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1.
深海沉积物保真采样技术及应用   总被引:1,自引:0,他引:1  
深海沉积物中含有大量嗜压型微生物和溢出性气体,采用传统取样技术不能长时间保持样品压力
,因而无法获取最真实的沉积物样品,为此提出了一套保真采样技术,可用于深海极端环境沉积物的取样
.通过对组成该技术的三个方面:样品转移技术、封口自紧技术与半主动保压技术进行研究,提出了保真
采样器的结构,分析了其工作原理,并对运用该理论的设备样机进行了实验室试验、码头试验和深海试验
研究.结果表明,基于上述理论的沉积物采样器样机具有良好的采样能力和原位压力保持功能.  相似文献   

2.
针对非保压取样方法难以获取高质量生物样本的问题,提出全海深宏生物保压取样器.考虑海上布放对装置质量的限制,提出中空式活塞取样结构.针对深海的超高压环境,分析常规蓄能器设计中理想气体状态方程的不适应性,提出基于真实气体状态的设计方法.针对密封圈移动引起的压降,设计液体主动补偿技术.内压试验结果表明,保压筒和取样活塞具有足够的强度和良好的密封性.高压舱测试表明,提出的取样系统在高压下可以稳定工作,设计的压力补偿系统能够显著地提高取样器的保压性能.取样器在马里亚纳海沟深度超过10 800 m深度时进行2次原位实验,共获取端足类生物保压样品174只.  相似文献   

3.
为了实现取样器保压取样的可靠性,深入分析了深海微生物取样器保压功能的实现过程及其主要
影响因素.根据蓄能器内气体状态参数和深海环境压力的变化,把取样器保压过程分成了4个关键状态,
并建立了蓄能器在各关键状态转变时的状态方程.计算研究和模拟试验表明,保压过程中蓄能器的开启压
力略高于蓄能器充气压力;提高蓄能器的充气压力能获得更好的保压效果,当样品的原位压力为60 MPa
、蓄能器充气压力为20 MPa时,采样筒可以获得59 MPa的保压效果,充气压力大于25 MPa以后,每升高5
MPa,采样筒的压力提高0.1 MPa;采用20 MPa的充气压力,蓄能器皮囊在最大工作压力下体积变化小于
公称体积的75%,仍有较大的补压余量.  相似文献   

4.
为了实现全海深沉积物保压取样,提出基于着陆器的自密封式全海深沉积物保压取样系统。针对着陆器承载能力有限的问题,设计了花瓣压缩环形取样、下端自封闭、两端自平衡的新型取样机构,避免了传统大口径球阀的设计。对取样器贯入过程进行分析,计算最大贯入力的值为786.5N,为验证计算结果,搭建了试验台架以模拟沉积物的取样过程,在不同性质的粘土中测试了取样性能和贯入力,试验结果与计算结果基本相符合。贯入-取样测试结果还表明,对于塑性和硬塑性粘土,所提出的取样机构具有较好的取样效果,而对于流塑性粘土,取样器的取样效果较差。基于所得的贯入力设计了传动和驱动机构,对驱动电机进行了选型和封装。为验证取样器在高压下的工作稳定性及保压性能,在60MPa和100MPa高压舱内进行了多次测试,试验结果表明,取样器能够保持测试压力的80%以上。最后,在中国2021大洋科考TS21航次中,搭载“奋斗者号”载人潜器在西菲律宾盆区和马里亚纳海沟进行了三次原位测试,所提出的取样器均完成保压取样任务,共获取保压沉积物样品710ml。本研究所提出的全海深沉积物保压取样系统,包括新型超高压保压取样机构设计,充油电机的封装技术,全海深保压取样器压力补偿技术等,为类似系统的设计提供了理论和工程基础,可广泛应用于其他深海保压取样系统。  相似文献   

