999 resultados para capability mechanism


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A hydrodynamic-thermodynamic equation set was set up to reflect the formational mechanism and evolution of the Northern Yellow (Huanghai) Sea cold water mass (NYSCWM) and its density circulation. Appropriate mathematical physical models were established by using some physical postulations. An approximate analytic solution to expound the distributions of temperature and three-dimensional current velocity, which can be used to expound the formational mechanism of the NYSCWM and its density circulation is obtained by using the theory of boundary layer and perturbational analyses.

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The theoretical solution of the model of the Northern Yellow (Huanghai) Sea Cold Water Mass (NYSCWM) reveals that the NYSCWM is mainly formed through the continuous temperature increase of the overwintered water body above the Northern Yellow Sea Depression (NYSD) after spring when heat is continuously conducted from the sea surface to the deeper layer. In the NYSCWM's growing period, (June-July), nonlinear vertical convection and advection effects continuously increase, and are gradually balanced by the heat diffusion effect as the temperature increases from the surface to the bottom, which leads to the formation of an intensive thermocline and lateral front. Meanwhile, the three-dimensional circulation correspondingly occurs. In the NYSCWM's entire growing period, the horizontal circulation is always in the cyclonic motion, while the vertical circulation passes through a transition from a period with the cold centre as downwelling to a period with the cold centre as upwelling.

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The inhibitory effect of 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) and 2,4,6-tri(2-pyridyl)-s-triazine (TPT) molecules on the corrosion of mild steel in 1 mol/L HCl and microcosmic inhibitory mechanism were investigated by X-ray photoelectron spectroscopy and ellipsometry. XPS results showed that C Is and N Is peaks of TTC, C Is and N Is peaks of TPT and their integral areas were obtained, which suggested the layer of the inhibitors (TTC or TPT) should have effectively protected the mild steel surface from the corrosion; and the depression from the inhibitors for the corrosion of mild steel surface was studied using ellipsometry combined with potentiodynamic polarization and the phasic difference was gained, which displayed the inhibitory coverage of the inhibitors formed.

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The inhibiting effect and mechanism of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylicacid(ciprofloxacin), 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid (norfloxacin) and (-)-(S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7 H-pyrido(1,2,3-de)-1,4-benzoxazine-6 carboxylic acid (ofloxacin) on the corrosion of mild steel in 1 mol/L HCl have been studied using electrochemical method, quantum chemical method and SEM at 303 K. The potentiodynamic results showed that these compounds suppressed both cathodic and anodic processes of mild steel corrosion in 1 mol/L HCl. The impedance spectroscopy showed that R-p values increased, and C-dl values decreased with the rising of the working concentration. Quantum chemical calculation showed that there was a positive correlation between some inhibitors structure properties and the inhibitory efficiency. The inhibitors function through adsorption followed Langmuir isotherm, and chemisorption made more contribution to the adsorption of the inhibitors on the steel surface compared with physical adsorption. SEM analysis suggested that the metal had been protected from aggressive corrosion because of the addition of the inhibitors.

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The paper systematically discusses the mechanism for glycinebetaine to improve plant salt resistance and its research advances in genetic engineering at home and abroad as well as summarizing the research progresses about the key enzymes and their genetic engineering in glycinebetaine biosynthesis. It suggests that on the basis of further understanding the mechanism for glycinebetaine to improve plant salt resistance,the transformation of the genes relating to glycinebetaine biosynthesis should be carried out in major crops so that new plant varieties resistant to salt can be obtained.

