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1.
The problem of vibration isolation for the multi supporting machine installed on flexible foundations was studied by power flow and four end parameters methods.The general model of machine,isolator and flexible foundations was founded,and the transmission characteristic of the vibration system is analyzed.The expressions of power flow of the system with wave propagation effect being concerned was also presented.Finally,the effect of foundation flexibility and wave propagation on isolation was analyzed in detail.  相似文献   

2.
冬枣花药愈伤组织的诱导及原生质体分离   总被引:4,自引:1,他引:3  
【研究目的】研究冬枣花药愈伤组织的诱导,悬浮系的建立和培养及愈伤悬浮系原生质体的分离。【方法】以冬枣花药为试材,通过选择愈伤诱导培养基和原生质体分离所用酶的浓度找到最佳诱导和分离条件。【结论】使用1/2MS基本培养基附加TDZ0.2mg/L、NAA0.5 mg/L和 PVP2.0g/L,对诱导冬枣花药愈伤组织有较好效果;愈伤组织增殖采用培养基1/2MS+TDZ0.4 mg/L +NAA0.2 mg/L;悬浮细胞系培养采用1/2MS+TDZ0.4 mg/L +NAA0.2mg/L液体培养基;冬枣花药愈伤组织悬浮系原生质体分离时以0.6M甘露醇+0.1%MES+20~25 g/L纤维素酶,酶解时间为16h时得到的原生质体产量和活力较高。  相似文献   

3.
The study object of this paper is helical beveloid gears with parallel axis. Based on the gear Mshing Principles and the tooth-surface equations of pinion and gear,the mathematical model of tooth contact is developed under standard installation and installations with center distance error,axis error and multiple error respectively. The MATLAB solver is used to obtain the contact trace and the transmission error under different installing conditions and the comparative analysis is made. The results indicate that this gear drive is sensitive to axis installation errors,it forms the edge contact and cause the periodic transmission error. It can provide the foundation for designs and analysis of this gear transmission.  相似文献   

4.
By means of the substructure approach in the frequency domain, equations of motion of the rubber - isolated structures are established considering the soil-structure dynamic interaction. The seismic responses of two shear-type base-isolated structures with an embedded rigid rectangular foundation are numerically simulated, and the influences of the different rigidities of soil on the effect of the base isolation and the seismic responses of the structure are investigated. It is concluded that rubber bearing isolation can reduce the dynamic characteristics of structures and reduce displacement of floor and basement relative to ground. Meanwhile, considering the dynamic soil-structure interaction may reduce the isolation effect of the rubber-isolated structures and the effect level is in direct proportion to the stiffness of the superstructure and inverse proportion to the stiffness of foundation soil.  相似文献   

5.
Experiments are conducted using an integrative biomass pyrolysis liquefaction installation to extract liquid fuel via a fast pyrolysis of biomass. With several representative biomasses being used as raw materials, we investigate ways to affect the pyrolys  相似文献   

6.
辣根叶片原生质体分离条件的研究   总被引:1,自引:0,他引:1  
分离优质原生质体是进行细胞功能性以及生物膜特性研究的基础,建立适宜的"酶液浓度与酶解时间以及酶液渗透压"组合是获得高产优质原生质体的重要条件.本实验以辣根叶片为材料,研究了不同酶液浓度、溶液渗透压以及酶解时间对其原生质体分离的影响.结果表明,用浓度为1%纤维素酶+0.1%果胶酶+0.9mol/L甘露醇组成的混合酶液,在28.5℃条件下,pH为5.8的酶液组合中酶解50min时,可获得较高的原生质体产量,且原生质体活力较高.  相似文献   

7.
为了促进开发利用更多植物源功能活性多肽,本文归纳总结了植物源功能活性多肽提取、制备、分离、鉴定和功能验证等方面的研究,比较分析不同研究方法和应用结果的差异,总结了当前植物源功能活性多肽研究主要存在问题,提出今后应在降低提取成本和加强标准体系建设等方面开展工作,为未来植物源功能性多肽研究奠定基础。  相似文献   

