCULAR opening opening size UNIAXIAL compression acoustic emission
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Study on transient aerodynamic characteristics of parachute opening process 被引量:20
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作者 Li Yu Xiao Ming 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第6期627-633,共7页
In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficu... In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficulty for theoretical analysis and experimental measurements. In this paper, aerodynamic equations and structural dynamics equations were developed for describing parachute opening process, and an iterative coupling solving strategy incorpo- rating the above equations was proposed for a small-scale, flexible and flat-circular parachute. Then, analyses were carried out for canopy geometry, time-dependent pressure difference between the inside and outside of the canopy, transient vortex around the canopy and the flow field in the radial plane as a sequence in opening process. The mechanism of the canopy shape development was explained from perspective of transient flow fields during the inflation process. Experiments of the parachute opening process were conducted in a wind tunnel, in which instantaneous shape of the canopy was measured by high velocity camera and the opening loading was measured by dynamometer balance. The theoretical predictions were found in good agreement with the experimental results, validating the proposed approach. This numerical method can improve the situation of strong dependence of parachute research on wind tunnel tests, and is of significance to the understanding of the mechanics of parachute inflation process. 展开更多
关键词 PARACHUTE opening process Numerical simulation Flow field characteristics AERODYNAMICS Structural dynamics
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Opening Angle Rules of the Aerodynamic Brake Panel 被引量:7
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作者 高立强 奚鹰 +2 位作者 王国华 张攀 左建勇 《Journal of Donghua University(English Edition)》 EI CAS 2016年第1期20-24,共5页
In order to get the relationship between aerodynamic brake effect and the opening angle,based on a high-speed train model in CFD software FLUENT,the aerodynamic force properties from brake panels with different openin... In order to get the relationship between aerodynamic brake effect and the opening angle,based on a high-speed train model in CFD software FLUENT,the aerodynamic force properties from brake panels with different opening angles were analyzed as well as the flow field's variation laws. Six cases were researched,taking opening angles 45°,60°,75°,80°,85° and 90° respectively.Three-dimensional Reynolds-average Navier-Stokes equation combined with k-ε turbulence model was utilized. The control equation was discretized and solved by finite volume method.SIMPLE method was also considered to couple the pressure and velocity fields and search the numeric solutions. Conclusions can be achieved from the results which are shown as follows. When the opening angle increases from 45° to 75°,the aerodynamic forces and the central area with larger pressure increase fast,and the flow field distribution changes greatly; when the opening angle increases from75° to 90°,the aerodynamic forces and the central area with larger pressure increase slowly, and the flow field distribution changes slightly; considering train boundary and opening performance of the wind resistance brake mechanism,the opening angle should be 75°. 展开更多
关键词 BRAKE PANEL RULE of opening angle aerodynamic BRAKE high-speed TRAIN
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Periodical zonal character of damage near the openings inhighly-stressed rock mass conditions 被引量:4
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作者 Vladimir VMakarov Mikhail AGuzev +1 位作者 Vladimir NOdintsev Lyudmila SKsendzenko 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第2期164-169,共6页
Rock mass damage at great depths near underground openings is often of a zonal character.However,the classical elastoplastic theory fails to explain sufficiently all properties of zonal failure structures.A new non-Eu... Rock mass damage at great depths near underground openings is often of a zonal character.However,the classical elastoplastic theory fails to explain sufficiently all properties of zonal failure structures.A new non-Euclidean mathematical model for highly-stressed rock mass was developed based on the principles of mechanics of defected material and non-equilibrium thermodynamics.Methods were developed to determine model parameters that provide satisfactory correspondence between the experimental findings concerning faulted zonal structures near openings at great depths and mathematical calculations.The mechanism of this phenomenon was discovered which consisted in a periodical character of stresses in the surrounding rock mass and development of tensile macrocracks at zones of maximal tangential stresses.Main relationships between the cracking zone width and rock mass strength were established. 展开更多
关键词 Rock failure openingS ZONES Modeling
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CATIONIC RING-OPENING POLYMERIZATION OF TETRAHYDROFURAN WITH KEGGIN-TYPE HETEROPOLYCOMPOUNDS AS SOLID ACID CATALYSTS 被引量:4
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作者 Ahmed Aouissi Salim Salem Al-Deyab Hassan Al-Shehri 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第3期305-310,共6页
