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You can Lose 6kg By Standing Up at Your Desks
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作者 Carl 《新世纪智能》 2018年第17期73-74,共2页
Office workers could lose almost half a stone a year simply by standing up at their desks, new research suggests.The international study of more than 1,000 men and women found that standing instead of sitting for six ... Office workers could lose almost half a stone a year simply by standing up at their desks, new research suggests.The international study of more than 1,000 men and women found that standing instead of sitting for six hours a day burned an extra 54 calories daily—resulting in significant weight loss. The research, published in the European Journal of Preventive Cardiology. 展开更多
关键词 Lose 6kg standing up
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Standing Up for Life
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作者 JING XIAOLEI 《Beijing Review》 2011年第19期27-27,共1页
A rehabilitation center endeavors to heal the disabled and help them live a normal life Nobody could tell the man who was walking back and forth in the lobby hall of the Deyang Rehabilitation Center for People With D... A rehabilitation center endeavors to heal the disabled and help them live a normal life Nobody could tell the man who was walking back and forth in the lobby hall of the Deyang Rehabilitation Center for People With Disabilities has anything different from normal people, 展开更多
关键词 standing up for Life
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A hybrid tubular standing support for underground mines:Compressive behaviour 被引量:2
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作者 Hongchao Zhao Ting Ren Alex Remennikov 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第2期215-224,共10页
This paper presents the development of an innovative standing support for underground mines.The main feature of this standing support is its exterior container,a combination of polyvinyl chloride(PVC)with large ruptur... This paper presents the development of an innovative standing support for underground mines.The main feature of this standing support is its exterior container,a combination of polyvinyl chloride(PVC)with large rupture strain and fibre-reinforced polymer(FRP)with high strength-to-weight ratio.To demonstrate the advantages of this cementitious grout filled PVC-FRP tubular(PFT)standing support,a series of compression tests were conducted.Test variables included the strength of cementitious grout infill material and the thickness of FRP jacket.Compression tests were also conducted on cementitious grout-filled PVC tubular(PT)support and cementitious grout-filled FRP tubular(FT)support.These tests showed that PFT support presents a typical strain-hardening behaviour together with an outstanding axial deformation ability(>20%of the overall height of the support).In addition,the maximum compressive strength of PFT support is much higher than that of the corresponding PT support and FT support.Furthermore,using thicker FRP jacket or high strength cementitious grout material can enhance the load carrying capacity of PFT support.These comparative results indicated that the high performance of PFT support is mainly attributed to the combination of confining constituents(i.e.PVC and FRP)and infill material. 展开更多
关键词 standing support FRP PVC CONFINEMENT Composite structures Underground mines
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EXISTENCE AND STABILITY OF STANDING WAVES FOR A COUPLED NONLINEAR SCHRDINGER SYSTEM 被引量:1
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作者 曾小雨 张贻民 周焕松 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期45-70,共26页
We study the existence and stability of the standing waves of two coupled SchrSdinger equations with potentials |x|bi(bi ∈ R,i = 1, 2). Under suitable conditions on the growth of the nonlinear terms, we first est... We study the existence and stability of the standing waves of two coupled SchrSdinger equations with potentials |x|bi(bi ∈ R,i = 1, 2). Under suitable conditions on the growth of the nonlinear terms, we first establish the existence of standing waves of the SchrSdinger system by solving a L2-normalized minimization problem, then prove that the set of all minimizers of this minimization problem is stable. Finally, we obtain the least energy solutions by the Nehari method and prove that the orbit sets of these least energy solutions are unstable, which generalizes the results of [11] where b1 = b2 = 2. 展开更多
关键词 nonlinear Schrodinger system constrained variational problem standing waves orbital stubility
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Controllable preparation of vertically standing graphene sheets and their wettability and supercapacitive properties 被引量:2
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作者 周海涛 喻宁 +3 位作者 邹飞 姚朝晖 高歌 申承民 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期169-173,共5页
Vertically standing graphene(VSG) sheets have been fabricated by using plasma enhanced chemical vapor deposition(PECVD) method.The lateral size of VSG nanosheets could be well controlled by varying the substrate t... Vertically standing graphene(VSG) sheets have been fabricated by using plasma enhanced chemical vapor deposition(PECVD) method.The lateral size of VSG nanosheets could be well controlled by varying the substrate temperature.The higher temperature usually gives rise to a smaller sheet size.The wettability of VSG films was tuned between hydrophobicity and hydrophilicity by means of oxygen and hydrogen plasma treatment.The supercapacitor electrode made of VSG sheets exhibited an ideal double-layer-capacitor feature and the specific capacitance reached a value up to 9.62 F·m^(-2). 展开更多
