毛兰素调节Slit2/Robo1信号通路对糖尿病肾病模型大鼠肾小球内皮细胞血管生成的影响

目的 探讨毛兰素对糖尿病肾病(DN)模型大鼠肾小球内皮细胞血管生成的影响及slit同源蛋白2(Slit2)/轴突导向受体蛋白1(Robo1)信号通路的作用。方法 采用高糖高脂饲料持续饲养雄性SD大鼠8周,ip给予链脲佐菌素35 mg·kg^(-1)制备DN大鼠模型。将DN模型大鼠分为模型组及模型+毛兰素10,20和40 mg·kg^(-1)组(ig给予毛兰素,持续8周),每组10只,同时设置正常对照组(ig给予0.5%羟甲基纤维素钠,持续8周)。尿蛋白定量试剂盒测定大鼠24 h尿蛋白水平,全自动生化分析仪检测血清空腹血糖(FPG)和血肌酐(Scr)水平,PAS染色观察大鼠肾组织病理变化,免疫荧光法检测肾组织血小板内皮细胞黏附分子31(CD31)和足细胞标志蛋白(PCX)表达水平,Western印迹法检测肾组织Slit2和Robo1蛋白表达。结果 与正常对照组比较,模型组大鼠FPG、Scr和24 h尿蛋白水平以及肾组织CD31、Slit2和Robo1蛋白表达显著升高(P<0.01);肾组织新增肾小球毛细血管,并出现肾小球肥大和系膜面积扩张,存在非管状CD31染色,缺少相邻PCX染色,以及部分CD31管状区域染色也缺乏相邻的PCX染色。与模型组比较,模型+毛兰素10,20和40 mg·kg^(-1)组大鼠FPG、Scr和24 h尿蛋白水平及肾组织CD31、Slit2和Robo1蛋白表达显著降低(P<0.05,P<0.01);肾组织新增肾小球毛细血管、肾小球肥大和系膜面积扩张现象减轻,CD31管状区域染色与PCX足细胞区域染色基本相邻。结论 毛兰素可能通过抑制Slit2/Robo1信号通路而抑制DN模型大鼠肾小球内皮细胞血管生成。

大豆异黄酮抑制Slit2/MAPK信号通路对牙周炎大鼠牙槽骨吸收和炎症反应的影响

目的:基于Slit同源物2(Slit2)/P38丝裂原活化蛋白激酶(MAPK)信号通路探讨大豆异黄酮(SIF)对牙周炎大鼠牙槽骨吸收和炎症反应的影响。方法:将大鼠分为对照组(Control)、模型组(Model)、SIF低剂量组(L-SIF,25 mg/kg)、SIF高剂量组(H-SIF,75 mg/kg),每组10只,除对照组外,其余各组使用丝线结扎大鼠上颌第一磨牙的牙颈部建立牙周炎模型。L-SIF组和H-SIF组大鼠灌胃相应剂量SIF,Control组和Model组灌胃等量生理盐水,1次/d,连续4周。给药结束后,ELISA检测大鼠血清Slit2、TNF-α、IL-6、IL-1β水平;Micro-CT扫描检测釉牙骨质界至牙槽骨嵴顶(CEJ-ABC)距离和骨矿物质密度(BMD)、骨体积分数(BV/TV),评估牙槽骨丢失情况;HE染色和抗酒石酸酸性磷酸酶(TRAP)染色评估组织炎症反应、骨吸收和破骨细胞活性;免疫组织化学法(IHC)检测牙周组织骨保护素(OPG)和核因子κB受体活化因子配体(RANKL)表达;Western blot检测牙周组织Slit2、P38 MAPK、p-P38 MAPK蛋白表达。结果:与Control组相比,Model组大鼠血清Slit2和TNF-α、IL-1β、IL-6水平、CEJ-ABC距离、牙周组织病理学损伤评分、破骨细胞数量、RANKL阳性表达、Slit2蛋白水平和p-P38 MAPK/P38 MAPK显著升高,BMD和BV/TV、牙周组织OPG阳性表达显著降低(均P<0.05);与Model组相比,L-SIF组和H-SIF组大鼠血清Slit2和TNF-α、IL-1β、IL-6水平、CEJ-ABC距离、牙周组织病理学损伤评分、破骨细胞数量、RANKL阳性表达、Slit2蛋白水平和p-P38 MAPK/P38 MAPK显著降低,BMD和BV/TV、牙周组织OPG阳性表达显著升高(P<0.05),且H-SIF组上述指标变化显著优于L-SIF组(P<0.05)。结论:SIF可抑制牙周炎大鼠牙槽骨吸收和炎症反应,改善牙周炎,其作用机制可能与抑制Slit2/P38 MAPK信号通路有关。

