整秆式甘蔗收获机内物流排杂高速摄影分析

为了研究整秆式甘蔗收获机内物流排杂运动机理,研制了甘蔗收获机内物流排杂试验台,并利用高速摄像机拍摄了甘蔗与蔗叶在物流通道内的运动全过程,并对图像进行分析。结果表明,甘蔗在物流运动过程中发生弹跳、扭转和弯曲变形,在剥叶运动过程中发生断尾,并且通过排杂装置将蔗叶与甘蔗分离后排出。通过建立甘蔗收获机内各部件元件与甘蔗、蔗叶的简化力学模型,结合甘蔗和蔗叶的力学特性分析了甘蔗和蔗叶在物流通道内的运动机理。甘蔗在物流运动中主要受到的作用力为各部件对甘蔗的轴向力、垂直于甘蔗运动方向的切向力和摩擦力。     

甘蔗叶鞘剥离过程弹性齿运动分析与试验

通过对弹性齿运动状态的分析阐述了弹性齿在叶鞘撕裂和剥离过程中的作用机理,采用ADAMS软件对弹性齿与甘蔗茎秆的接触过程进行仿真分析,确定剥叶滚筒中心距及弹性齿与甘蔗茎秆之间的相对速度变化对叶鞘撕裂和剥离产生的影响。利用物理样机进行剥叶滚筒中心距单因素试验和剥叶滚筒转速单因素试验对运动分析结果进行验证,并通过高速摄影对仿真的结果进行验证。结果表明,剥叶滚筒中心距为310 mm,弹性齿与甘蔗茎秆接触时刻,y轴方向的线速度差为3.91~5.87 m/s时,弹性齿可沿茎秆表面向下滑动,有利于叶鞘沿着纤维方向撕裂,x轴方向的线速度差为4.61~7.54 m/s时,弹性齿在甘蔗轴线方向可以持续滑动,有利于对叶鞘造成刮擦脱离,综合剥叶效果为含杂率低于7%、茎秆折断率低于15%。弹性齿与茎秆分离时刻,由于弹性恢复产生线速度突变,相对速度差增大4~5倍,有利于将叶鞘从茎秆上撕扯脱落。     

不同处理方法对滇重楼种子萌发及成苗的影响

通过对滇重楼种子进行不同处理,探讨其萌发时间、萌发率、成苗率的影响,选出最佳处理方法,以便今后指导实际育苗。进行去除假种皮、冷藏、不同浓度GA 3浸泡等对比处理,统计出(90,120,150,180,210 d)不同时间段的萌发情况及总萌发率和成苗率,并做方差分析。研究表明,假种皮对种子的萌发时间、萌发率、成苗率影响不大;低温冷藏对促进种子提早萌发有一定的作用;一定浓度的GA 3能够促进滇重楼种子的提前萌发,但浓度过高则会抑制种子的提早萌发,浓度为500 mg ·L ^-1 时萌发时间最佳;一定浓度的GA 3能提高滇重楼种子的萌发率及成苗率,浓度为300 mg ·L^-1 时相对萌发率(142%)及相对成苗率(158%)最大;但过高则会降低种子萌发率,减少成苗率,当GA 3浓度达到700 mg ·L^-1 时,萌发率及成苗率最低。     

Evaluation of Joint Toxicity of Enrofloxacin and Three Antimicrobials on MRC-5 Cells

The aim of this study was to evaluate the combined toxicity of enrofloxacin with each of three antimicrobials (ciprofloxacin,florfenicol and sulfamethazine).MRC-5 cells were used as a cell model to simulate the damage of lung cells caused by mixed contamination of antimicrobials.Multiple concentration gradients and mixing ratios were set.CCK-8 method was used to determine the inhibition rate of cell growth caused by four antimicrobials and the inhibition rate of cell growth caused by enofloxacin mixed with three antimicrobials,respectively.Then Chou-Talalay method was used to fit the median effect plot and to calculate the combination index (CI) value.The results showed that the growth inhibition rates of MCR-5 cells caused by four single drugs went up in a step-like manner with the increase of drug concentration in the tested concentration range,among them,the growth inhibitory rate of MCR-5 cells by florfenicol was low (<4.5%).The combined toxicity of the three binary combinations showed a concentration-dependent and mixing-ratio dependence.Mixing enrofloxacin and ciprofloxacin showed synergistic toxicity (CI<1) on MRC-5 cells at high and middle concentration groups,and antagonistic toxicity (CI>1) at the very-low-concentration groups.Mixing ciprofloxacin and florfenicol mainly showed an inhibited toxicity (CI>1).Binary combination enrofloxacin and sulfamethazine might present either a synergistic joint toxicity (CI<1) or an antagonistic joint toxicity (CI>1) as the concentration and mixing ratio changing.This study showed that it was necessary to assess the combined toxicity of antimicrobials in the toxicity evaluation of antimicrobials.Using Chou-Talalay method,the joint toxicity of multiple antimicrobials could be quickly and efficiently determined at cellular level.     