关键词 vertically standing graphene wettability supercapacitor
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Uniaxial compressive behaviour of a FRP standing support made of mine wastes
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作者 Zhenjun Shan Ting Ren +2 位作者 Jan Nemcik Guanzheng Wu Liang Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第8期991-1000,共10页
Twenty-seven specimens were tested to investigate the uniaxial compression behaviour of an innovative standing support for underground space applications.The innovative standing support consisted of an external fibre ... Twenty-seven specimens were tested to investigate the uniaxial compression behaviour of an innovative standing support for underground space applications.The innovative standing support consisted of an external fibre reinforced polymer(FRP)jacket and the infill column made of cementitious grout,tailings and coal wash rejects.Effects of the FRP layers number and water to the cementitious grout(w/g)ratio were evaluated.Test results indicated that lower w/g ratios produced stronger infill columns.With FRP confinement,the standing support demonstrated strain-hardening loading characteristics with a significant improvement in both strength and ductility.The highest strength and strain of the specimens achieved was 58.4 MPa and 11.8%respectively.Compared with the unconfined specimens,the confinement with four FRP layers increased the specimen strength and associated strain up to 3.6 and 27.0 times respectively.A correlation between the compressive strength of the infill material and the ultrasonic pulse velocity was also investigated.Furthermore,a simple design-oriented model was proposed to predict the peak strength and the corresponding strain of the innovative standing support. 展开更多
关键词 standing support Underground spaces FRP Tailings and coal wash rejects Design-oriented model
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Summing-up Speech by NPC Standing Committee Vice-Chairman Zhang Baowen at the Seminar on People-to-People Exchanges between China and Sri Lanka
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作者 Wang Xiaoyi 《International Understanding》 2015年第4期7-9,共3页
Dear Friends,First of all,on behalf of the National People’s Congress and the Chinese Association for International Understanding(CAFIU),I would like to express our thanks to the Sri Lanka friends present here for yo... Dear Friends,First of all,on behalf of the National People’s Congress and the Chinese Association for International Understanding(CAFIU),I would like to express our thanks to the Sri Lanka friends present here for your efforts in promoting China-Sri Lanka friendship.The constant development of China-Sri Lanka relationship embodies the painstaking efforts of all the people concerned. 展开更多
关键词 friends concerned behalf SEMINAR Chairman standing bilateral cooperation THANKS EXCHANGES
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STANDING FIRM IN CHINA'S AUTO INDUSTRY——An Interview with Huang Xiaoping,General Manager of the Yuejin Auto Group Company
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作者 Liu Ningsheng Li Yulong 《China's Foreign Trade》 1996年第7期21-21,共1页
One day in April,our reporters visitedthis national super-large enterprise.Mr Huang Xiaoping,the generalmanager,briefed us on the company’s brilliantpast and bright future. The Yuejin Auto Group Company isfamed all o... One day in April,our reporters visitedthis national super-large enterprise.Mr Huang Xiaoping,the generalmanager,briefed us on the company’s brilliantpast and bright future. The Yuejin Auto Group Company isfamed all over the world for producing YuejinBrand automobiles.In 1958,the firstgeneration of Yuejin Brand automobiles cameout,and China has since had its first 展开更多
关键词 AUTO standing FIRM IN CHINA’S AUTO INDUSTRY An Interview with Huang Xiaoping General Manager of the Yuejin Auto Group Company
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Existence and Stability of Standing Waves with Prescribed L2-Norm for a Class of Schrödinger-Bopp-Podolsky System
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作者 Chunliu Liu 《Journal of Applied Mathematics and Physics》 2022年第7期2245-2267,共23页
In this paper, we look for solutions to the following Schr&#246;dinger-Bopp-Podolsky system with prescribed L<sup>2</sup>-norm constraint , where q ≠ 0, a, &#961;> 0 are constants. At firs... In this paper, we look for solutions to the following Schr&#246;dinger-Bopp-Podolsky system with prescribed L<sup>2</sup>-norm constraint , where q ≠ 0, a, &#961;> 0 are constants. At first, by the classical minimizing argument, we obtain a ground state solution to the above problem for sufficiently small &#961;when . Secondly, in the case p = 6, we show the nonexistence of positive solutions by using a Liouville-type result. Finally, we argue by contradiction to investigate the orbital stability of standing waves for . 展开更多