Young's double slit interference with vortex source

The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify the OV mode through the analysis of interference patterns. The interference patterns of the OV source incident on the double slits can be perfectly illustrated by using both the classical double-slit interference method and the Huygens–Fresnel principle. The interference fringes will twist along the negative or positive direction of x axis when topological charge(TC)l>0 or l<0, and the degree of the movement varies with the TC, allowing for a quantitative display of the OV characteristics through the interference patterns. Additionally, we deduce analytically that the zeroth-order interference fringe has a linear relationship with the TC and the vertical position. These findings highlight the ability to identify the OV mode by analyzing the interference patterns produced by Young's doublet.

Refinement of Adaptive Dynamical Simulation of Quantum Mechanical Double Slit Interference Phenomenon

We applied adaptive dynamics to double slit interference phenomenon using particle model and obtained partial successful results in our previous report. The patterns qualitatively corresponded well with experiments. Several properties such as concave single slit pattern and large influence of slight displacement of the emission position were different from the experimental results. In this study we tried other slit conditions and obtained consistent patterns with experiments. We do not claim that the adaptive dynamics is the principle of quantum mechanics, but the present results support the probability of adaptive dynamics as the candidate of the basis of quantum mechanics. We discuss the advantages of the adaptive dynamical view for foundations of quantum mechanics.

SLIT治疗BA的效果及对IL-17、IL-27水平和Th17/Treg平衡的影响

目的探讨舌下脱敏治疗(SLIT)支气管哮喘(BA)的效果及对白细胞介素(IL)-17、IL-27水平和辅助性T细胞(Th17)/调节性T细胞(Treg)平衡的影响。方法分析124名BA患者的临床资料。将患者随机分为观察组(n=62)和对照组(n=62)。两组入院后均接受常规治疗,对照组接受布地奈德福莫特罗粉吸入剂,观察组基于对照组加舌下含服粉尘螨滴剂。比较两组疾病控制情况、临床症状评分、及外周血IL-17、IL-27水平和Th17/Treg。结果观察组总控制率高于对照组(P<0.05)。治疗后,两组临床症状评分、Th17/CD4^(+)和Th17/Treg和观察组IL-17均低于治疗前,且观察组均低于对照组(P<0.05)。治疗后,两组IL-27、Treg/CD4^(+)均高于治疗前,且观察组高于对照组(P<0.05)。结论SLIT治疗BA具有良好的效果,可降低外周血IL-17水平,增加外周血IL-27水平,且纠正Th17/Treg免疫失衡。

宫颈癌组织SLIT3、SPARCL1表达及与术后复发的关系

目的 探讨宫颈癌组织SLIT3、SPARCL1蛋白表达与根治术后复发的关系。方法 选择2019年10月至2021年4月在医院接受宫颈癌根治术治疗的患者107例作为研究对象,并选择30例子宫良性病变手术切除患者作为对照组;随访1年根据随访结果分为复发组(n=25)和未复发组(n=82)。实时荧光定量检测(qPCR)组织SLIT3、SPARCL1 mRNA表达水平,免疫组化检测SLIT3、SPARCL1蛋白表达水平,分析SLIT3、SPARCL1蛋白表达与临床病理特征相关性,COX模型分析影响宫颈癌患者根治术后复发的危险因素。结果 107例根治术患者中25例患者复发,复发率为23.36%;SLIT3低表达患者术后复发率(31.15%)显著高于SLIT3高表达患者术后复发率(13.04%),SPARCL1低表达患者术后复发率(32.31%)显著高于SPARCL1高表达患者术后复发率(9.52%),差异有统计学意义(P <0.05)。宫颈癌组SLIT3、SPARCL1m RNA表达显著低于对照组,差异有统计学意义(P <0.05);复发组患者宫颈癌组织SLIT3、SPARCL1 mRNA水平显著低于未复发患者,差异有统计学意义(P <0.05)。宫颈癌组织SLIT3、SPARCL1蛋白表达与分化程度、临床分期、淋巴结转移、基质浸润深度相关(P <0.05),与年龄、病理类型、肿瘤最大径无关(P> 0.05)。COX单因素分析显示,分化程度、临床分期、淋巴结转移、基质浸润深度、SLIT3蛋白表达、SPARCL1蛋白表达与宫颈癌患者根治术后复发相关(P <0.05);COX多因素分析显示,中/高分化、Ⅱa分期、淋巴结转移、基质浸润深度> 50%、SLIT3蛋白低表达、SPARCL1蛋白低表达是影响宫颈癌患者根治术后复发的独立危险因素(P <0.05)。结论 宫颈癌组织SLIT3、SPARCL1水平均低于正常宫颈组织,SLIT3、SPARCL1蛋白低表达是影响宫颈癌根治术后复发的独立危险因素,对预测宫颈癌术后复发具有一定的临床意义。

