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Effect of High Positive Acceleration(+Gz) Environment on Dental Implant Osseointegration:A Preliminary Animal Study

Biomedical and Environmental Sciences 2019年第9期32卷 687-698页

作者： zhu Xiao Ru deng Tian Zheng PANG jian Liang LIU Bing KE Jie Department of Stomatology Air Force Medical Center PLA

Objective To observe the effect of high positive acceleration(+Gz) environment on dental implant osseointegration in a rabbit model and to investigate its *** Forty-eight New Zealand white rabbits were randomly divided into 6 groups. The rabbit’s mandibular incisors were extracted and 1 implant was placed in each socket immediately. After 1 week of rest, the rabbits were exposed to a high +Gz environment, 3 times a week. The rabbits were sacrificed at 3 weeks(2 weeks +Gz exposure), 5 weeks(4 weeks +Gz exposure), and 12 weeks(4 weeks +Gz exposure and 7 weeks normal environment) after surgery, respectively. Specimens were harvested for micro-CT scanning, histological analysis, and real-time polymerase chain reaction *** Compared with those in the control group, the mRNA expression levels of bone morphogenetic protein-2(BMP-2), osteopontin(OPN), and transforming growth factor-β1(TGF-β1)were significantly lower(P < 0.05), while the mRNA expression level of receptor activator of nuclear factor κB ligand(RANKL) and the RANKL/osteoprotegerin(OPG) ratio were significantly higher(P < 0.05)at 3 weeks;values of bone volume fraction, trabecular number, bone-implant contact(BIC), and TGF-β1 and OPG mRNA expression levels were significantly lower(P < 0.05), and the value of trabecular separation, RANKL mRNA expression level and RANKL/OPG ratio were significantly higher(P < 0.05) at 5 weeks;and the value of BIC was still significantly lower(P < 0.05) at 12 weeks in the experimental *** Early exposure to the high +Gz environment after implant surgery might have an adverse effect on osseointegration, and its mechanism could be related to the inhibition of osteoblast activity and promotion of osteoclast activity.

关键词： Positive acceleration Osseointegration Dental implant Micro-CT Real-time polymerase chain reaction Osteoblast

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Effects of frost action on soil physical properties of plough pan

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Chinese Science Bulletin 1999年第5期44卷 445-448页

作者： Ximin deng jian Wang Wenshan zhu Duansheng Chen Liping Liu Chinese Agr Univ Dept Hort Beijing 100094 Peoples R China Chinese Agr Univ Dept Soil & Water Sci Beijing 100094 Peoples R China Chinese Agr Univ Dept Agron Beijing 100094 Peoples R China Chinese Agr Univ Dept Construct Beijing 100094 Peoples R China

Undisturb ed soil cores of loamy clay plough pan were subjected to the treatments of freezing and thawing in laboratory. The effects of frost action on its bulk density, porosity, and hydraulic conductivity were investigated. The results indicate that freezing and thawing significantly reduced the bulk density of plough pan and increased its porosity and hydraulic conductivity. The reduction in the bulk density was closely related to the average daily soil minimum temperature and soil water content.

关键词： plough pan soil physical properties frost action.

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Enhanced Kerr Nonlinearities Caused by Cross Talk Between Optical and Microwave Transitions

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Communications in Theoretical Physics 2008年第10期50卷 961-964页

作者： HU Zheng-Feng deng jian-Liao DU Chun-Guang WANG Yu-zhu The Key Laboratory of Quantum Optics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Science Shanghai 201800 China Department of Physics Tsinghua University Beijing 100084 China

We investigate the enhanced Kerr nonlinearities in four-level atomic vapors driven by a coupling,probe andmicrowave *** the optical one-photon and two-photon resonant conditions,the linear and nonlinear responsesof the weak probe field can be modified by the cross talk among optical and microwave *** enhanced Kerrnonlinearity can form bright optical solitons of the probe field.

关键词： cross-phase modulation Kerr nonlinearity atom-field interaction

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Analysis of hot leg natural circulation under station blackout severe accident

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Nuclear Science and Techniques 2007年第2期18卷 123-128页

作者： deng jian CAO Xuewu School of Nuclear Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

Under severe accidents, natural circulation flows are important to influence the accident progression and result in a pressurized water reactor (PWR). In a station blackout accident with no recovery of steam generator (SG) auxiliary feedwater (TMLB' severe accident scenario), the hot leg countercurrent natural circulation flow is analyzed by using a severe-accident code, to better understand its potential impacts on the creep-rupture timing among the surge line, the hot leg, and SG tubes. The results show that the natural circulation may delay the failure time of the hot leg. The recirculation ratio and the hot mixing factor are also calculated and discussed.