Three Keggin-type heteropolyanions, namely H3PMo12O40-13H2O, (NH4)3PMo12O40·4H2O and H3PW12O40·13H2O were prepared and tested in the ring-opening polymerization reaction of tetrahydrofuran. The effects of ... Three Keggin-type heteropolyanions, namely H3PMo12O40-13H2O, (NH4)3PMo12O40·4H2O and H3PW12O40·13H2O were prepared and tested in the ring-opening polymerization reaction of tetrahydrofuran. The effects of the counter-cation (H+, NH4+) and the peripheral atoms (Mo, W) on the polymerization were investigated. It has been found that when the protons of H3PMo12O40·13H2O were replaced by the ammonium cations the polymerization rate decreased dramatically. Whereas, when the peripheral atoms (Mo) were replaced by their homologous (W), the polymerization rate increased twofold. As for the viscosity average molecular weight (My) of polymer products, it was found that the high molecular weight (7930) was obtained by using H3PW12O40·13H2O. The molecular weight (My) obtained by H3PMo12O40·13H2O and (NH4)H3PMo12O40·13H2O was 6470 and 6810, respectively. 展开更多
关键词 TETRAHYDROFURAN Heteropoly compounds Ring opening polymerization Cyclic ether Solid acid
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Effect of Coarse Aggregate Size on and Crack Opening in Normal and Relationship between Stress High Strength Concretes 被引量:4
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作者 Jun ZHANG Qian LIU Lin WANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第5期691-700,共10页
Fine and coarse aggregates play an important role in the fracture of concrete. However, quantitative information available on the effect of the coarse aggregate size on the fracture properties of concrete is still lim... Fine and coarse aggregates play an important role in the fracture of concrete. However, quantitative information available on the effect of the coarse aggregate size on the fracture properties of concrete is still limited. In the present paper, the effect of coarse aggregate size (single grade of 5~10, 10~16, 16~20 and 20~25 mm) on stress-crack opening (σ-w) relation in normal and high strength concretes (compressive strength of 40 and 80 MPa, respectively) was studied. The investigation was based on three-point bending tests implemented by fictitious crack analysis. The result shows that coarse aggregate size and cement matrix strength significantly influence the shape of σ-w curve. For a given total aggregate content, in normal strength concrete, smaller size of aggregate leads to a high tensile strength and a sharp stress drop after the peak stress. The smaller the coarse aggregate, the steeper the σ-w curve. By contrast, in high strength concrete, the effect of aggregate size on σ-w relation almost vanishes. A similar σ-w relation is obtained for the concrete except for the case of 20~25 mm coarse aggregate size. The stress drop after the peak stress is more significant for high strength concrete than that for normal strength concrete. Meanwhile, the smaller the coarse aggregate size, the higher the flexural strength. Fracture energy and characteristic length increase with increasing coarse aggregate size in both normal and high strength concretes. 展开更多
关键词 Aggregate size Stress-crack opening relation Fracture energy Bending test
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Study on the Availability Opening Size of Throttle and Affection to the Velocity Characteristic of Shock Absorber 被引量:3
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作者 周长城 郑志蕴 +1 位作者 顾亮 陈轶杰 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期23-27,共5页
Based on the solution of the governing differential equation for deformation of throttle slice while satisfying required boundary conditions, the coefficient (Gr) and an analytical formula for computing the deformat... Based on the solution of the governing differential equation for deformation of throttle slice while satisfying required boundary conditions, the coefficient (Gr) and an analytical formula for computing the deformation of throttle slice is presented through equivalency transformation, which is a concise, accurate and practical method for throttle slice design and characteristic analysis. Researched the deformation at any radius, compared with ANSYS FEA software by the simulation analysis, the availability opening size of throttle that was defined by the deformation at the valve mouth radius is studied. The affection of valve mouth radius to the damper characteristic is analyzed. Tests are made for the damper characteristic, compared with simulation results, it is shown that Gr method is an accurate computation method for computing the deformation of throttle slice at valve mouth radius, suitihle to use in the damper design, analysis, and verification. The deformation at mouth radius could not be replaced with the outside radius. 展开更多
关键词 DAMPER THROTTLE opening size of throttle velocity characteristic
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Failure behavior around a circular opening in a rock mass with non-persistent joints:A parallel-bond stress corrosion approach 被引量:3
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作者 YANG Xu-xu JING Hong-wen +1 位作者 CHEN Kun-fu YANG Sheng-qi 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2406-2420,共15页
The stability of underground excavations is influenced by discontinuities interspaced in surrounding rock masses as well as the stress condition. In this work, a numerical study was undertaken on the failure behavior ... The stability of underground excavations is influenced by discontinuities interspaced in surrounding rock masses as well as the stress condition. In this work, a numerical study was undertaken on the failure behavior around a circular opening in a rock mass having non-persistent open joints using PFC software package. A parallel-bond stress corrosion(PSC) approach was incorporated to drive the failure of rock mass around the circular opening, such that the whole progressive failure process after excavation was reproduced. Based on the determined micro parameters for intact material and joint segments, the failure process around the circular opening agrees very well with that obtained through laboratory experiment. A subsequent parametric study was then carried out to look into the influence of lateral pressure coefficient, joint dip angle and joint persistency on the failure pattern and crack evolution of the rock mass around the circular opening. Three failure patterns identified are step path failure, planar failure and rotation failure depending on the lateral pressure coefficient. Moreover, the increment of joint dip angle and joint persistency aggravates the rock mass failure around the opening. This study offers guideline on stability estimation of underground excavations. 展开更多