The wave and vibratory power transmission in a finite L-shaped Mindlin plate with two simply supported opposite edges

In this paper,wave and vibratory power transmission in a finite L-shaped Mindlin plate with two simply supported opposite edges are investigated using the wave approach.The dynamic responses,active and reactive power flow in the finite plate are calculated by the Mindlin plate theory （MPT） and classic plate theory （CPT）.To satisfy the boundary conditions and continuous conditions at the coupled junction of the finite L-shaped plate,the near-field and far-field waves are entirely contained in the wave approach.The in-plane longitudinal and shear waves are also considered.The results indicate that the vibratory power flow based on the MPT is different from that based on the CPT not only at high frequencies but also at low and medium frequencies.The influence of the plate thickness on the vibrational power flow is investigated.From the results it is seen that the shear and rotary inertia correction of the MPT can influence the active and reactive power at the junction of the L-shaped plate not only at high frequencies but also at low and medium frequencies.Furthermore,the effects of structural damping on the active and reactive power flow at the junction are also analyzed.

Joint 2D DOA and Doppler frequency estimation for L-shaped array using compressive sensing

A joint two-dimensional(2D)direction-of-arrival(DOA)and radial Doppler frequency estimation method for the L-shaped array is proposed in this paper based on the compressive sensing(CS)framework.Revised from the conventional CS-based methods where the joint spatial-temporal parameters are characterized in one large scale matrix,three smaller scale matrices with independent azimuth,elevation and Doppler frequency are introduced adopting a separable observation model.Afterwards,the estimation is achieved by L1-norm minimization and the Bayesian CS algorithm.In addition,under the L-shaped array topology,the azimuth and elevation are separated yet coupled to the same radial Doppler frequency.Hence,the pair matching problem is solved with the aid of the radial Doppler frequency.Finally,numerical simulations corroborate the feasibility and validity of the proposed algorithm.

Laboratory test on the combined cooling effect of L-shaped thermosyphons and thermal insulation on high-grade roadway construction in permafrost regions

With the completion of the Qinghai-Tibetan Railway,economic development of related areas has been greatly accelerated.This,in return,calls for building or upgrading more roadways,especially high-grade roadways.In cold regions,the thawing of permafrost can induce settlement damage of and even failure to railway (or roadway) embankments.Thermosyphons (self-powered refrigera-tion devices that are used to help keep the permafrost cool) have proved effective in mitigating thaw settlement by maintaining the thermal stability of the embankments.However,for high-grade roadway embankments of great width,stabilizing or cooling ef-fects of traditional geotechnological measures may be limited.To enhance the cooling effect of thermosyphons,an L-shaped thermosyphon was designed.A laboratory test was carried out to study the combined cooling effect of the L-shaped thermosyphon and thermal insulation applying to roadbed construction.The angle between the evaporator and condenser sections of the L-shaped thermosyphon is 134 degrees,and the L-shaped thermosyphon was inserted into the soil at an angle of 5 degrees with the road surface.The tested results show that the L-shaped thermosyphon is effective in removing heat from a roadway in winter.When the ambient air temperature is lower than the soil temperature,the thermosyphon is active and extracts the heat in the soil around it.When the ambient air temperature is higher than the soil temperature,the thermosyphon is inactive,and no heat is in-jected into the soil through the L-shaped thermosyphon.Compared to embankments with straight thermosyphons,the inner parts of the embankments with L-shaped thermosyphons were significantly cooled.It is hoped that the present study would be useful to the application of L-shaped thermosyphons in the construction of high-grade roadways in cold regions.