5.
并联和串联囊式蓄能器的理论分析和数字仿真   总被引:3,自引:0,他引:3  
本文采用频率法,对新型串联囊式蓄能器衰减液压泵的压力脉动效果进行了理论分析和计算机仿真。并与常规并联囊式蓄能器作了比较,结果表明,串联囊式蓄能器对液压泵压力脉动的衰减效果远优于并联囊式蓄能器,所设计的新型串联囊式蓄能器,可推广应用于生产实际中。  相似文献   

6.
本文全面系统地阐述了流动粮食自动扦样器的研制,流动粮食自动扦样器的研制成功,解决了在实施“流动粮食扦样法”时没有理想扦样工具的矛盾,克服了包装扦样法的不足.设计出的样机实现了流动面粉、大米取样自动化,所取样品不影响其固有质量,具有代表性,样机性能良好,符合国家标准“流动粮食取样”要求.  相似文献   

7.
粒料层过滤是油田采出水处理系统普遍采用的工艺,与其粒料层的选择和布置一样,粒料过滤器的布水均匀性特征直接影响采出水的净化处理效果。利用Gambit建立模型并生成非结构化网格,基于Fluent软件中的DPM 模型模拟计算了过滤器内部压力场分布、过滤沿程压降特征、粒子运动迹线特征及粒料层表面的粒子分布与聚集行为,进而描述了油田常用压力式过滤器的布水特征,并进行了布水工艺优化。结果表明,相比于“条缝式” 布水模式的过滤器,“筛管式”布水更为均匀,不同处理量下的过滤轴线压降平均低出30.56%,且9筛管模式布水工艺的布水均匀性特征量能取得更为优越而稳定的分布。  相似文献   

8.
海水重金属自动检测系统研究   总被引:5,自引:0,他引:5  
基于电化学溶出伏安法研制了一种新型重金属检测系统,实现海水中锌、镉、铅、铜、锰、砷、铁和铬8种重金属元素质量浓度的自动检测。海水经过预处理后,8种重金属元素被分离为3路进入检测系统,锌、镉、铅、铜为一路,锰、砷为一路,铁、铬为一路。系统以银基汞膜电极为电化学传感器,通过PC机多线程控制三路恒电位仪电路、各蠕动泵和电磁阀,实现自动进样、检测和清洗。采用标准加入法进行定量分析,检测下限达到10-6 g/L。每路只需要6 mL样品,一次测量可以在30 min内完成。系统体积小、成本低、可以连续测量,适于现场在线自动监测海水中的重金属浓度分布。  相似文献   

9.
膜分离技术纯化绞股蓝皂苷   总被引:1,自引:0,他引:1  
以固形物得率和绞股蓝皂苷含量为评价指标,进行陶瓷膜和超滤膜过滤实验,对操作压力、溶液温度和膜的规格进行优选.结果表明:选择孔径0.5μm的陶瓷膜,在溶液温度40℃、过滤压差0.24MPa条件下,能达到较好去除提取液中的悬浮物和大分子杂质的效果;选择截留分子量为3×10^4的超滤膜,在溶液温度40℃、操作压力0.8 MPa条件下,去除小分子杂质和截留绞股蓝皂苷的效果较好.采用膜分离技术可以有效地分离纯化绞股蓝皂苷,该工艺操作简单、可靠,纯化效率高.  相似文献   

10.
液压储能式车辆制动能量回收系统参数设计研究   总被引:1,自引:0,他引:1  
通过蓄能器存储能量的计算公式,分析了蓄能器的容积、充气压力和最高工作压力对能量存储能力的影响,提出了充分发挥蓄能器能量存储能力的充气压力的确定方法和蓄能器容积的确定方法.根据能量守恒原理,得到了车轮制动力矩的计算公式,分析了液压系统的压力、液压泵/马达的排量和传动系的传动比对车轮制动力矩的影响,提出了液压泵/马达的排量和减速箱传动比的确定方法.  相似文献   