关键词 Schrödinger-Bopp-Podolsky System standing Waves Normalized Solution Orbital Stability
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Study on Free-Standing Riser Under Different Working Conditions Based on 3D Co-Rotational Beam Element
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作者 HUANG Chen GU Ji-jun +3 位作者 JIA Ji-chuan CHEN Lei-lei WANG Shu-jiang GAO Lei 《China Ocean Engineering》 SCIE EI CSCD 2024年第5期725-738,共14页
When the free standing riser(FSR)is in service in the ocean,its mechanical properties are affected by various factors,including complex ocean current forces,buoyancy of the buoyancy can,and torque caused by the deflec... When the free standing riser(FSR)is in service in the ocean,its mechanical properties are affected by various factors,including complex ocean current forces,buoyancy of the buoyancy can,and torque caused by the deflection of the upper floating body.These loads have a great influence on the deformation and internal force of the FSR.The static performance of FSR is investigated in this research under various working conditions.The finite element model of FSR is established based on the co-rotational method.The arc length approach is used to solve the model.The load is exerted in increments.The current load on the riser changes with the configuration of the riser.The accuracy of the numerical method is verified by Abaqus software.The calculation time is also compared.Then,the effects of uniform current,actual current and floating body yaw motion on FSR are studied by parameter analysis.Additionally,the influence of the FSR on the ocean current after the failure of part of the buoyancy can chamber is analyzed.The results show that the numerical model based on the co-rotational method can effectively simulate the large rotation and torsion behavior of FSR.This method has high computational efficiency and precision,and this method can quickly improve the efficiency of numerical calculation of static analysis of deep-water riser.The proposed technology may serve as an alternative to the existing proprietary commercial software,which uses a complex graphical user interface. 展开更多
关键词 free standing riser(FSR) co-rotational method finite element method ocean current nonlinear analysis TORSION
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Assessing cutter-rock interaction during TBM tunnelling in granite:Large-scale standing rotary cutting tests and 3D DEM simulations
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作者 Xin Huang Miaoyuan Tang +4 位作者 Shuaifeng Wang Yixin Zhai Qianwei Zhuang Chi Zhang Qinghua Lei 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3595-3615,共21页
The widespread utilisation of tunnel boring machines(TBMs)in underground construction engineering requires a detailed investigation of the cutter-rock interaction.In this paper,we conduct a series of largescale standi... The widespread utilisation of tunnel boring machines(TBMs)in underground construction engineering requires a detailed investigation of the cutter-rock interaction.In this paper,we conduct a series of largescale standing rotary cutting tests on granite in conjunction with high-fidelity numerical simulations based on a particle-type discrete element method(DEM)to explore the effects of key cutting parameters on the TBM cutter performance and the distribution of cutter-rock contact stresses.The assessment results of cutter performance obtained from the cutting tests and numerical simulations reveal similar dependencies on the key cutting parameters.More specifically,the normal and rolling forces exhibit a positive correlation with penetration but are slightly influenced by the cutting radius.In contrast,the side force decreases as the cutting radius increases.Additionally,the side force shows a positive relationship with the penetration for smaller cutting radii but tends to become negative as the cutting radius increases.The cutter's relative effectiveness in rock breaking is significantly impacted by the penetration but shows little dependency on the cutting radius.Consequently,an optimal penetration is identified,leading to a low boreability index and specific energy.A combined Hertz-Weibull function is developed to fit the cutter-rock contact stress distribution obtained in DEM simulations,whereby an improved CSM(Colorado School of Mines)model is proposed by replacing the original monotonic cutting force distribution with this combined Hertz-Weibull model.The proposed model outperforms the original CSM model as demonstrated by a comparison of the estimated cutting forces with those from the tests/simulations.The findings from this work that advance our understanding of TBM cutter performance have important implications for improving the efficiency and reliability of TBM tunnelling in granite. 展开更多
关键词 Large-scale standing rotary cutting test Discrete element method(DEM)simulation Cutter-rock interaction Improved CSM(Colorado School of Mines) model Cutting force
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Fabrication of Free Standing Nanocellulose Film via Spray Coating and its Biomedical Application: A Review
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作者 Kirubanandan Shanmugam 《Journal of Clinical and Nursing Research》 2024年第4期411-447,共37页
