A STANDARD UNIT OF DIMENSION FOR MASONRY1

Construction problems due to lack of coördination in sizes of different masonry materials are pointed out. It is proposed that these difficulties can be overcome by adoption of a standard “unit” of dimension to be used by architects and engineers in dimensioning building plans, and by masonry material manufacturers in determining the size of their products. No definite “unit” of measure is suggested, except that it should approximate one brick length plus one mortar joint, two brick widths plus two joints, or three brick thicknesses plus three joints. The application of the “unit” plan is given for face brick, common brick, paving block, fire brick, cement block, structural clay tile, terra cotta, cut stone, and to masonry openings for windows and doors. Illustrated with 74 photographs of masonry and 2 plates.     

DIMENSIONAL COORDINATION *

A method is described that has been developed by American Standards Association Project A62 for coordinating standard sizes of building products and for correlating the layout and design of buildings. Applications of the method to masonry and windows are discussed and layouts are shown.     

METHODS USED IN TESTING MASONRY SPECIMENS FOR BENDING,TENSION, AND SHEAR1

Twenty-four walls, 41/2 feet wide, 51/2 feet high, some 8 inches and some 12 inches thick, werr tested for bending alter aging sixty days and six months, respactively. It was shown that aging of lime mortar is essential. Failures in shearing stress were also due to immature mortar. Brick masonry withstands earthquake shocks when mortar is matured by aging. An outline of the more extensive tests is given.     

Aufbaukörnungen aus gipshaltigem Mauerwerkbruch – Teil 2: Untersuchungen im Pilotmaßstab

Heterogeneous construction waste such as masonry rubble has potential as a raw material for the production of lightweight aggregates similar to expanded clays or even pumice. In the present paper, the suitability of feedstocks with considerable gypsum contents was investigated in a pilot plant. Based on the results, initial technological statements could be made. According to these, energetic advantages can be expected in comparison with lightweight aggregates made from expanded clays.     

FCC原料加氢预处理生产超低硫汽油技术措施综述

阐述了超低硫汽油的生产对现有FCC原料加氢预处理技术的影响以及世界各国的技术策略,并指明了FCC原料加氢预处理技术在生产超低硫汽油中的发展方向和主要技术措施。研究表明:从生产30μg/g的清洁汽油到生产硫含量小于10μg/g的超低硫汽油会造成FCC原料加氢预处理装置氢耗高、运转周期短、加氢预处理-催化裂化联合装置经济性差等问题。FCC原料加氢预处理生产超低硫汽油的主要技术措施有:优化现有的FCC原料加氢预处理装置、对现有FCC原料加氢预处理装置增加一个反应器、增加现有FCC原料加氢预处理装置的进料量、开发FCC原料加氢预处理-FCC组合工艺、新建或改造成缓和加氢裂化装置、新建或改造成部分转化加氢裂化、新建或改造FCC汽油后处理装置。     

FRP布加固砌体结构界面粘结性能的研究进展

砌体结构存在着承载力低、抗震能力差等问题,所以对砌体结构的加固尤为重要。近些年在国内外兴起的纤维增强复合材料(简称FRP)以其轻质高强、耐久性好、施工方便等优点为砌体结构的加固提供了新的方向。FRP与砌体间的界面粘结性能是影响加固效果的关键因素之一。总结了国内外学者关于FRP加固砌体结构界面粘结性能的研究现状,通过收集到的试验数据对FRP加固砌体结构的极限承载力计算公式进行了校核,并对今后拟开展的研究工作提出了建议。     

Gas‐Liquid Direct‐Contact Evaporation: A Review

Gas‐liquid direct‐contact evaporators are characterized by the bubbling of a superheated gas through the solution to be concentrated. In other words, they are nonisothermal bubble columns. Despite their simplicity of construction, these units exhibit rather complex hydrodynamics and, similar to what occurs to isothermal bubble columns, the design of such units still poses a problem. The present paper reviews the literature regarding this kind of equipment, addressing both experimental studies and modeling efforts. The covered issues include classic and potential applications, bubbling regimes, gas holdup and bubble size distributions, as well as mathematical models proposed for simulating the unit. Additionally, pertinent literature on isothermal bubble columns is also discussed. Recommendations are made for future research.     