11.
针对空气源热泵工作时能效比会随着气温下降而明显降低的问题,在空气源热泵上增加了一级蓄热装置。在MATLAB下对单级蓄热器空气源热泵进行仿真,结果表明增加蓄热装置可以平衡空气源热泵的能效比。以太原最冷月统计24 h平均温度为前提,模拟蓄热器在不同质量的蓄热材料、不同长度的蓄热管和放热管下的不同表现。仿真结果表明,最优换热材料质量为170 kg,蓄热管为30 m,放热管为8 m。  相似文献   

12.
针对集成膜法海水软化技术及装置对海水纳滤前的分离粒度及效率的要求,开发出内置螺旋导流板和曲线长锥体的新型α旋流器。对4种尺寸相同但结构不同的α旋流器进行水、砂物系的分离实验研究,并测定了压降、分流比、进口流速对分离效率的影响。结果表明:相同操作条件下,新型α旋流器分级效率较好,对于粒径5μm的颗粒分离效率达到90%;当分流比为0.87时,其分割粒径d50为1.3μm。  相似文献   

13.
液压挖掘机回转制动能量回收系统   总被引:2,自引:0,他引:2  
为了回收液压挖掘机在回转阶段的制动能量,提出一种基于回转马达进/出口压力差自动识别回转过程所处阶段,决策能量回收的全液压自动控制回转制动能量回收系统.引入一正态分布函数,以蓄能器压力状态(SOP)、液压泵出口压力以及负流量反馈压力为输入信号,根据负载的实时需求功率,提出一种以复合恒功率 负流量动力控制决策发动机和蓄能器主辅动力源的能量分配方法,保证回转机构的正常高效运转.仿真结果表明,当回转系统作为单独执行机构时,采用该回收系统的液压挖掘机,能够实现高达50.0%的再生制动能量用于驱动回转的能量回收利用效率,在相同工况下比同吨位液压挖掘机节能16.3%,不影响操作习惯和操作性能.  相似文献   

14.
利用陶瓷膜过滤、钙盐沉淀法以及活性炭脱色等工艺从D-丙氨酸发酵液中提取D-丙氨酸,并对工艺条件进行了研究。经试验研究表明,陶瓷膜过滤能有效去除D-丙氨酸发酵液中的菌体,D-丙氨酸的平均收率为98.55%。利用钙盐沉淀法能够有效地除去发酵液中大量的SO2-4,最后利用活性炭脱色能够去除色素和其他杂质。通过单因素试验和正交试验确定了最佳的脱色条件为:活性炭的添加量为0.75%,脱色温度95℃,脱色时间70min、搅拌转速200r/min。脱色液经过浓缩结晶、离心分离、烘干后得D-丙氨酸成品,总提取收率平均为68.11%,产品质量符合日本味之素企业(AJI97)标准。  相似文献   

15.
为了获得活塞泵增压系统起动特性和工作特性,基于AMESim仿真平台建立了仿真模型.对活塞泵增压系统起动过程和稳态工作过程进行了仿真,给出了不同部位压力变化情况,以及蓄压器对泵出口压力的影响、流量对泵工作频率的影响.结果表明活塞泵增压系统起动迅速,工作过程中能够维持较高的泵出口压力.实际试验中增压系统参数变化趋势与仿真结果一致,验证了仿真方法和仿真模型的正确性。  相似文献   

16.
Using hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle as a simulation example, the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle were simulated and discussed with SIMULINK software and hydraulic control theory. The results show that the dynamic characteristics of hydraulic power steering system are improved obviously by using bladder accumulator, the hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle generates vibration at the initial stage under the normal steering condition of pulse input, and its static response time is 0.25 s shorter than that without bladder accumulator. Under the normal steering working condition, the capacity of steering accumulator for absorbing pulse is directly proportional to the cross section area of connecting pipeline, and inversely proportional to the length of connecting pipeline. At the same time, the precharge pressure of nitrogen in steering accumulator should he 60%-80% of the rated minimum working pressure of hydraulic power steering system. Under the abnormal steering working condition, the steering cylinder piston may obtain higher motion velocity, and the dynamic response velocity of hydraulic power steering system can he increased by reducing the pressure drop of hydraulic pipelines between the accumulator and steering cylinder and by increasing the rated pressure of hydraulic power steering system, hut the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle have nothing to do with the precharge pressure of nitrogen in steering accumulator.  相似文献   