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To explore the reactivities of alkene (-CH=CH2) and carboxy (-COOH) group with H-Si under UV irradiation, the addition mechanism for the reactions of SiH3 radical with propylene and acetic acid was studied by using the B3LYP/6-311++ G(d,p) method. Based on the surface energy profiles, the dominant reaction pathways can be established; i.e., SiH3 adds to the terminal carbon atom of the alkene (-CH=CH2) to form an anti-Markovnikov addition product, or adds to the oxygen atom of the carboxy group (-COOH) to form silyl acetate (CH3-COOSiH3). Because the barrier in the reaction of the carboxy group (39.9 kJ/ mol) is much larger than that of alkene (11.97 kJ/mol), we conclude that the reaction of bifunctional molecules (e.g., omega-alkenoic acid) with H-Si under irradiation condition is highly selective; i.e., the alkene group (-CH= CH2) reacts with SiH3 substantially faster than the carboxyl group (-COOH), which agrees well with the experimental results. This provides the possibility of preparing carboxy-terminated monolayers on silicon surface from omega-alkenoic acids via direct photochemical reaction.

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提出并研制一种基于自适应移动机构的管内探查机器人。通过对机器人传动机构的设计,实现了在不增加驱动电动机数量的前提下,机器人具有适应不同管道直径的能力。机器人的传动机构能够在管道直径改变时,自动地改变行走部件的输出形式以克服障碍,完成越障任务。在没有应用链式多节构型的情况下,机器人配备一个驱动电动机就能够完成越障任务,改善了传统螺旋驱动式机器人越障能力不高的问题,同时也提高了对驱动电动机的使用效率。为了分析试验中发现的机器人保持架自转现象,对机器人进行运动分析,并由分析结果对相关部分进行改进。试验结果表明,该机器人能够在内径为190 mm和180 mm的管道中行进,并能够顺利通过两节管道间形成的同心台阶障碍,验证了自适应移动机构的行走能力。

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蛇形机器人具有比传统移动机器人更强的运动能力,为实现机器人的三维运动而开发的蛇形机器人巡视者II是一个具有强驱动力和高机动性的三维蛇形机器人。它由具有3自由度的模块化单元组成,该单元具有俯仰、偏航和回转3自由度,单元的俯仰和偏航运动是通过由3个伞齿轮组成的差速机构耦合驱动。该单元的圆柱形外壳周围安装有一系列的被动轮来增加机器人运动灵活性。对蛇形机器人模块单元的自由度作了详细分析,并基于机器人的运动机动性设计三维蛇形机器人的单元结构。给出蛇形机器人的控制系统结构,并对耦合变量进行解耦。将蛇形机器人的蜿蜒运动和扭转运动两种基本步伐应用到巡视者II上,试验结果证明了该三维蛇形机器人具有很强的机动性和运动能力。

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针对多机器人探索未知环境问题,提出了改进型边界探索算法。该算法综合考虑边界角度和距离两种因素,引入分散机制,使机器人团队协同工作,避免出现拥挤,减少探索过程中的重复覆盖和路径交叉现象。基于与其他方法的实验比较结果表明,该探索方法使多机器人具有更好的团队协作能力,提高了探索效率。

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轮腿复合移动机器人具有很好的地面适应能力和越障能力。本文通过对机器人系统结构的分析和其越障高度的静态分析,计算出机器人能够越障的最大高度,并提出了针对典型地形环境(沟、坎、台)越障问题的机器人构型优化以及轮腿运动协调控制算法,而且通过实验验证了算法的有效性。

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冗余度机构具有高度的灵活性和避障能力,利用冗余自由度可以改善仿人机器人手臂的运动性能。以实现人体手臂的运动特性和操作灵活性为目标,研制了一种7DOF冗余仿人机器人手臂,根据冗余手臂的机构学特点,研究了手臂的运动学和动力学性能,并在工作空间、肘部关节的自运动能力以及手臂自重引起的关节重力矩等方面与其它两种典型的冗余手臂构形进行了比较分析。