FIRING STRUCTURAL TILE1

The modern railroad-car tunnel kiln can fire structural tile economically in sufficient quantities for commercial operation. The setting arrangement is important both as to arrangement of flues and also as to the stability of the structure. Various sizes of tile can also be placed on the same car. There are approximately three tons of tile on each car. The kiln used is a Harrop car tunnel kiln, 350 feet long with a cross-section of 5 feet 8 inches by 5 feet 5 inches. Either oil or powdered coal is used as fuel. The tile are in the kiln a total of 29 hours, giving a total production of 130 tons per twenty-four hours.     

Heuristic evolutionary synthesis with non-sharp separators

If, in undertaking a process separation task, such as separating the constituent minerals of an ore to the most profitable extent, we allow limited separation in each process unit (as against requiring a “perfect split”), the number and connection of the units have to be found. Here it is done by building up the required flowsheet unit by unit, stopping when further addition does not increase the profit. Recycle of streams is allowed, the extent being controlled by an arbitrary parameter over which a search may be made.Simulation is sequential modular, with convergence and the necessary process optimization of each intermediate flowsheet carried out by infeasible path successive quadratic programming.As heuristics guide the construction, “good”, not necessarily “the best”, flowsheets are obtained, which may be further ranked, such as by controllability and/or process flexibility.The approach is here developed for “homogeneous” flowsheets (all process units identical), with minerals flotation separation as an example, using a very simple first-order kinetic flotation model. While countercurrent circuits are synthesized as limiting cases of the heuristics, flowsheets more profitable than these are also obtained. The paper reviews critically the heuristics and their application.     

双加压硝酸装置国产化问题探讨

分析了引进双加压硝酸装置及国产化硝酸装置中“四合一机组”和工艺系统存在的问题。提出相应的改进建议,使双加压硝酸装置的国产化工作不断完善。     

制氢装置的比较

从工艺流程、工程建设、生产运行和对环境影响等方面对以煤焦、焦炉气和甲醇为原料的制氢装置进行了比较.在设计规模相当的情况下,焦炉气制氢装置在投资、建设用地、建设周期、生产操作、生产成本等方面都具有明显的优势.     

GAS AS FUEL FOR VITREOUS ENAMELING1

The typical furnace described has a burning chamber four feet wide, ten feet long and thirty-four inches high, no muffle being necessary. The furnace is of the intermittent type. All the details of normal production are given together with a resume of the surprisingly low total cost per hour. A comparison of the average hourly production on 24- and 22-hour bases is given. Also several suggestions are made that will materially effect additional economies in the use of gas for vitreous enameling.     

Solution of problems involving systems of distillation columns

A convergence method (called the Θ-method) and calculational procedure have been developed which may be applied to any system of distillation units. The procedure makes use of the programs of the individual units without modification. This amounts to the use of the programs of the individual units as building blocks for the construction of the model for the system. Any number of independent feeds to any one of the distillation units may be specified, and any number of sidestreams may be either withdrawn from the system or fed to any other unit of the system.     

Ligand-bridged oligomeric and supramolecular arrays of the hexanuclear rhenium selenide clusters--exploratory synthesis, structural characterization, and property investigation

Transition metal clusters, by virtue of their well-defined structures and unique properties, present themselves as an attractive class of structural and functional building blocks for molecular and supramolecular construction. Summarized in this Account are highlights of our efforts utilizing face-capped octahedral [Re(6)(mu(3)-Se)(8)](2+) clusters as the fundamental building units to create a wide variety of preprogrammed architectures. These include molecular "Tinkertoys", featuring stereospecific cluster units bridged by multitopic ligands and extended arrays of clusters engineered via hydrogen bonding and secondary metal-ligand coordination.     