Spraying nanocellulose onto films provides a quick and scalable way to create free-standing films with exceptional consistency and customizable thickness. This method increases the application of nanocellulose films i... Spraying nanocellulose onto films provides a quick and scalable way to create free-standing films with exceptional consistency and customizable thickness. This method increases the application of nanocellulose films in various industries and satisfies the requirements of large-scale production. In the field of biomedicine, spray-coated free-standing nanocellulose films hold great promise for applications such as drug delivery, tissue engineering, wound healing, device coatings, and biosensing. They are excellent nanomaterials for a variety of biomedical applications due to their special qualities, including biocompatibility, high mechanical strength, porous structure, large surface area, and adaptability. This paper reviewed the detailed exposure of the spray coating process of nanocellulose suspension onto free- standing films and its biomedical applications. 展开更多
关键词 SPRAYING Nanocellulose Film Free standing Film Thickness Basis weight
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Effects of Standing Time during Pretreatment on the Nitrite Concentration Detected by Spectrophotometric Method
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作者 Yingfei Zeng Juan Hu +2 位作者 Xianglong Bian Qianfeng Xia Tingwei Hu 《Journal of Materials Science and Chemical Engineering》 2024年第2期73-83,共11页
Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a... Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a great influence on the concentration of nitrite tested by spectrophotometric method. In this context, three kinds of food samples are prepared, including canned mustard, canned fish and home-made pickled water. A series of standing times are placed during the sample pretreatments and the corresponding nitrite contents in these samples are detected by spectrophotometric method based on N-ethylenediamine dihydrochloride. This study aims to find out a reasonable standing time during the pretreatment of food sample, providing influence factor for precise detection of nitrite. 展开更多
关键词 standing Time Spectrophotometric Method Nitrite Detection
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Existence and Stability of Standing Waves for the Nonlinear Schrödinger Equation with Combined Nonlinearities and a Partial Harmonic Potential
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作者 Wei Wang 《Journal of Applied Mathematics and Physics》 2024年第5期1606-1615,共10页
In this paper, we study the existence of standing waves for the nonlinear Schrödinger equation with combined power-type nonlinearities and a partial harmonic potential. In the L<sup>2</sup>-supercriti... In this paper, we study the existence of standing waves for the nonlinear Schrödinger equation with combined power-type nonlinearities and a partial harmonic potential. In the L<sup>2</sup>-supercritical case, we obtain the existence and stability of standing waves. Our results are complements to the results of Carles and Il’yasov’s artical, where orbital stability of standing waves have been studied for the 2D Schrödinger equation with combined nonlinearities and harmonic potential. 展开更多
关键词 Nonlinear Schrödinger Equation Orbital Stability standing Waves
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Study on the Variation in Growth Traits of Cupressus funebris
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作者 谭小梅 周益权 《Agricultural Science & Technology》 CAS 2015年第3期558-561,共4页
[Objective] This study aimed to investigate the variation in growth traits of Cupressus funebris in Chongqing Municipality, thus laying the foundation for further breeding and improvement of fine varieties. [Method] G... [Objective] This study aimed to investigate the variation in growth traits of Cupressus funebris in Chongqing Municipality, thus laying the foundation for further breeding and improvement of fine varieties. [Method] Growth traits of three fine stands of C. funebris in Qijiang, Pengshui and Youyang of Chongqing Municipality were investigated. [Result] The results showed that C. funebris stand in Pengshui exhibited the best growth performance, followed by C. funebris stand in Qijiang; C. funebris stand in Youyang exhibited the poorest growth performance. The average volume growth of C. funebris in Pengshui, Qijiang and Youyang was 0.14, 0.11 and 0.06 m^3, respectively. Among different stands, variation coefficients of major growth traits were above 11.31%, and the maximum variation coefficient of the volume was 39.11%; within the stands, variation coefficients of plant height were basically the same (about 20%). The variation coefficient of diameter at breast height in Qijiang reached the maximum of 42.42%, followed by that in Youyang. The variation coeffi- cients of volume and diameter at breast height were consistent; seed bearing coefficient (SBC) of C. funebris stand in Pengshui exhibited the maximum variation, which indicated that C. funebris stand in Pengshui was conducive to establishing seed stands and constructing seed orchard by using the selected stands. [Conclusion] It is necessary to conduct provenance selection. 展开更多
关键词 Cupressus funebris Growth traits VARIATION PROVENANCE STAND
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Stand structure and height-diameter relationship of a degraded Populus euphratica forest in the lower reaches of the Tarim River, Northwest China 被引量:12