关键词：压水堆全场断电严重事故热管段自然循环

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Photo-induced transformations of Hg(Ⅱ) species in the presence of Nitzschia hantzschiana,ferric ion,and humic acid

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Journal of Environmental Sciences 2010年第1期22卷 76-83页

作者： Lin deng Nansheng deng Liwei Mou Fangtong zhu Department of Municipal Engineering Southeast University Nanjing 210096 China School of Resources and Environmental Science Wuhan University Wuhan 430072 China

Effects of algae Nitzschia hantzschiana, Fe（Ⅲ） ions, humic acid, and pH on the photochemical reduction of Hg（Ⅱ） using the irradiation of metal halide lamps （λ〉 365 nm, 250 W） were investigated. The photoreduction rate of Hg（Ⅱ） was found to increase with increasing concentrations of algae, Fe（Ⅲ） ions, and humic acid. Alteration of pH value affected the photoreduction of Hg（Ⅱ） in aqueous solution with or without algae. The photoreduction rate of Hg（Ⅱ） decreased with increasing initial Hg（Ⅱ） concentration in aqueous solution in the presence of algae. The photochemical kinetics of initial Hg（Ⅱ） and algae concentrations on the photoreduction of Hg（Ⅱ） were studied at pH 7.0. The study on the total Hg mass balance in terms of photochemical process revealed that more than 42% of Hg（Ⅱ） from the algal suspension was reduced to volatile metallic Hg under the conditions investigated.

关键词： photoreduction Nitzschia hantzschiana Hg(Ⅱ) Fe(Ⅲ) humic acid

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汉麻籽多肽靶向抑制胰脂肪酶/胆固醇酯酶的分子作用机制

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食品科学 2025年第2期46卷 38-49页

作者：尹浩朱将雄赵海云钟宇王丹凤邓云上海交通大学农业与生物学院上海200240 上海交通大学云南(大理)研究院云南大理671000 云南省大理白族自治州检验检测院云南大理671000

采用酶活动力学、联合抑制、荧光光谱、等温滴定量热法和分子对接等技术系统探究两种多肽(APAM和RLPA)对胰脂肪酶(pancreatic lipase,PL)和胆固醇酯酶(cholesterol esterase,CE)活性调控效果及分子结合机制。结果表明,RLPA对PL和CE具有... 详细信息

采用酶活动力学、联合抑制、荧光光谱、等温滴定量热法和分子对接等技术系统探究两种多肽(APAM和RLPA)对胰脂肪酶(pancreatic lipase,PL)和胆固醇酯酶(cholesterol esterase,CE)活性调控效果及分子结合机制。结果表明,RLPA对PL和CE具有更强的抑制活性,其半抑制浓度分别为(79.62±3.20)μmol/L和(301.27±14.40)μmol/L。抑制动力学分析表明APAM对两种酶的抑制机制为竞争性抑制,而RLPA则为混合性抑制。联合抑制表明APAM和RLPA在低浓度下均可与奥利司他协同抑制PL和CE,但在高浓度下协同作用减弱,甚至出现拮抗现象。荧光光谱结果表明两种多肽可以通过与PL和CE发生结合产生静态猝灭,改变了酶中脂肪族氨基酸的疏水环境。等温滴定量热法证明多肽与酶的结合过程是自发且放热,主要通过氢键和静电相互作用实现。分子对接模拟进一步分析表明氢键、盐桥和阳离子-π相互作用在多肽与酶的结合中起着至关重要的作用。这项研究丰富了对多肽与PL和CE的相互作用机制的认识,为开发基于汉麻籽蛋白的功能性食品提供了科学依据。

关键词：脂质消化酶抑制机制荧光光谱等温滴定量热法分子模拟

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THREE-DIMENSIONAL FLOW AROUND TWO TANDEM CIRCULAR CYLINDERS WITH VARIOUS SPACING AT Re=220

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Journal of Hydrodynamics 2006年第1期18卷 48-54页

作者： deng jian REN An-lu ZOU jian-feng Department of Mechanics Zhejiang University Hangzhou 310027 China

The flow around two tandem circular cylinders was studied by a three-dimensional numerical simulation of the Navier-Stokes equations at Re=220 . The improved virtual boundary method was applied to model the no-slip boundary condition of the cylinders. The results show that as the spac ing ratio L/D≥4 , the three dimensionality occurs in the wake. When L/D≤3.5 the wake keeps a two-dimensional state at the Reynolds number Re=220 . The critical spacing for the appearance of three-dimensional instability obtained is at the range 3.5〈 L/D 〈 4, similar to the critical spacing found in two-dimensional case. Two sources of instability from upstream and downstream cylinder generate a complicat ed vortex structures in the wake, investigated by streamlines topology analysis in the streamwise plane. Many other interesting problems were also addressed in this paper.