关键词 failure behavior circular opening non-persistent joint PFC software package stress corrosion
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Wave Radiation and Diffraction by A Two-Dimensional Floating Body with An Opening Near A Side Wall 被引量:6
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作者 张洪生 周华伟 《China Ocean Engineering》 SCIE EI CSCD 2013年第4期437-450,共14页
The radiation and diffraction problem of a two-dimensional rectangular body with an opening floating on a semi- infinite fluid domain of finite water depth is analysed based on the linearized velocity potential theory... The radiation and diffraction problem of a two-dimensional rectangular body with an opening floating on a semi- infinite fluid domain of finite water depth is analysed based on the linearized velocity potential theory through an analytical solution procedure. The expressions for potentials are obtained by the method of variation separation, in which the unknown coefficients are determined by the boundary condition and matching requirement on the interface. The effects of the position of the hole and the gap between the body and side wall on hydrodynamic characteristics are investigated. Some resonance is observed like piston motion in a moon pool and sloshing in a closed tank because of the existence of restricted fluid domains. 展开更多
关键词 wave radiation and diffraction floating body with an opening side wall variable separation method domain decomposition
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Regio-and Diasteroselectivity of Rhodium-catalyzed Ring Opening Reaction of Oxabenzonorbornadienes with Heteroatom Nucleophiles 被引量:2
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作者 Ding Qiao YANG He Ping ZENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第7期697-699,共3页
A new rhodium catalyzed ring opening reaction of oxabenzonorbornadienes and its derivatives was described. This reaction forms a new carbon-nitrogen bond via an intermolecular allylic displacement of the bridgehead o... A new rhodium catalyzed ring opening reaction of oxabenzonorbornadienes and its derivatives was described. This reaction forms a new carbon-nitrogen bond via an intermolecular allylic displacement of the bridgehead oxygen with a piperazine's derivatives, which proceeds with very high regioselectivity. 展开更多
关键词 Ring opening RHODIUM-CATALYZED oxabenzonorbornadienes heteroatom nucleophiles.
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Hydrodynamic Characteristics of Square Heaving Plates with Opening Under Forced Oscillation 被引量:1
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作者 CONG Long-fei TENG Bin 《China Ocean Engineering》 SCIE EI CSCD 2019年第6期637-648,共12页
The existence of the heaving plates can improve the heaving motion performance of an offshore structure significantly by providing both extra added mass and damping.In the current research,numerical investigation is c... The existence of the heaving plates can improve the heaving motion performance of an offshore structure significantly by providing both extra added mass and damping.In the current research,numerical investigation is carried out on the hydrodynamic characteristics of both isolated square heaving plate and double square heaving plates with opening by an immersed boundary-lattice Boltzmann method.The effects on hydrodynamic performance of plates due to Keulegan-Carpenter(KC)number,frequency number,opening ratio,opening distribution and spacing of plates are examined.It is found that the heaving plates with optimized opening ratio can provide additional damping compared with the plates without opening.Better hydrodynamic characteristics of double plates can be obtained with the increase of plate spacing. 展开更多
关键词 immersed boundary-lattice Boltzmann method square heaving plate opening shape opening ratio opening distribution plate spacing
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Preparation of a highly efficient Pt/USY catalyst for hydrogenation and selective ring-opening reaction of tetralin 被引量:3
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作者 Qi Wang Zhang-Gui Hou +6 位作者 Bo Zhang Jian Liu Wei-Yu Song De-Sheng Xue Li-Zhi Liu Dong Wang Xin-Guo Chen 《Petroleum Science》 SCIE CAS CSCD 2018年第3期605-612,共8页
Ultrastable Y zeolite(USY)-supported Pt catalyst was prepared by gas-bubbling-assisted membrane reduction. The influence of reaction conditions and the metal and acid sites of catalysts on the catalytic performance ... Ultrastable Y zeolite(USY)-supported Pt catalyst was prepared by gas-bubbling-assisted membrane reduction. The influence of reaction conditions and the metal and acid sites of catalysts on the catalytic performance of catalyst in hydrogenation and selective ring opening of tetralin, 1,2,3,4-tetrahydronaphthalene(THN), was studied. It was found that the optimal reaction conditions were at a temperature of 280 °C, hydrogen pressure of 4 MPa, liquid hourly space velocity of 2 h^-1 and H2/THN ratio of 750. Under these optimal conditions, a high conversion of almost 100% was achieved on the 0.3 Pt/USY catalyst. XRD patterns and TEM images revealed that Pt particles were highly dispersed on the USY, favorable to the hydrogenation reaction of tetralin. Ammonia temperature-programmed desorption and Py-IR results indicated that the introduction of Pt can reduce the acid sites of USY, particularly the strong acid sites of USY. Thus, the hydrocracking reaction can be suppressed. 展开更多
关键词 Hydrogenation and selective ring opening Reaction conditions Supported Pt catalyst TETRALIN
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