The application and programming of an image store for the SEM

The programming and use of a purposebuilt digital image store constructed for a SEM is described. The system is based on purpose designed circuitry controlled by a Motorola MC68000 and is capable of noise-averaging using multiple frames, colour look-up tables, high-resolution photographic recording, image processing using matrix functions, some image quantification, and x-ray spectrum acquisition. The way in which the FORTH language provided an efficient means of controlling the SEM is described and examples of each type of operation are presented.     

Assessing the environmental performance of stabilised rammed earth walls using a climatic simulation chamber

The SHU climatic simulation chamber is a novel piece of apparatus that allows testing of full-sized walls with realistic inner and outer wall climatic conditions. Four SRE test walls were successfully constructed and tested over four separate regimes to measure physical properties such as pressure-driven moisture ingress, rate of moisture penetration, and internal/interstitial condensation. The walls far exceeded a series of cyclic pressure-driven rainfall penetration tests based on BS 4315-2. After 5 days of exposure to static pressure-driven moisture ingress there was no evidence of moisture penetration or erosion. The embedded sensor array detected no significant increase in the relative humidity or liquid moisture content inside the test walls, throughout a range of temperature differentials with high levels of humidity, indicating a negligible risk of internal or interstitial condensation.     

福建省革命历史纪念馆预应力结构布置和设计

本文介绍福建省革命历史纪念馆的预应力结构布置及其结构布置及其结构设计．为了节省层高和解决顶层边柱大偏心受力，柱纵盘过多问题，采用了在两榀向框架之间加设一道16～18～16m的预应力混凝土连续梁。并讨论了在结构抗裂制验算中是否考虑水平荷载效应的问题。     

High-resolution short range ion detectors based on 4H-SiC films

The energy resolution of SiC detectors has been studied in application to the spectrometry of α particles with 5.1–5.5 MeV energies. The Schottky barrier structure of the detector was based on a CVD-grown epitaxial n-4H-SiC film with a thickness of 26 μm and an uncompensated donor concentration of (1–2)×10¹⁵ cm^?3. An energy resolution of 0.5% achieved for the first time with SiC detectors allows fine structure of the α particle spectrum to be revealed. The average energy of the electron-hole pair formation in 4H-SiC is estimated at 7.71 eV.     

Preparation of gossypol from cottonseed pigment glands

Summary Cottonseed pigment glands, produced from whole cottonseed meal and defatted cottonseed meal by the gland flotation process, have been investigated as a raw material for the production of gossypol. Methods based on the previously reported properties of gossypol and cottonseed pigment glands have been developed for the relatively rapid isolation of gossypol from pigment glands. Extraction of gossypol from pigment glands with acetone followed by precipitation of gossypol acetic acid from the extract was found to be the preferable method for obtaining pure gossypol in good yields. The precautions which must be applied in order to produce gossypol on a large scale by the acetone-acetic acid method are discussed together with methods for the purification and preservation of gossypol. Presented at the Fall Meeting of the American Oil Chemsits' Society, October 20–22, 1947. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

Melamine-formaldehyde-NTA chelating gel resin: Synthesis, characterization and application for copper(II) ion removal from synthetic wastewater

A new chelating resin was synthesised by anchoring nitrilotriacetic acid (NTA) to melamine during the melamine-formaldehyde gelling reaction in the presence of water, using acetone and guaiacol as a porogen mixture. This technique gives a porous chelating gel resin capable of removing heavy metals from wastewater. FT-IR, XRD, elemental analysis, surface area and water regain measurements were conducted for characterization of the new chelating gel resin. A comprehensive adsorption study (kinetics isotherm, and thermodynamics) of Cu(II) removal from synthetic acidic aqueous solutions by adsorption on this resin was conducted regarding the effects of time, temperature, initial pH and copper(II) initial concentration.     

A comparison of the corrosion behavior of WC-Co-Cr and WC-Co HVOF thermally sprayed coatings by in situ atomic force microscopy (AFM)

The corrosion behavior of WC-Co-Cr and WC-Co high velocity oxygen fuel (HVOF) sprayed coatings were examined in static saline conditions. Direct current (DC) polarization tests were conducted and the electrochemical corrosion behavior was shown, by in situ atomic force microscopy (AFM) and scanning electron microscopy (SEM), to be complex because of the composite ceramic-metal nature of the coating. The addition of chromium to the matrix greatly enhanced the corrosion resistance of the coating.     

Co‐Extrusion of Multilayer Glass Fiber‐Optic Preforms: Prediction of Layer Dimensions in the Extrudate

A three‐dimensional, incompressible and noncavitating model of a glass‐stack coextrusion process, under isothermal and non‐isothermal conditions is numerically simulated by means of computational fluid dynamics. A dynamic mesh approach is taken in a domain‐subdomain type setup to simulate the transient steps in the steady‐velocity phase of the experimental co‐extrusion. The multiphase setup consists of a glass‐stack which is composed of different glass compositions. Experimentally measured glass properties, such as the temperature coefficient of the viscosity of the supercooled glass melts are used to define the flow behavior of the glasses in the starting stack when extruded. The modeled extrudate is numerically verified for transient and spatial errors, leading to the choice of a suitable mesh. Excellent agreement is found between modeling and experiment when plotting the core/cladding dimensions of a step‐index extruded fiber‐optic preform along the length of the preform. This approach can identify the stable part of the preform, in terms of constant core/cladding layer geometry, obviating costly and time‐consuming experimental iteration. Also, the modeling allows prediction of the starting glass‐stack dimensions for a specified fiber design.