关键词： three-dimensional Navier-Stokes equations,virtual boundary method flow around two tandem circular cylinders three-dimensional vortex structure

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Pressure Analysis of the Initial Process of Diffusion Combustion Surge in a 350 kW Gas Boiler

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Journal of Thermal Science 2022年第2期31卷 582-589页

作者： GAO Han zhu Tong PAN deng School of Mechanical Engineering Tongji UniversityShanghai 201804China

In order to meet the increasingly stringent requirements for nitrogen oxides(NOx)emissions from gas boilers,flue gas recirculation(FGR)technology is commonly used to achieve ultra-low NOx ***,under some ultra-low NOx combustion conditions with FGR,a surge phenomenon occurs in the boiler,which causes a flameout and should be *** this study,the diffusion combustion surge of gas boiler with a rated power of 350 k W and equipped with FGR device was *** characteristic analysis results of the initial process of combustion surge showed that the high-frequency component of pressure is closely related to combustion stability and its change can provide reference for the occurrence of ***,the initial process of surge was analyzed by wavelet packet entropy *** indicated that the wavelet packet entropy of pressure signals could effectively reflect the stability of combustion in the furnace,and it could also be used to study the occurrence of surge.

关键词： diffusion combustion flue gas recirculation wavelet packet entropy surge gas boiler

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Random vortex induced vibration response of suspended flexible cable to fluctuating wind

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Applied Mathematics and Mechanics(English Edition) 2023年第12期44卷 2207-2226页

作者： Genjin MU Weiqiu zhu Maolin deng Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou 310027China

A popular dynamical model for the vortex induced vibration(VIV)of a suspended flexible cable consists of two coupled *** first equation is a partial differential equation governing the cable *** second equation is a wake oscillator that models the lift coefficient acting on the *** incoming wind acting on the cable is usually assumed as the uniform wind with a constant velocity,which makes the VIV model be a deterministic *** the real world,however,the wind velocity is randomly fluctuant and makes the VIV of a suspended flexible cable be treated as a random *** the present paper,the deterministic VIV model of a suspended flexible cable is modified to a random one by introducing the fluctuating *** the normal mode approach,the random VIV system is transformed into an infinite-dimensional modal vibration *** on whether a modal frequency is close to the aeolian frequency or not,the corresponding modal vibration is characterized as a resonant vibration or a non-resonant *** applying the stochastic averaging method of quasi Hamiltonian systems,the response of modal vibrations in the case of resonance or non-resonance can be analytically ***,the random VIV response of the whole cable can be approximately calculated by superimposing the response of the most influential modal *** numerical simulation results confirm the obtained analytical *** is found that the intensity of the resonant modal vibration is much higher than that of the non-resonant modal ***,the analytical results of the resonant modal vibration can be used as a rough estimation for the whole response of a cable.

关键词： vortex induced vibration(VIV) wake oscillator random response suspended flexible cable fluctuating wind

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Recent advances in preparation of metallic superhydrophobic surface by chemical etching and its applications

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Chinese Journal of Chemical Engineering 2023年第9期61卷 221-236页

作者： Shitong zhu Wenyi deng Yaxin Su College of Environmental Science and Engineering Donghua UniversityShanghai 201620China

In the past few decades,inspired by the superhydrophobic surfaces(SHPS)of animals and plants such as lotus leaves,rose petals,legs of water striders,and wings of butterflies,preparing metal materials with metallic SHPS(MSHPS)have attracted great research interest,due to the great prospect in practical *** obtain SHPS on conventional metal materials,it is necessary to construct rough surface,followed by modification with low surface energy *** this paper,the action mechanism and the current research status of MSHPS were reviewed through the following ***,the model of wetting theory was presented,and then the progress in MSHPS preparation through chemical etching method was ***,the applications of MSHPS in self-cleaning,anti-icing,corrosion resistance,drag reduction,oil-water separation,and other aspects were ***,the challenges encountered in the present application of MSHPS were summarized,and the future research interests were discussed.

关键词： Metal Superhydrophobic surface Chemical etching Low adhesion Self-cleaning

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