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作者 AISHAN Tayierjiang HALIK ümüt +3 位作者 Florian BETZ TIYIP Tashpolat DING Jianli NUERMAIMAITI Yiliyasijiang 《Journal of Arid Land》 SCIE CSCD 2015年第4期544-554,共11页
Understanding stand structure and height-diameter relationship of trees provides very useful information to establish appropriate countermeasures for sustainable management of endangered forests. Populus euphratica, a... Understanding stand structure and height-diameter relationship of trees provides very useful information to establish appropriate countermeasures for sustainable management of endangered forests. Populus euphratica, a dominant tree species along the Tarim River watershed, plays an irreplaceable role in the sustainable development of regional ecology, economy and society. However, as the result of climate changes and human activities, the natural riparian ecosystems within the whole river basin were degraded enormously, particularly in the lower reaches of the river where about 320 km of the riparian forests were either highly degraded or dead. In this study, we presented one of the main criteria for the assessment of vitality of P. euphrafica forests by estimating the defoliation level, and analyzed forest structure and determined the height-diameter (height means the height of a tree and diameter means the diameter at breast height (DBH) of a tree) relationship of trees in different vitality classes (i.e. healthy, good, medium, senesced, dying, dead and fallen). Trees classified as healthy and good ac- counted for approximately 40% of all sample trees, while slightly and highly degraded trees took up nearly 60% of total sample trees. The values of TH (tree height) and DBH ranged from 0-19 m and 0-125 cm, respectively. Trees more than 15 m in TH and 60 cm in DBH appeared sporadically. Trees in different vitality classes had different distribution patterns. Healthy trees were mainly composed more of relatively younger trees than of degraded tress. The height-diameter relationships differed greatly among tress in different vitality classes, with the coefficients ranging from 0.1653 to 0.6942. Correlation coefficients of TH and DBH in healthy and good trees were higher than those in trees of other vitality classes. The correlation between TH and DBH decreased with the decline of tree vitality. Our results suggested that it might be able to differentiate degraded P. euphratica trees from healthy trees by determining the height-diameter correlation coefficient, and the coefficient would be a new parameter for detecting degradation and assessing sustainable management of floodplain forests in arid regions. In addition, tree vitality should be taken into account to make an accurate height-diameter model for tree height prediction. 展开更多
关键词 stand structure height-diameter relationship Populus euphratica tree vitality Tarim River
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Contact Analysis and Modeling of Standing Wave Linear Ultrasonic Motor 被引量:6
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作者 时运来 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第6期1235-1242,共8页
A contact model for describing the contact mechanics between the stator and slider of the standing wave linear ultrasonic motor was presented. The proposed model starts from the assumption that the vibration character... A contact model for describing the contact mechanics between the stator and slider of the standing wave linear ultrasonic motor was presented. The proposed model starts from the assumption that the vibration characteristics of the stator is not affected by the contact process. A modified friction models was used to analyze the contact problems. Firstly, the dynamic normal contact force, interface friction force, and steady-state characteristics were analyzed. Secondly, the influences of the contact layer material, the dynamic characteristics of the stator, and the pre-load on motor performance were simulated. Finally, to validate the contact model, a linear ultrasonic motor based on in-plane modes was used as an example. The corresponding results show that a set of simulation of motor performances based on the proposed contact mechanism is in good agreement with experimental results. This model is helpful to understanding the operation principle of the standing wave linear motor and thus contributes to the design of these types of motor. 展开更多
关键词 standing wave linear ultrasonic motor intermittent contact contact model
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Temporal Variation in Sap-Flux-Scaled Transpiration and Cooling Effect of a Subtropical Schima superba Plantation in the Urban Area of Guangzhou 被引量:6
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作者 ZHU Li-wei ZHAO Ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1350-1356,共7页