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The lithology of the buried hill of Triassic Budate group in Beier depression is epimetamorphic clastic rock and volcanic clastic rock stratum. Recently the favorable hydrocarbon show was discovered in buried hill of base rock, and large-duty industrial oil stream was obtained in some wells in Beier depression. Based on the information of seismos and wells, the tectonic framework, tectonic deformation times and faulted system of the Beier depression are comprehensively studied, then configuration, evolutional history, genetic type and distributed regularity of buried hill are defined. According to observing description and analysis of core sample, well logging and interpretive result of FMI, the lithological component, diagenetic type and diagenetic sequence of buried hill reservoir are confirmed, then reservoir space system of buried hill is distinguished, and vegetal feature, genetic mechanism and distributed regularity of buried hill fissure are researched, at the same time the quantitative relationship is build up between core fissures and fissures interpreted by FMI. After that fundamental supervisory action of fault is defined to the vegetal degree of fissure, and the fissure beneficial places are forecasted using fractal theory and approach. At last the beneficial areas of Budate group reservoir are forecasted by reservoir appraisal parameters optimization such as multivariate gradually regression analysis et. al. and reservoir comprehensive appraisal method such as weighing analyze and clustering procedure et. al. which can provide foundation for the next exploratory disposition. Such production and knowledge are obtained in this text as those: 1. Four structural layers and two faulting systems are developed, and four structural layers are carved up by three bed succession boundary surfaces which creates three tectonic distortional times homology. Three types of buried hill are divided, they are ancient physiognomy buried hill, epigenetic buried hill, and contemporaneous buried hill. 2. Reservoir space of Budate buried hill is mainly secondary pore space and fissure, which distributes near the unconformity and/or inside buried hill in sections. The buried hill reservoir experienced multi-type and multi-stage diagenetic reconstruction, which led to the original porosity disappeared, and multi secondary porosity was created by dissolution, superficial clastation and cataclasis et. al. in diagenetic stage, which including middle crystal pore, inter crystal pore, moldic pore, inter particle emposieu, corrosion pore space and fissure et. al. which improved distinctly reservoir capability of buried hill. 3. The inner reservoir of buried hill in Beier depression is not stratigraphic bedded construction, but is fissure developing place formed by inner fault and broken lithogenetic belt. The fissures in inner reservoir of buried hill are developed unequally with many fissure types, which mainly are high angle fissure and dictyonal fissures and its developing degree and distribution is chiefly controlled by faulting. 4. The results of reservoir comprehensive evaluate and reservoir predicting indicates that advantageous areas of reservoir of buried hill chiefly distributes in Sudeerte, Beixi and Huoduomoer, which comprehensive evaluate mainly Ⅱand Ⅲ type reservoir. The clues and results of this text have directive significance for understanding the hydrocarbon reservoir condition of buried hill in Beier depression, for studying hydrocarbon accumulated mechanism and distributed regularity, and for guiding oil and gas exploration. The results of this text also can enrich and improve nonmarine hydrocarbon accumulated theory.

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The sediment and diagenesis process of reservoir are the key controlling factors for the formation and distribution of hydrocarbon reservoir. For quite a long time, most of the research on sediment-diagenesis facise is mainly focusing on qualitative analysis. With the further development on exploration of oil field, the qualitative analysis alone can’t meet the requirements of complicated requirements of oil and gas exploreation, so the quantitative analysis of sediment-diagenesis facise and related facies modling have become more and more important. On the basis of the research result from stratum and sediment on GuLong Area Putaohua Oil Layer Group, from the basic principles of sedimentology, and with the support from the research result from field core and mining research results, the thesis mainly makes the research on the sediment types, the space framework of sands and the evolution rules of diagenesis while mainly sticking to the research on sediment systement analysis and diagenetic deformation, and make further quantitative classification on sediment-diageneses facies qualitatively, discussed the new way to divide the sediment-diagenesis facies, and offer new basis for reservoir exploration by the research. Through using statistics theory including factor analysis, cluster analysis and discriminant analysis, the thesis devided sediment-diagenesis facies quantitatively. This research method is innovative on studying sediment-diagenesis facies. Firstly, the factor analysis could study the main mechanism of those correlative variables in geologic body, and then could draw a conclusion on the control factors of fluid and capability of reservoir in the layer of studying area. Secondly, with the selected main parameter for the cluster analysis, the classification of diagenesis is mainly based on the data analysis, thus the subjective judgement from the investigator could be eliminated, besides the results could be more quantitative, which is helpful to the correlative statistical analysis, so one could get further study on the quantitative relations of each sediment-diagenesis facies type. Finally, with the reliablities of discriminant analysis cluster results, and the adoption of discriminant probability to formulate the chart, the thesis could reflect chorisogram of sediment-diagenesis facies for planar analysis, which leads to a more dependable analytic results.According to the research, with the multi-statistics analysis methods combinations, we could get quantitative analysis on sediment-diagenesis facies of reservoir, and the final result could be more reliable and also have better operability.

