日本对静态破碎剂的研究

采用静态破碎剂破碎岩石、素混凝土、钢筋混凝土,没有爆破冲击波和飞散物;除钻孔时产生噪音、振动外,没有其它噪音和振动。日本工程界日益重视这种破碎药剂。静态破碎剂在日本也叫作缓速破碎剂、膨胀性破碎剂、非爆破碎剂等。我国统称为静态破碎剂。     

两级多锥内通道圆锥破碎机

两级锥体内通道破碎机是在破碎腔中设置多个破碎内锥体，它包括动力装置，传动装置，破碎体，破碎采用静压力破碎原理，使物料在破碎腔内以静压力，小能量多次挤压破碎，利用离心力排料，具有过载保护和粒度调节功能。     

非规则外形内聚颗粒模型的构建及其破碎能分析

考虑矿石的非规则外形、内部不同组分及其之间的力学特性,基于离散元数值分析方法、离散元软件EDEM及其二次开发,构建一种多尺度非规则外形内聚颗粒模型;利用颗粒模型在剪切挤压破碎机中对矿石破碎过程的破碎能耗特性进行分析。结果表明,破碎能与剪切挤压破碎机的加载方式有密切关系,在内锥振动频率一定时,外锥的转速越快,破碎能越大;外锥转速一定时,内锥振动频率越高,破碎能越大;矿石破碎越多,破碎能越大;矿石破碎速度越大,破碎能增长越快;矿石破碎速度减少,破碎能随之减小。     

大破碎比颚式破碎机及对破碎工艺流程的变革

介绍了新型破碎设备--外动颚大破碎比颚式破碎机及该系列产品的技术参数、性能特点;可用一段大破碎比破碎机取代传统流程中的两段或三段破碎,新型破碎设备的研制成功带来了破碎工艺的变革。     

基于冲击实验的颗粒破碎模型微观参数分析

对矿石颗粒进行双摆锤冲击实验,考察在不同冲击角时矿石的破碎效果;结合数值模拟技术构建颗粒破碎模型,通过对颗粒破碎模型内部结合参数进行分析取值,仿真颗粒破碎模型在不同冲击角时的破碎情况,研究满足模型破碎效果与实际矿石破碎效果相一致的参数组合。结果表明:当冲击角不同时,矿石的破碎效果存在差异;当冲击角小于35°及大于35°时,模型破碎效果与实际矿石的相一致,进一步表明所构建的颗粒破碎模型与实际矿石在一定程度上具有相关性与统一性。     

废旧印刷线路板基板粗碎实验研究

为了解决废旧印刷线路板资源化利用过程中的粗碎问题,分析其破碎过程受力特点,提出选择差速破碎方法;根据线路板基板的特点,选择"以点代线"的方法对其断裂破碎进行模拟;利用Minitab软件设计破碎实验,根据实验结果进行因子分析,并结合二分法进行二次实验。结果表明:"以点代线"的模拟方法具有一定的可行性;差速破碎比等速破碎具有更高的破碎效率;Minitab软件在废旧印刷线路板基板破碎实验设计上具有一定的可靠性;确定差速破碎参数为差速50 Hz-25 Hz,破碎效率可达90.4%。     

静力破碎剂的破坏条件式

1 静力破碎剂破碎物体的特点静力破碎剂不属于危险物品,破碎物体时不会产生飞石,震动和有害气体,在各种工程实践中正逐步得到推广应用。静力破碎剂是利用在约束条件下 CaO 水合反应和 Ca(oH)_2结晶发育所形成的膨胀压来破碎物体的。静力破碎剂的膨胀压使物体在钻孔周边产生径向压缩变形,同时钻孔在切向上     

炸药爆炸作用对煤基固废中煤矸石的破碎研究

为了满足快速破碎煤基固废中大量大颗粒煤矸石的要求,利用炸药爆炸破碎方式,设计了敞口与近似密闭条件下的破碎装置,从理论与实验方面分别进行了炸药爆炸作用对煤基固废中煤矸石的破碎研究。结果表明,采用炸药爆炸产生的冲击波对煤基固废中大颗粒煤矸石进行破碎时,由于冲击波反射破坏作用,煤矸石的破碎过程起始于外部层裂或崩落。此外,与敞口体系相比,近似密闭条件可有效提升煤矸石的破碎效果。若进一步扩大破碎装置中的煤矸石装填量,增加破碎所需的爆破药剂用量,有望大幅提升煤矸石的快速破碎能力。     

双腔颚式破碎机动态破碎力分析

为提高双腔颚式破碎机破碎力计算的准确性,使用速度瞬心法,分析双腔颚式破碎机偏心轴旋转360°动颚的运动规律及破碎腔的变化规律,提出有效破碎腔折算系数,并对破碎力的变化规律进行分析.结果表明,破碎力随有效破碎腔的变化呈周期性变化,修正了最大破碎力计算公式,得出双腔颚式破碎机在偏心轴转至（水平向右逆时针转起）170°时左腔破碎力达到最大值,转至350°时右腔破碎力达到最大值.对完善双腔颚式破碎机的基础理论有重要意义.     

用静力破碎剂破碎岩石时控制岩石断裂面方向研究

前言岩巷掘进或混凝土建筑物等进行破碎或拆除,由于振动及噪音的限制,常常不能使用炸药。静力破碎剂就是在这种条件下研制出来的新型破碎材料,它的施工实例近年有许多报告。然面,炮眼充填静力破碎剂后,被破碎物体由于需经很长时间才开始破碎,     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.