Test on mechanical behavior of SRC L-shaped columns under combined torsion and bending moment

Investigations of the seismic behavior of steel reinforced concrete L-shaped columns under constant axial compression and cycled bending-shear-torsion load were performed.Six specimens,which considered two parameters,i.e.,the moment ratio of torsion to bending(γ)and the aspect ratio(column length-to-depth ratio,φ),were prepared for the experiment.In this study,the failure process,torsion-displacement hysteresis curves,and flexure-displacement hysteresis curves were obtained.The failure characteristics,mechanical behavior of specimens such as the failure patterns,hysteresis curves,rigidity degradation,ductility and energy dissipation,are analyzed.The experimental research indicated that the major failures of the specimens were bending failure,bending-shear failure and bending-torsion failure as the moment ratio of torsion to bending(γ)increased.The torsion-displacement hysteresis curves were pinched in the middle,formed a slip platform,and the phenomenon of“load drop”occurred after the peak load.The bending-displacement hysteresis curves were plump,which showed that bending capacity of the specimen was better than its torsion capacity.Additionally,the energy dissipation of the specimen was dominated by torsion in the early stage and ultimately governed by the bending moment in the later phase.Test results also indicated that the displacement ductility coefficient and interstory rotation angle of the failure point were less than 3.0 and 1/50,respectively,which means the test specimen performance does not meet the requirement of the Chinese Code for Seismic Design of Buildings(GB 50011-2014)in this respect.

Slit2和Robo1在浸润性乳腺癌中的表达及其临床意义

目的 观察Slit2和Robo1在浸润性乳腺癌的表达变化及其与浸润性乳腺癌临床病理指标的相关性,探讨Slit2/Robo1信号通路对浸润性乳腺癌病理过程的调控作用。方法 应用免疫组织化学法观察Slit2和Robo1在浸润性乳腺癌、乳腺纤维腺瘤和正常乳腺组织的表达;应用卡方检验或校正的卡方检验分析Slit2和Robo1在各组间阳性率差异;采用方差分析、Kruskal-Wallis或Mann-Whitney U检验分析Slit2和Robo1的免疫组织化学染色量差异;采用非参数Spearman等级相关分析检验Slit2和Robo1与浸润性乳腺癌临床病理指标相关性。结果 Slit2定位表达于细胞质;Robo1定位表达于细胞质和细胞核。Slit2和Robo1在浸润性乳腺癌的表达率和表达量明显低于乳腺纤维腺瘤和正常乳腺组织。在浸润性乳腺癌中,Slit2和Robo1具有高度相关性,且Slit2与ER、PR、Her2呈正相关(P<0.05);Robo1与ER、PR呈正相关(P<0.05)。Slit2/Robo1与浸润性乳腺癌患者年龄、淋巴结转移、肿瘤大小、病理分期和组织学分级无关(P>0.05)。结论 Slit2和Robo1在浸润性乳腺癌低表达,且与其发生、发展和预后存在相关性,提示Slit2/Robo1信号通路可能参与浸润性乳腺癌的病理过程,发挥调控作用。

Characteristics of debris flow impact on a double-row slit dam

To accurately predict impact loads can ensure the safe operation of debris flow control projects.The instantaneous impact process is usually considered in the calculation of the debris flow impact force;however,the redistribution of an impact load after structural regulation is unclear.In this study we deduced the theoretical calculation of a debris flow impact on a double-row slit dam,and carried out a verification experiment on the debris flow impact.The calculation model considers the influence of the debris flow properties,dam arrangement and pile material.The results show that the impact force of the debris flow is obviously affected by the bulk density.When the bulk density is 21 kg/m^(3),the maximum impact force on the pile dam is 1.15 times that when the bulk density is 15 kg/m^(3),but the time it takes for the debris flow to pass through the dam body is reduced by 60%.The larger the relative pile spacing,the more sufficient the flow space and the lower the maximum impact force.The maximum impact force of relative pile spacing of 0.8 is 12%less than that of elative pile spacing of 0.5.The horizontal distribution of the impact force in the mud depth range is parabolic.The maximum impact force on the centre pier is 1.3 times that of a side pier,and the maximum impact force on the dam body appears at the top of the mud depth range.From the vertical distribution of the impact force,the maximum impact force at the highest mud mark is approximately 70%of that of the bottom.With the increase in the relative pile spacing,the longitudinal maximum impact force distribution first decreases and then increases.

Multicut L-Shaped Algorithm for Stochastic Convex Programming with Fuzzy Probability Distribution

Two-stage problem of stochastic convex programming with fuzzy probability distribution is studied in this paper. Multicut L-shaped algorithm is proposed to solve the problem based on the fuzzy cutting and the minimax rule. Theorem of the convergence for the algorithm is proved. Finally, a numerical example about two-stage convex recourse problem shows the essential character and the efficiency.