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Because of the high resolution, stalagmite laminae can play an important role in the paleoclimate reconstructions. However, few investigations for the formation mechanisms of stalagmite lamilae have been done. Based on two-year observation on calcite growth rate at the drip sites, three-year monitoring of hydrodynamics, physics and chemistry of drip waters at different drip sites and the surrounding environments inside and outside the Beijing Shihua Cave, the seasonal variations of calcite growth rate are revealed and the results can be concluded as follows: 1. The drip waters inside the Cave are mostly sourced from the summer rain, and its minimal response-time to the atmospheric precipitation is less than one day. There are three types of response relationships between the precipitation and the drip rate variations: rapid response type, time-lag response type and stable response type. For rapid response type, the drip discharge is recharged through the flow routes along intensive fractures and interconnectivities; for time-lag response type, the drip discharge is recharged by double-porosity system composed of a high conductivity, low storage capability conduit network and a low-conductivity high-storage capability rock matrix under variable boundary conditions; for stable response type, the drip discharge is mainly recharged by seepage flow and base flow. 2. The observation shows that, inside the Cave, the growth rate of calcite is generally lower in rainy seasons and higher in dry seasons. During the rainy seasons, the drip water is characterized by a lower pH value, higher [Ca2+], [Mg2+], [SO42-] and electrical conductivity (EC) values. According to the calculations of saturation index of calcite (SIc), pCO2 of the drip water, as well as the synthetical analysis of other possible factors, the calcite growth rate is found to be principally influenced by the drip water saturation index of calcite (SIc). And the drip rate and pCO2 in the drip water and in the cave air play the secondly important roles in this process. The recharge mode of heavy rainfall events in the rainy seasons should probably be the main driving force that controls the physicochemical properties and calcite sediment of the drip waters. The abrupt decrease of sedimentary rate and the sharp peak of DOC in drip water in the rainy season probably forms the thin opaque (luminescent under ultraviolet radiation) layers observed in the stalagmites, whereas the relatively higher sedimentary rate in the dry seasons may be responsible for the thicker bright layers. The investigation elucidated here preliminarily reveals the formation mechanism of the stalagmite laminae in Beijing Shihua Cave.