8.
麻疯树根腐病病原菌有性阶段的调查及鉴定   总被引:1,自引:1,他引:0  
调查研究麻疯树根腐病主要病原菌--镰孢菌(Fusarium sp.)的有性世代,为病害流行学及其防治工作提供科学依据。通过实地调查、标本采集、分离培养、致病性测试、形态特征观测等,结合相关文献资料,确认麻疯树根腐菌的有性世代及其分类地位。结果表明在阴蔽潮湿以及具多个种源混栽的环境条件下,麻疯树根腐病的病原菌能够产生有性世代;致病性接种试验结果表明该有性世代能够导致寄主植物感病,其再分离培养物具有无性世代的典型特征;通过对有性世代的形态特征进行细致观测,将其鉴定为Haematonectria haematococca (Berkeley & Broome) Samuels & Nirenberg,其无性世代同时被确认为腐皮镰孢菌Fusarium solani(Martius)Appel & Wollenweber。麻疯树腐皮镰孢菌在特定条件下能够产生有性世代;避免多个种源混栽、通风透光、降低空气湿度是避免病原菌有性世代发生、减缓病害发生发展速度的一个重要措施。  相似文献   

9.
生物实验流程管理是生物实验室信息管理系统的核心,我们针对生物实验室实验流程灵活,数据流网络复杂等特点,设计了一套生物实验流程管理模型(Biological experiments flow management model,简称BioEFM),为生物实验室信息管理系统软件(Biology Laboratory Information Management System Software,缩写为BioLIMS)的开发提供了理论基础,大大提高了BioLIMS的开发效率。在此基础上开发的生物实验室信息管理系统软件(BioLIMS)应用于水稻基因组测序实验的信息管理中,为水稻基因组测序实验提供了灵活、便捷、高效的实验信息管理工具,为水稻基因组测序及后续的生物信息学分析奠定了良好的基础。  相似文献   

10.
低聚木糖分离纯化技术的研究概述   总被引:4,自引:0,他引:4  
低聚木糖是功能性低聚糖类中功能较好的一种,工业应用范围广泛。综述了低聚木糖的常见分离纯化技术,对国内外低聚木糖的脱色、脱盐和单组分分离技术进行了简要的介绍。  相似文献   

11.
安学武 《中国农学通报》2020,36(16):143-148
为实现分布式测量的农业小气候观测系统设计,需要设计一种体积小、成本相对较低的观测传感器。设计中应用STM32系统,采用现代电子设计技术及智能化的软硬件开发,实现传感器的设计制造。结果表明,应用STM32系统进行主控单元硬件设计,及STM32系统自带的标准库函数开发固化软件,不仅功能上能够满足要求,而且设计及生产成本均较低。设计完成的一体式传感器不仅能够更好地满足农业小气候观测需求,而且较集中控制方式的农业小气候观测系统有安装维护上的优势,其体积小,而且“全无线”设计,不会影响农事活动。基于物联网的智能化传感器设计为实现分布式测量打下了基础。  相似文献   

12.
Because of their machining characteristics,Klinglnberg' s sprial bevel gears have the advantage over Gleason' s in many ways,so that they are more and more widely used. This paper analyzes the meshing and machining properties of the gears and deduces the equations,normal curveture and contact ratio of tooth surface. It also lays a solid foundation for spreading and importing the Klinglnberg' s machine,and developing klinglnberg' s gears.  相似文献   

13.
Combined with some engineering experiences,this paper primarily estabishes computer calculating models of simulating building thermal process and load estimation index,with orthogonal testing ways and square error analysis,and lays a foundation for researching the air_conditioning load property of office building by way of all_sidely investigating and analysing numerous factors of the building air_conditioning cooling load.Some experimental formulas are given finally.  相似文献   

14.
水稻逆转座子的研究现状   总被引:1,自引:0,他引:1  
逆转座子是水稻转座因子的一个主要组成部分。本文介绍了水稻活性逆转座子的发现、分离以及到目前为止发现的活性最高的水稻逆转座子Tosl7的结构及其在遗传分析中的应用。同时概述了逆转座子对水稻进化的影响以及逆转座子研究中存在的问题和解决方法。  相似文献   

15.
芒果采后及贮藏生理研究进展   总被引:3,自引:0,他引:3  
芒果是跃变型水果。采收后果实品质和代谢生理等发生重大变化,笔者从芒果果实的采后品质变化、呼吸强度、乙烯代谢、活性氧代谢、Ca2+对果实后熟的影响、逆境生理及不同采后处理对芒果采后生理的影响等方面,阐述了芒果采后和贮藏过程中的主要生理变化的研究进展,并指出了今后芒果采后保鲜的研究方向和研究内容。  相似文献   