Agriculture could suffer the water stress induced by climate change. Because climate warming affects global hydrological cycles, it is vital to explore the effect of tree transpiration, as an important component of te... Agriculture could suffer the water stress induced by climate change. Because climate warming affects global hydrological cycles, it is vital to explore the effect of tree transpiration, as an important component of terrestrial evapotranspiration, on the environment. Thermal dissipation probes were used to measure xylem sap flux density of a Schima superba plantation in the urban area of Guangzhou City, South China. Stand transpiration was calculated by mean sap flux density times total sapwood area. The occurrence of the maximum sap flux density on the daily scale was later in wet season than in dry season. The peak of daily sap flux density was the highest of 59 g m-2 s^-1 in July and August, and the lowest of 28 g m-2 s-1 in December. In the two periods (November 2007-October 2008 and November 2008-October 2009), the stand transpiration reached 263.2 and 291.6 ram, respectively. During our study period, stand transpiration in wet season (from April to September) could account for about 58.5 and 53.8% of the annual transpiration, respectively. Heat energy absorbed by tree transpiration averaged 1.4×10s and 1.6×10s kJ per month in this Schima superba plantation with the area of 2 885 m2, and temperature was reduced by 4.3 and 4.7℃ s^-1 per 10 m3 air. 展开更多
关键词 Schima superba plantation sap flux density stand transpiration cooling effect
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Quantification of ventilation enhancement using the Eye CAN roof support 被引量:3
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作者 Shook Michael T Sindelar Mark F, +1 位作者 Jiang Hua Luo Yi 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第1期153-158,共6页
Convergence of roof and floor in underground mine openings is a common occurrence. This convergence not only adversely affects the ability of workers, equipment and supplies to travel through the mine, it also reduces... Convergence of roof and floor in underground mine openings is a common occurrence. This convergence not only adversely affects the ability of workers, equipment and supplies to travel through the mine, it also reduces the effectiveness of the mine ventilation system, which is essential for the dilution of methane gas and airborne respirable dust. While installing secondary standing supports to control floor and roof convergence, such supports, by nature, partially obstruct a portion of the airway. These added obstructions inhibit the ability of the ventilation system to operate as efficiently as it could by increasing the resistance in and reducing the cross-sectional area of the airway. This study introduces and demonstrates the benefits of The Eye CAN^(TM) standing roof support, which controls floor and roof convergence and is less obstructive to air flow than conventional wooden cribs. Laboratory findings show that the normal resistance of a supported lined airway is reduced by using this new product from Burrell Mining Products, Inc., while providing the same roof support characteristics of an established product—The CANò. Load vs. displacement curves generated from laboratory tests demonstrated that this new product behaves with the same roof support characteristics as others in The CAN product family. Ventilation data gathered from a simulated mine entry was then used for computational fluid dynamics(CFD) modeling.The CFD analysis showed an improvement with The Eye CAN vs. other accepted forms of standing roof support. This proof-of-concept study suggests that, when using this new product made by Burrell Mining Products, Inc., not only will the convergence from the roof and floor be controlled, but airway resistance will also be reduced. 展开更多
关键词 standing roof support CAN Ventilation LOAD-DISPLACEMENT Eye CAN
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Numerical simulation of standing waves for ultrasonic purification of magnesium alloy melt 被引量:3
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作者 邵志文 乐启炽 +1 位作者 崔建忠 张志强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期382-387,共6页
It was attempted to enhance and accelerate the separation of oxidation inclusions from magnesium alloy melt by virtue of ultrasonic agglomeration technology.In order to investigate the feasibility and effectiveness of... It was attempted to enhance and accelerate the separation of oxidation inclusions from magnesium alloy melt by virtue of ultrasonic agglomeration technology.In order to investigate the feasibility and effectiveness of standing waves for ultrasonic purification of magnesium alloy melt,numerical simulation and relevant experiment were carried out.The numerical simulation was broken into two main aspects.On one hand,the ultrasonic field propagations within the cells with various shapes were characterized by numerical solutions of the wave equation and with a careful choice of geometry a nearly idealized standing wave field was finally obtained.On the other hand,within such a standing wave field the agglomeration behavior of oxidation inclusions in magnesium alloy melt was analyzed and discussed.The agglomeration time and agglomeration position of oxidation inclusions were predicted with numerical simulation method.The results show that the oxidation inclusions whose apparent densities are close to the density of the melt can agglomerate at wave nodes in a short time which to a great extent enhances and accelerates the separation of oxidation inclusions from magnesium alloy melt. 展开更多
关键词 magnesium alloy melt PURIFICATION standing waves numerical simulation
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