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This paper builds the model of oil accumulation and achieves the prediction of exploration goal. It uses multiple subject means, the ways of synthetic research and the viewpoint of analyzing genesis, with the academic guidance of sedimentology, structural geology, petroleum geology and geochemistry, the basis of strata sequence frame and structural frame, the frame of "four history" - the burying history, the structural history, the filling history and the evolving history of oil, the masterstroke of hydrocarbon's generation, migration and accumulation, the aim of revealing the genetic relation between mature source rock and oil reservoir in space and time. Some achievements and viewpoints in this study are following. 1. It is proposed that the structural evolution in this area had many periods, and the structural movement of the Xiazijie group telophase formed the structural pattern for the first time. 2. The character of strata sequence in this area is divided by the character of episodic cycle firstly. The study of dividing the facies of single well and the facies of well tie is based on the data of single well. The character of sedimentary facies is con-structed initially. 3. It is believed that Jiamuhe group is the main source rock, which can supply considerable oil and gas resources for the first time. Some criterions of source rock such as the type ,the abundance in Jiamuhe group are analysed. Using the thermal history of source rock, we drawn a conclusion that the original type of source rock in Jiamuhe group is II_1-III, and the abundance achived the level of good source rock, and this set of source rock had contributed to this area. 4. The reservoir strata in this area are assessed and analysed with the reservoir evaluation. There are multi-type reservoirs, such as volcanic lava facies, sedimentary clast facies, continental belch facies. The physical property in reservoir strata is characterized by low porosity and low permeability. The study of diagenetic stage show that the diageneses in Jiamuhe group is A-Bsubage, and the reservoir room is mainly secondary corroded hollow and cleft. 5. The synthetic research on oil system in Jiamuhe group is made for the first time. The type of petroleum system is divided , and we consider that the petroleum system of Jiamuhe group is at the reliable rank. There are two critical time in oil accumulation through studying the critical time of oil accumulation : the early generation of hydrocarbon is oil, and the later is gas. 6. The mechanism of accumulation is analysed. We consider that the accu-mulation of oil in this area has many periods, and the early generated hydrocarbon is expeled by the later , and formed the character of zonal distribution in planar. 7. A bran-new model of oil and gas is proposed. Beneficial enrichment area of oil and gas is analyzed, which can be divided into three sections: Section I can be divided into two sections: I_1 and I_2. The lower subgroup of Jiamuhe is covered by the triassic layer of I_1 section. Fault zone and near the foot wall of fault are charactered with thick phase belt. Then the cover capability in this area is relatively poor, oil can migrate into triassic layer by vertical or lateral migration , and forms I_1 Kelamayi triassic oil pool consequently. The lower subgroup of Jiamuhe is covered by the triassic layer of I_2 section ,which is charactered with thin phase belt. Then the cover capability in this area is relatively good, and forms I_1 Kelamayi triassic oil pool consequently. Section II can be divided into two sections: II_1-I_(I~2). The cover of Jiamuhe group in section II_1 is the low resistivity segment in Wuerhe group, which has thin lithology and poor porosity and permeability. Oil and gas in Jiamuhe group can be covered to form beneficial accumulation area. There are some wells in this area, such as Ke 007 well, 561 well. The thick phase belt layer of Wuerhe high resistivity segment in section II_2 has unconformable relation with Jiamuhe group. The cover ability of the high resistivity segment is poor, petroleum in Jiamuhe can migrate into Wuerhe layer vertically. This area is the beneficial area for accumulating petroleum in Wuerhe layer. there are some wells in this area, such as Ke 75 well, Ke 76 well, Ke 77 well, Ke 78 well, Ke 79 well. Section III can also be divided into two sections: III_1 and III_2. Wuerhe group in section III_1 has unconformable relation with Jiamuhe group. There is thick lithology and poor cover in Wuerhe group, but the strata sequence evolution character of upper subgroup in Jiamuhe group has determined that it has lateral and vertical cover ability. thus, this area is petroleum abundant belt of jiamuhe group, which has the trap. Section III_2 is an area controled by wedgeout of Fengcheng group, Fengcheng group in this area has quite thick lithology so that It has beneficial resevoir phase belt. It can accumulate oil in itself or accept some oil in Jiamuhe group. Jiamuhe group has some oil accumulation condition in this area. Thus, section III_2 is jiamuhe-Fengcheng multiple petroleum accumulation belt, such as Ke 80 well. 8. The goal of exploration is suggested: Depositional trap or combination trap is the important aspect in later exploration. Both types of traps are the goal of the next drilling: Fault block trap in the east of 576 well and the NO. 2 fault block trap in the north of Ke 102 well It is suggested that we should study the law of oil and gas in Jiamuhe group and enhance the study of combination in forming reservoir and trap scale. We do some lithology forecast and reservoir diatropic forecast in order to know the area of oil and gas.