甘蔗收获机排杂风机设计与试验

为解决甘蔗联合收获机的排杂问题,设计了一种在甘蔗收获机排杂装置中使用的新型风机,并在试验台上进行了试验研究。以排杂风机出风口风速为试验指标,对风机转速、进风口方式和进风口面积进行了单因素试验。试验结果表明,风机最佳性能参数为：风机转速为1?800?r/min、进风口方式为轴向进风、进风口面积为16?475和19?119mm2、距离出风口为50?mm时,出风口风速最大。其5个测量点的风速平均值依次为：13.867、14、11.633、11.333、12.383?m/s。后期排杂试验表明,在此最佳参数下,风机排杂效果最佳。     

绥阳县洋川镇扑灭定点屠宰场猪炭疽疫情报告

绥阳县畜牧局兽防站于2001年10月22日上午8:45分接到洋川镇定点屠宰场检疫员报告,有一头病死猪(约240kg,末放血),疑似炭疽病,遂派人到场进行检查,发现尸僵不全,血液凝固不良,鼻孔有少量血液及血污,由于不能确诊,切开颌下淋巴结观察,其病变为淋巴结肿胀出血,呈酱红色,并取该淋巴结送市兽防站进一步作实验室检验,同时对场内活猪进行隔离观察,下午6时得到诊断结果,确诊为炭疽病(炭沉反应)随即组织了扑灭工作.现将有关情况报告如下:     

4GDZ-132型切段式甘蔗联合收割机研制

针对现有切段式甘蔗联合收割机输送通道易堵塞、含杂率与损失率高等问题,该研究设计了一种切段刀辊中置式两级通道甘蔗联合收割机。该机采用短路径整秆输送通道和刮板筛网式蔗段输送通道,采用中置+后置风机组成的双风机除杂系统,实现甘蔗根切、喂入、输送、切段、风选除杂和卸料等联合作业。通过计算确定了整秆输送通道安装角度与宽度、喂入与输送辊筒直径、切段刀辊外圆直径、蔗段输送通道刮板高度、风机位置等关键结构参数,以及喂入与输送辊筒转速、切段刀辊转速、除杂风机转速等关键作业参数,并研制了4GDZ-132型切段式甘蔗联合收割机样机。样机田间试验结果表明：在作业速度2 km/h、风机转速1 100 r/min时,含杂率为4.42%、总损失率为3.08%、蔗段合格率为92.10%、切割高度合格率为96.20%、宿根破头率为9.60%,整机作业性能指标满足切段式甘蔗联合收割机技术标准要求。     

恩诺沙星联合用药对MRC-5细胞生长抑制的研究

本研究旨在评价恩诺沙星分别与3种抗菌药（环丙沙星、氟苯尼考和磺胺二甲嘧啶）的联合毒性。选用MRC-5细胞作为细胞模型模拟抗菌药的混合污染对肺细胞的损害，设置多个浓度梯度和混合比例，采用CCK-8方法检测4种抗菌药单药对细胞生长的抑制率及恩诺沙星分别与3种抗菌药混合后对细胞生长的抑制率，而后使用Chou-Talalay方法拟合中值效应曲线，计算出联合指数（combination index，CI）。结果显示，在检测浓度范围内，4种单药对MCR-5细胞的生长抑制率随药物浓度增加均呈阶梯状上升，其中氟苯尼考对MCR-5细胞的生长抑制率较低（<4.5%）。3种二元药物组合的混合毒性均表现出了浓度依赖性和混合比例的依赖性，联合使用恩诺沙星与环丙沙星在高、中剂量组下对MRC-5细胞表现协同毒性（CI<1），极低剂量组下表现为抑制毒性（CI>1）；联合使用恩诺沙星与氟苯尼考对MRC-5细胞的毒性主要是相互抑制的（CI>1）；联合使用恩诺沙星与磺胺二甲嘧啶对MRC-5细胞的毒性可能表现相互促进（CI<1），也可能表现相互抑制（CI>1），具体表现与给药剂量和浓度比值有关。本研究表明，在抗菌药的毒性评价中，评估抗菌药的联合毒性是有必要的，使用Chou-Talalay方法可快速高效地完成细胞水平上对抗菌药联合毒性的评估。     

一例水牛狂犬病病例报告

2004年11月29日,绥阳县枧坝镇菁口村发生疑似狂犬病疫情,请求派人处理,我们连夜赶到发病地点进行调查。现将调查情况报告如下。     

Biodegradability of Di(2-Ethylhexyl) Phthalate by Pseudomonas Fluorescens FS1

Di(2-ethylhexyl)phthalate (DEHP), one of high-molecular weightphthalate esters (PAEs), is used in the manufacturing of polyvinylchloride (PVC) resins, polyvinyl acetate, cellulosics,and polyurethanes, and contributes to environmental pollution. In this article, the characteristics of DEHP biodegradation by aneffective degradation bacterium, Pseudomonasfluorescens FS1 that isolated from the activated sludge at a petrochemicalfactory, was capable of using phthalate esters as the sole carbonand energy source, were investigated. Experimental results showedthat the biodegradation of DEHP by P. fluorescens FS1 could be described by the first-order reaction model, whichcould be expressed as: lnC = –0.0688t + A, and the half-life ofDEHP biodegradation was 10.07 d when the initial concentrations of DEHP were less than 50 mg L^-1. The inhibition effects ofDEHP as a substrate had become predominant above the concentration of 50 mg L^-1. The PAEs-degrading enzyme of P. fluorescens FS1, mainly located in the soluble part andthe particle of cytoplasm, was an intracellular enzyme. The metabolites of DEHP degradation by P. fluorescens FS1, which monoester, phthalic acid, benzonic acid, phenol, wereextracted using dichloromethane at different time intervals and identified by the GC-MS. The tentative pathway proposed for degradation of DEHP by P. fluorescens FS1 under aerobic condition is monoester in the beginning, further enzymatic degradation of the monoester produces phthalic acid, benzonic acid, phenol and finally CO₂ and H₂O.