17.
本文按粉磨系统的工况参数对袋式收尘器进行了试验,分析了过滤风速、入口含尘浓度、喷吹压力及脉冲宽度对粉尘负荷压降的影响程度,确定了结构压力损失、再生滤袋压力损失与过滤风速的关系式及粉尘负荷压力损失与过滤风速、入口粉尘浓度的关系式,提出了合理的喷吹制度的参数范围,讨论了应用过程中遇到的问题。  相似文献   

18.
It is the purpose of the present paper to convert hydraulic energy to electric energy and saves both the pressure and electrical energy for re - use during the next system upstroke using two secondary units coupled to induction motor to drive cylinder loads. During upstroke operation, the variable pump/motor (P/M) driven by both electric motor and the second (P/M) works as hydraulic pump and output flow to the cylinders which drive the load. During load deceleration, the cylinders work as pump while the operation of the two secondary units are reversed, the variable (P/M) works as a motor generating a torque with the electric motor to drive the other (P/M) which transforms mechanical energy to hydraulic energy that is saved in the accumulator. When the energy storage capacity of the accumulator is attained as the operation continues, energy storage to the accumulator is thermostatically stopped while the induction motor begins to work as a generator and generates electricity that is stored in the power distribution unit. Simulations were performed using a limited PT2 Block, i.e. 2nd-order transfer function with limitation of slope and signal output to determine suitable velocity of the cylinder which will match high performance and system stability. A mathematical model suited to the simulation of the hydraulic accumulator both in an open-or close-loop system is presented. The quest for improvement of lower energy capacity storage, saving and re-utilization of the conventional accumulator resulting in the short cycle time usage of hydraulic accumulators both in domestic and industrial purposes necessitates this research. The outcome of the research appears to be very efficient for generating fluctuation free electricity, power quality and reliability, energy saving/reutilization and system noise reduction.  相似文献   

19.
A new method was developed for effective enrichment of Cd2+ ions from water with a calcium alginate(CaAlg) hydrogel filtration membrane. First, the CaAlg hydrogel filtration membrane was prepared without a pore-forming agent. This membrane was used to remove Cd~(2+) via ion exchange with Ca~(2+), and the Cd~(2+) was preserved in the CaAlg hydrogel. Then, the CaAlg hydrogel containing Cd~(2+) was soaked in a sodium citrate solution, and the hydrogel was fully dissolved. The removal rate of the CaAlg filtration membrane reached almost 100% within 120 min when the Cd~(2+) concentration was under 1 mg/L. Factors affecting the removal rate were investigated, such as NaAlg concentration, operating pressure, operating time and the initial concentration of Cd~(2+). The effects of initial Cd~(2+) concentration, pressure and filtration time on the enrichment factor were also investigated. The results show that the enrichment factor reached 87.3 when the pressure was 0.18 MPa and the filtration time was 240 min. Different enrichment factors could be achieved by adjusting the operating pressure and filtration time.  相似文献   

20.
A new dual-layer granular bed filter for hot gas cleanup was invented and studied experimentally. Fine sand, 0.5-1 mm grain size and about 1350 kg/m^3 bulk density, was used as the lower layer of the filter. Expanded perlite particles, 2-5 mm grain size and about 70 kg/m^3 bulk density, was used for the upper layer of the filter in this study. It was confirmed that the sizes and densities of these two media matched well; the binary media remained in complete segregation during regeneration by fluidization. Test results show that the filtration of the expanded perlite particle layer was characterized as "deep bed filtration." Filtration of the fine sand layer was "surface cake filtration." The expanded perlite particle layer contributed about 90% to the bed dust capacity, but only about 20% to the total bed pressure drop, which increased the bed dust capacity ten fold compared to a single-layer bed of the same sand and the same total bed pressure drop. The dust cake on the surface of the fine sand layer raised the collection efficiencies to over 99.99%.  相似文献   

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