碳纤维布加固混凝土与砌体结构施工技术比较与分析

本文通过在混凝土基材与砌体基材上粘贴碳纤维布时，因基材种类、表面缺陷、强度等方面的差异，进行施工技术比较与分析．并通过实例对砌体结构粘贴碳纤维布的特殊施工工艺及其良好的控制效果做了介绍和分析。     

大开间约束砖砌体结构的抗震性能与设计方法

提出对大开间砖砌体结构采取在砖砌体中设置钢筋混凝土墙中柱和水平条带的加强措施。通过大比例模型试验 ,探讨其抗震性能 ;采用非线性有限元法对约束砌体横墙进行全过程分析 ,采用弹塑性时程分析法对原型结构进行地震反应分析 ;在此基础上提出了相应的设计建议和构造措施。试验与理论分析结果表明 ,在 7度区采用大开间约束砖砌体结构建造 7层住宅 ,可满足抗震设防要求。     

WATER-TIGHT TERRA COTTA MASONRY*

In spite of the lessened opportunity for moisture to pass the face of a terra cotta wall as compared with brick masonry, certain precautions should be observed to produce a water-tight wall, especially where the exposure is severe. The bearing of each of the important properties of masonry cements in regard to their application to terra cotta is pointed out and recommendations are made for suitable cementing materials. Suggestions are offered for the selection of sand and for securing uniformity and intimacy of mix. A joint width of to ¼ inch is recommended where the regularity Of the units permits. The joints should be shoved and given a tool finish at the proper stage of stiffening. The joints subjected to extra severe exposure should be packed with prehydrated mortar and properly tool-finished. Mortar may be aided to adhere to a glazed surface either by using prehydrated mortars or by first painting the surfaces with cement paint. For back-up, a hollow tile with webs vertical is recommended.     

开封空分膨胀机-精馏塔系统与法液空装置的对接技术

从工艺流程特点、工艺对接条件、装置安全技术、开封膨胀机和精馏塔系统与法液空装置性能对照、空分装置的考核结果与评价几个方面对国产开封膨胀机和精馏塔系统与法液空装置对接的技术攻关内容进行论述,并通过对实际运行的技术数据分析,说明对接技术成熟、安全可靠,具有节约资金、工期短、见效快的优点,经济效益显著     

Mathematical modeling for simultaneous design of plants and supply chain in the batch process industry

Most supply chain design models have focused on the integration problem, where links among nodes must be settled in order to allow an efficient operation of the whole system. At this level, all the problem elements are modeled like black boxes, and the optimal solution determines the nodes allocation and their capacity, and links among nodes. In this work, a new approach is proposed where decisions about plant design are simultaneously made with operational and planning decisions on the supply chain. Thus, tradeoffs between the plant structure and the network design are assessed. The model considers unit duplications and the allocation of storage tanks for plant design. Using different sets of discrete sizes for batch units and tanks, a mixed integer linear programming model (MILP) is attained. The proposed formulation is compared with other non-integrated approaches in order to illustrate the advantages of the presented simultaneous approach.     

Design and construction of 4 × 1440 t/day MSF plants at Brindisi's power station (Italy): Acid / antiscale additive treatment for 100°C top brine temperature.

This paper reports the main parameters of the project, made for ENEL (Italian Electrical Power Government Company), regarding the design and supply of four MSF desalination plants at Brindisi's Power Station.The evaporators will be operated with anti-scale additive but are designed both for sulphuric acid and polymer antiscale treatment to operate at 100°C max. as top brine temperature.The distillate production (60 t/h each unit) will be used as high pressure boiler water make-up, then the distillate, mixed with the condensate coming from each unit, is demineralized by mixed bed ion exchange resin system; for this purpose, three mixed bed units are supplied.The paper reports the main design data, characteristics and materials of the above units.