Investigation on milling force of thin-walled workpiece considering dynamic characteristics of workpiece

Journal of Mechanical Science and Technology - The idea of integral calculus is used in traditional milling force prediction methods. In the traditional method, the milling cutter is divided into...     

Structural,magnetic and magnetostrictive properties of Co1-xLixFe2O4 synthesized by cathode materials of spent Li-ion batteries

In this study, we investigated the effects of substituting Li⁺ for Co²⁺ at the B sites of the spinel lattice on the structural, magnetic and magnetostrictive properties of cobalt ferrites. The Li⁺ substituted cobalt ferrites, Co_1-xLi_xFe₂O₄, with x varying from 0 to 0.7 in 0.1 increments, were synthesized with a sol-gel auto-combustion method using the cathode materials of spent Li-ion batteries. X-ray diffraction analysis revealed that all the Co_1-xLi_xFe₂O₄ nanopowders had a single-phase spinel structure and the lattice parameters decreased with increasing Li⁺ content, which can be proved by slight shifts towards higher diffraction angle values of the (311) peak. Field emission scanning electron microscopy was used to observe the fractured inner surface of the sintered cylindrical rods and the increased porosity resulted in a decreased magnetostriction. The oxidation states of Co and Fe in the cobalt ferrite samples were examined by X-ray photoelectron spectroscopy. High resolution transmission electron microscopy micrographs showed that most particles were roughly spherical and with sizes of 25–35?nm. Li⁺ substitution had a strong effect on the saturation magnetization and coercivity, which were characterized with a vibrating sample magnetometer. The Curie temperature was reduced due to the decrease in magnetic cations and the weakening of the exchange interactions. The magnetostrictive properties were influenced by the incorporation of Li⁺ at the B sites of the spinel structure and correlated with the changes in porosity, magnetocrystalline anisotropy and the cation distribution.     

现代公共建筑餐饮废水处理工艺

概括介绍了现代公共建筑中餐饮废水的水质特点及处理要求,并结合公共建筑餐饮废水处理工艺的特殊性,对混凝法、生物法、电化学法等一些处理工艺及工程应用实例进行了综述.认为具备一体化、体积小、占地少、噪音低、处理效果好、运行管理方便等特点的新型餐饮废水处理技术将得到广泛的应用.     

制备环丙沙星的哌嗪化工艺

采用乙氧羰基哌嗪与环丙羧酸缩合的方法，制备了环丙沙星。同时应用正交设计实验，研究了原料配比、温度、时间及溶剂用量对反应收率的影响，在优化条件下收率可达88．0％。     

碳酸锂在水和NaCl-KCl溶液体系中溶解度的在线测定

碳酸锂溶解度在工业结晶生产中是十分重要的基础数据。采用浸入式红外探头和拉曼探头在线监测溶液体系中CO₃^2-和碳酸锂的特征峰峰强的变化,依据Lambert-Beer定律得出溶液体系中实时在线测定碳酸锂的溶解度。通过在线测定,测得碳酸锂在氯化钠-氯化钾溶液（c_NaCl=0.446 6 mol/L,c_KCl=0.015 8 mol/L）中的溶解度高于在水中的溶解度值。实验测试出的水中碳酸锂的溶解度数据还能与Van′t Hoff方程较好地关联,进一步测算碳酸锂在其他温度下水中的溶解度值。此外,该方法测定的碳酸锂在水中的溶解度数据比文献值中采用重量分析法测试出的溶解度数据偏小,是因为测试装置不同造成的。     

Effects of sulfate-reducing bacteria on the corrosion behavior of carbon steel

The influences of the growing process of sulfate-reducing bacteria (SRB) in seawater system on the medium state and corrosion behavior of carbon steel were studied by detecting solution state parameters and using corrosion electrochemical methods. The growing process of SRB in the seawater shows the three stages of growing, death and residual phases. The solution state parameters of the concentration of sulfide, the pH value and the redox potential changed during the three stages of the SRB growing process. And the corrosion rate of D36 carbon steel was accelerated during the growing phase and stable during the death and residual phases. The results indicate that the medium state and the corrosion rate of the steel do not depend on the number of active SRB, but depend on the accumulation of the metabolism products of SRB.     

微型橡胶同步带的研制

研制了一种微型橡胶同步带。强力层材料选用进口玻璃纤维线绳；包布层材料选用无锡产尼龙变形纱织物。带背和带齿胶料配合为：ＣＲ１００；氧化锌４；硬脂酸１；软化剂５；氧化镁５；防老剂３．５；炭黑５０；促进剂ＮＡ－２２，ＴＴ，ＤＭ适量。经检测和实际应用证明，成品带各项性能指标均超过本所企业标准和日本ＪＩＳＫ６３７９—８９标准，并达到国内同类产品的先进水平．     

南水北调中线总干渠水质变化趋势及污染源分析

为了解和掌握南水北调中线总干渠水质状况,依据总干渠26个常规水质断面监测数据,分析了总干渠沿程水质变化趋势。结果表明,主要污染指标(CODMn、氨氮、总氮和总磷)呈现出沿程增加趋势。根据影响总干渠水质的潜在影响因素,分析了7类污染源(直接水污染、大气粉尘沉降、桥面雨水污染、底泥污染、周边垃圾场淋溶液污染、雨洪污染、受污染地下水)及其可能对干渠水质产生的影响程度,并针对不同污染源提出了防控对策,供管理部门决策参考。     

一种新型无线粮仓害虫图像检测系统设计

提出基于分布式的无线图像传感器网络技术,利用无线数传模块之间的相互传递,将置于粮仓害虫收集器的CMOS摄像头采集得到害虫图像数据,通过无线的方式传输到控制室对粮仓害虫进行检测.采用了多频段技术及其他可靠的无线抗干扰措施,使系统稳定可靠,大大减轻了操作人员的劳动强度,实现低成本、无线、低功耗粮仓害虫检测.