16.
Combined with the design practice in foundation excavation engineering,the problems for combined supporting from inner supports and composite soil nailing wall under binary geological conditions,including soil layers and rock stratum with weak intercalation in range of excavation depth,are analyzed.These problems mainly include the following: calculation model of earthen pressure,the local bearing capacity of foundations below steel pipe piles,stiffness coordination at the junction of rigid and flexible supports,internal bracing stability influencd by restrained condition of upright post,etc.Problems of concern for design of similar foundation pit supports are pointed out,and measures for solving these problems are proposed.All these can provide references for similar projects.  相似文献   

17.
The robust control theory is used to solve the uncertainty of the optical extra-precise vibration isolation system. The wavelet theory is used to analyze the random vibration signal in the time-frequency domain and get the low frequency signal from the random vibration signal. The robust controller designed by the robust control theory is used to restrain the low frequency vibration. The active vibration isolation exploits the theory of robust control, which overcomes the uncertainty of model and the disturbance, and makes the control system to restrain the uncertainty of the model and the disturbance of the vibration. The simulation results prove that this method has shown good robustness and control precision in the vibration isolation of the optical extra-precise instrument and have good performance on restraining the low frequency vibration.  相似文献   

18.
水稻种子总RNA提取在水稻分子遗传基础实验中起着非常重要的作用,然而,高质量水稻种子RNA的获取难度高,极大阻碍了cDNA文库构建、RNA-Seq和基因表达分析等相关研究工作的开展和深入。为了探讨水稻种子总RNA提取的相关影响因素,寻找合适的水稻种子总RNA提取方式,本研究通过比较Trizol法、GeneMark试剂盒法和艾德莱试剂盒法3种不同的提取方式、不同的耗材处理方法、研磨方式等不同因素改进水稻种子总RNA的提取效果。不同的检测结果显示,艾德莱多糖多酚提取试剂盒能够提取到28S、18S条带完整、降解少和纯度高的水稻种子总RNA;不同耗材处理方法中,蛋白酶K处理过的耗材提取的总RNA比另外两种方法处理过的耗材提取的总RNA降解更少,28S和18S条带更清晰和完整、总RNA质量最高、效果最好;而研磨方式上,液氮冷冻研磨法能够有效抑制RNA酶对RNA的降解。本研究对水稻种子RNA提取过程相关因素的分析和改进,为促进以水稻种子为研究对象的分子实验奠定了一定的技术基础。  相似文献   

19.
调查陕西安康地区绞股蓝根结线虫的发生情况及危害种类,揭示绞股蓝连作与根结线虫的关系,旨在为绞股蓝根结线虫防治提供理论依据。对安康主产区6个调查点的绞股蓝根结线虫病进行取样调查,并采用形态学观察及rDNA-ITS序列分析方法进行分离鉴定。结果表明,在安康市绞股蓝主产区均发现了不同程度的根结线虫危害,严重的地块发病率高达75.4%,且发病情况随种植年限的延长和海拔的降低而逐渐加重。通过分离鉴定,确定了发生在安康地区绞股蓝上的根结线虫为南方根结线虫(Meloidogyne incognita)。目前未见绞股蓝上发现根结线虫危害的报道,这是首次报道陕西省安康地区绞股蓝上发生根结线虫,为进一步分析绞股蓝根结线虫种群及该病的防治研究奠定了基础。  相似文献   

20.
Along with the development of commodity economy, the charge way as to record water meters in turns is no more received by the people. It is an important reform in tap water charge system to introduce "one household one water meter" supported by the people. In this paper, several methods of "one household one water meter" installation and water meter level position installation form in details are introduced.A detailed analysis on its development trends and direction is carried out and it is pointed out that the "one household one water meter" installation will develop toward exposed wall and water meter room type level position installation. Finally, the charge way of IC card (TM Card) type and tele-metering water meter computer metering will be applied. This paper analyzes the hydraulic computation of "one household one water meter" and provides the hydraulic condition of "one household one water meter" installation.  相似文献   

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