H9N2禽流感病毒PB2蛋白627位点突变对小鼠肺脏RIP3、Slit2和Robo4表达和分布的影响

PB2蛋白627位点被证实是决定甲型流感病毒宿主范围和致病性的关键因子,为深入探究H9N2禽流感病毒(avian influenza virus,AIV)及其PB2蛋白627位点突变株对BALB/C小鼠肺脏RIP3、Slit2和Robo4基因表达和组织分布的影响,该研究使用H9N2 AIV(V_(K627))和该毒株PB2蛋白627位点突变株(rV_(K627E))感染BALB/C小鼠,分别在攻毒后第1、3、5、6 d采集肺组织,通过qRT⁃PCR和免疫组织化学技术对RIP3、Slit2和Robo4基因在小鼠肺组织中的特异性表达和分布进行研究。结果显示,攻毒组小鼠肺脏RIP3的表达量与对照组相比显著上升,同时VK627组RIP3的表达量显著高于rV_(K627E)组;Slit2和Robo4的表达量在攻毒后第1 d明显低于对照组,之后rVK627E组的表达量与对照组和VK627E组相比显著上升。免疫组织化学检测结果显示,RIP3蛋白主要分布在小鼠肺泡壁上皮细胞以及肺动脉血管内皮细胞,呈弱阳性表达,而攻毒组RIP3蛋白在气管粘膜下层细胞也有中至强阳性表达;Slit2蛋白在对照组和rVK627E组小鼠的肺泡上皮细胞以及气管粘膜上皮细胞中呈现中强阳性表达,而在VK627组中呈现弱阳性表达。Robo4蛋白的分布和表达情况与Slit2蛋白相似。综上所述,H9N2 AIVs感染小鼠后,会显著影响RIP3和Slit2/Robo4的表达和分布,且其表达和分布与H9N2 AIVs对小鼠的致病性密切相关;PB2蛋白627位点的突变在H9N2 AIVs影响RIP3、Slit2和Robo4表达和分布中起着重要作用。该研究结果将为进一步探究H9N2 AIVs及其点突变毒株介导宿主病理发生的分子机制和抗炎策略的选择提供基础数据。

Slit2在小鼠银屑病样皮炎模型炎性浸润中的作用

目的观察分泌型糖蛋白Slit2在咪喹莫特诱导的小鼠银屑病样皮炎模型中的表达及作用。方法采用免疫荧光观察咪喹莫特诱导的小鼠银屑病样皮损中Slit2的定位,PCR及Western blot检测皮损中Slit2的表达。30只小鼠随机分为5组:正常组、IMQ模型组、Slit2 siRNA组、Slit2蛋白低剂量组(100 ng/ml)、Slit2蛋白高剂量组(300 ng/ml),每组6只小鼠。每天对小鼠皮肤进行PASI评分,HE染色测量表皮厚度,计数各组真皮内炎症细胞数及血管密度,RT-PCR检测各组皮损处IL-23、IL-17A、IL-22 mRNA表达量,免疫组化检测各组皮损处Ki67表达及CD3 T细胞数量。结果咪喹莫特诱导的小鼠银屑病样皮炎模型皮损处Slit2的表达升高。相较于模型组,Slit2 siRNA处理后PASI评分增加,表皮变厚、表皮细胞增殖程度增加,真皮炎性细胞浸润增多及血管密度升高,IL-23、IL-17A、IL-22 mRNA水平升高,CD3 T细胞数量明显增加。给予重组Slit2蛋白处理后,PASI评分降低,表皮变薄,表皮细胞增殖程度降低,真皮炎性细胞浸润及血管密度降低,IL-23、IL-17A、IL-22 mRNA水平降低,CD3 T细胞浸润明显减少。结论Slit2在咪喹莫特诱导的小鼠银屑病样皮损中表达升高,使用Slit2 siRNA抑制皮损处Slit2表达可加重皮炎程度,在皮损处使用重组Slit2蛋白处理可减轻皮炎程度,Slit2对咪喹莫特诱导的小鼠银屑病样皮炎具一定的抗炎作用。

