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 共查询到11条相似文献,搜索用时 62 毫秒
1.
采用明胶平板筛选法从植物防风的根中分离得到一株高产蛋白酶的内生菌株FFR3.结合生理生化特性和16S rDNA序列分析,初步鉴定此菌株为类芽孢杆菌Paenibacillus sp..以胞外蛋白酶活力为指标,对内生细菌FFR3的产酶培养条件进行初步研究.结果表明:5 g/L葡萄糖和7.5 g/L酵母浸膏是菌株生长产酶的较适碳源和氮源;无机盐MgSO_4·7H_2O、KH_2PO_4和FeSO_4·7H_2O浓度分别为3、5和0.1 g/L时有利于胞外蛋白酶的产生.菌株在发酵培养条件为2%接种量、50 mL/250 mL装液量、pH 7.0、转速180 r/m,温度37℃时,发酵48 h可获得较高的酶产量,蛋白酶活力可达633.19 U/mL,较初筛时的酶活力提高15.94倍.  相似文献   

2.
The objective of this research was to examine if certain strains of Bacillus bacteria, could survive in dry powder products and if so, could the bacteria degrade organic contaminants in saline wastewater on a ship. As part of the study, we isolated 7 domesticated strains named NY1, NY2,..., and NY7, the strain NY6 showed to have the best performance for organic matter degradation and could survive in dry powder more than 3 months. NY6 was identified as Bacillus aerius, based on the morphological and physic-chemical properties. Its optimal growth conditions were as follows: salinity was 2%; temperature was 37°C; pH was in 6.5–7.0; best ratio of C: N: P was 100:5:1. The capability of its dry powder for Chemical Oxygen Demand (COD) removal was 800mg COD/g in synthesized marine wastewater with 2% salinity. The spores in the dry powder were 1.972×108 g ?1.  相似文献   

3.
基于485总线的温度监控系统设计   总被引:1,自引:1,他引:0  
介绍一种基于485总线的温控系统的设计与实现.系统采用上位机和下位机设计,下位机通过温度传感器监测温度,与预置温度比较后执行任务;上位机和下位机通过主从应答方式交换数据信息.在上位机端的PC上实现对多路传感器传来的温度信息入库保存、打印、温度变化历史曲线绘制等功能.  相似文献   

4.
张晓平  何琳  周炜 《船舶工程》2015,37(9):45-48
为提高隔振系统对低频微振动的隔离能力,研究了一种新型三磁体负刚度结构,分析了该结构产生负刚度的原理。将三磁体负刚度结构与隔振系统并联使用,在不影响原隔振系统载荷性能的情况下可降低系统的固有频率。分析了隔振器刚度及磁体间初始间隙对并联系统刚度特性的影响,提出从稳定性和隔振性能两方面来进行低频隔振系统设计。  相似文献   

5.
In this article we describe the development of a tool that allows planners to efficiently and effectively plan space within valuable areas of a shipyard. Traditionally, space is considered as resource; however, it is difficult to accurately account for and plan its consumption with the currently available planning software’s. The spatial scheduling tool described in this article can be used by planners to manually or automatically reserve space within the shipyard for construction of large blocks over the entire erection period of the ship. The software is coupled with a heuristic optimization solver inspired by an algorithm used for "3D bin-packing problems." The result is the ability to efficiently generate and compare multiple space allocation alternatives in a reduced time with the ultimate goal of maintaining the critical ship erection schedule. A better solution than manual or semi-automatic allocation of blocks can be obtained through the optimization module.  相似文献   

6.
利用舰船火灾区域模拟及烟气组分浓度的计算方法,研究舰船舱室火灾发生时舱室内的有害烟气成分随时间的变化情况,得出舱室内的有害烟气成分分布图,可供舰船消防设计和舰船消防管理参考。  相似文献   

7.
为了实现中国海事“十一五”发展的宏伟目标,做好建设规划的前期工作,交通部海事局于2D06年1月13 日至14日在北京召开直属海事系统“十一五”建设规划前期工作会,交通部海事局常务副局长刘功臣、党委书记梁晓安、副局长郭莘等领导出席会议并发表重要讲话。交通部综合规划司庞松副司长、崔学忠处长介绍了  相似文献   