高能激光光束质量β因子测量方法

高能激光光束质量β因子测量装置主要用于强激光系统状态调试和综合性能参数诊断,用于评价激光系统出光性能以及远场光斑可聚焦的能力。针对接近衍射极限光束质量β因子测量过程中被测光斑在面阵相机上所占的像素点太少等缺陷,研究了采用聚焦显微放大与高精度扫描狭缝相结合的光束质量β因子测量方法,并对相关方案进行了分析计算。此外还设计了采用固定像差元件及平行光管光源组合的激光光束质量β因子测量结果验证方案,对研制的高能激光光束质量β因子测量装置进行了不确定度分析,测量不确定度优于10%。

裂隙灯显微镜下结膜囊肿取出术的疗效

目的明确门诊行裂隙灯显微镜下结膜囊肿取出术治疗结膜囊肿的疗效和安全性。方法在门诊病历系统收集2018年3月至2020年3月在中山大学中山眼科中心门诊行裂隙灯显微镜下结膜囊肿取出术共56例57眼结膜囊肿患者。手术过程:术前结膜囊清洁,丙美卡因表面麻醉后,由高年资眼科专科护士在裂隙灯下采用负压抽吸囊肿,完整吸出囊膜,术毕涂抗生素眼药膏。术后随访观察眼表疾病指数(OSDI评分)、复发情况、并发症和患者就医体验。结果56例患者行裂隙灯显微镜下结膜囊肿取出术的手术成功率为100%,患者未出现并发症。患者术后28 d OSDI评分较术前降低,差异有统计学意义(P<0.001),患者就医体验良好,随访1个月、6个月、2年,回访无复发。结论门诊行裂隙灯显微镜下结膜囊肿取出术方便快速,创伤小,术后伤口愈合良好,具有安全性、可行性和有效性,效果好,患者就医体验良好。

螺旋缝隙泄漏双向流固耦合方法

针对螺杆泵泄漏机理,利用数值模拟加数据拟合方法,提出了一种针对螺杆泵螺旋微小缝隙泄漏的双向流固耦合模拟方法.利用此方法,对比了单向流固耦合和双向流固耦合方法在螺杆泵泄漏计算结果的偏差,计算结果表明,间隙越小偏差越大,间隙为0.500 mm时两结果相差20.3%,说明螺杆泵这种刚柔配合螺旋缝隙泄漏必须利用双向流固耦合求解才能获得准确结果.随后利用双向流固耦合方法对三维螺杆泵模型进行有限元分析求解,研究了初始间隙、流体介质黏度、螺杆泵单级腔室压差、进出口压力对螺杆泵泄漏的影响.结果显示:泄漏量随初始间隙的增大而增大,随流体介质黏度的增大而减少;进出口压力变化对螺杆泵泄漏影响很小,可以忽略;腔室间的压差造成橡胶定子变形形成间隙,间隙随着压差增大呈线性增大.最后利用双向流固耦合方法计算了不同举升压力螺杆泵的容积效率,与试验结果对比误差在±5%以内.

基于气动位移传感器的纵切车床热误差测量方法研究

针对传统纵切车床热误差测量方法时间长,导致测量过程中的瞬态热行为影响测量结果的问题,提出了一种基于气动位移传感器的纵切车床热误差测量方法。首先,将两个气动差动变压器(Linear Variable Displacement Transducer,LVDT)式位移传感器安装于刀具架上;其次,利用数控程序控制测量,可以实现刀具运动空间内X和Y方向热误差的测量,测量时间缩短至5 s;最后,进行热误差测量实验。实验表明:这种方法的测量结果与激光干涉仪测量结果平均偏差小于0.5μm,验证了这种方法的可行性与有效性。这种方法测量时间短、成本低,为纵切车床热误差补偿提供了依据。

纵切自动车床环境温度变化误差试验研究

为研究环境温度变化对纵切自动车床热误差的影响,本文以RTS20瑞士型纵切自动车床为试验载体,通过环境温度变化误差(ETVE)试验装置,开展了恒主轴转速(5000 rpm)变环境温度、变主轴转速(0~8000 rpm)变环境温度的热误差试验,对环境温度对热误差的影响进行了研究分析。结果表明:在相同主轴转速下,环境温度变化影响着车床结构各部位的温升,进而影响热误差;在随机主轴转速下,主轴轴承等温度测点的温升受转速变化的影响,热误差的增长与关键测点温度具有相同变化周期,但不具有相同变化趋势,即温度快速升高时热误差并不一定也正向增长;空调开启后各测点温度有明显降低,最高降幅可达3℃,热误差随之也有明显降低趋势,最高降幅达6μm。