8.
Unsteady Reynolds averaged Navier–Stokes (URANS) computations of standard maneuvers are performed for a surface combatant at model and full scale. The computations are performed using CFDShip-Iowa v4, a free surface solver designed for 6DOF motions in free and semi-captive problems. Overset grids and a hierarchy of bodies allow the deflection of the rudders while the ship undergoes 6DOF motions. Two types of maneuvers are simulated: steady turn and zigzag. Simulations of steady turn at 35° rudder deflection and zigzag 20/20 maneuvers for Fr = 0.25 and 0.41 using constant RPM propulsion are benchmarked against experimental time histories of yaw, yaw rate and roll, and trajectories, and also compared against available integral variables. Differences between CFD and experiments are mostly within 10 % for both maneuvers, highly satisfactory given the degree of complexity of these computations. Simulations are performed also with waves, and with propulsion at either constant RPM or torque. 20/20 zigzag maneuvers are simulated at model and full scale for Fr = 0.41. The full scale case produces a thinner boundary layer profile compared to the model scale with different reaction times and handling needed for maneuvering. Results indicate that URANS computations of maneuvers are feasible, though issues regarding adequate modeling of propellers remain to be solved.  相似文献   

9.
A finite-element method coupled with analysis of a noncavitating lifting surface was used to assess the performance of a marine propeller, including the thrust, torque, efficiency coefficients, and deflections. The formulation used displacements as unknowns in the structural part and the strength of the vortex as unknowns in the fluid part. A coupled matrix derived from the Bernoulli equation and hydrostatic pressure in terms of the strength, of the vortex enforced coupling between the fluid and the structure. The resulting matrix equation was unsymmetric and nonlinear; a Newton-Raphson procedure was used to solve this equation. The numerical results were compared with test data; computed and measured values agreed satisfactorily. We also investigated the effect of blade thickness on the performance and strength of the propeller. We did not consider the fatigue strengh of the propeller in this analysis.  相似文献   

10.
  目的  研究弹性螺旋桨在水流中的振动响应特性。  方法  基于CFD/FEM流固耦合方法,利用Work-bench平台中的ANSYS-CFX模块对螺旋桨进行双向流固耦合水动力求解,分析弹性螺旋桨变形及应力应变响应特性;考虑到流固耦合对固有特性的影响,利用ACT_Acoustic模块计算桨叶湿模态,结合弹性螺旋桨固有特性和流固耦合水动力结果进行弹性螺旋桨频谱分析。  结果  流固耦合水动力结果相较不考虑流固耦合的定常计算结果更接近试验回归曲线;与干模态相比,弹性螺旋桨前5阶湿模态固有频率减小19%~37%,且四阶和五阶干湿模态振型存在交错情况。频谱分析结果表明,水动力轴向推力和扭矩是弹性螺旋桨在流场中振动响应的主要影响因素,且主要引起弹性螺旋桨的一阶湿模态悬臂振动;桨叶面上,从叶梢处到导边和叶中部分,再到随边部分,最后到叶根处,结构响应逐渐降低。  结论  所做研究可为弹性螺旋桨流固耦合计算分析提供方法途径,也为螺旋桨流固耦合振动噪声分析打下了一定基础。  相似文献   

11.
As technical incentives, Ship Energy Efficiency Management Plan and Energy Efficiency Design Index, became the guidance for shipping companies in low-carbon shipping (LCS) integration. Despite the diversity of LCS measures, a mechanism to prioritize them is still urgently required from the view of shipping stakeholders. This paper developed a LCS measures prioritization mechanism for vessels relied on the combination of Fuzzy-based Technique for Order Preference by Similarity to Ideal Solution (FTOPSIS) and Fuzzy Quality Function Deployment (FQFD) so as to facilitate the treatment of uncertainties, thus realizing effective quantitative analysis of the LCS measures. Four performance aspects of LCS measures including ecological, reputation and competitive advantage, economic, and certainty level were analyzed and used for suitableness assessment, whereas weights of prioritizing criteria were determined by FQFD, alternatives were prioritized by FTOPSIS to build up a list of ranked LCS measures. The illustration example based on collected data of six alternatives was carried out to validate the feasibility of the methodology in prioritizing LCS measures. The outcomes can be used either as a stand-alone technique for prioritizing or as part of an integrated decision-making method for evaluating the effectiveness of chosen LCS measures.  相似文献   

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