Effect of temperature on the absorption loss of chalcogenide glass fibers

The change in the absorption loss of IR-transmitting chalcogenide glass fibers in the temperature range of -90 degrees C /= 6 mum the change in loss was mainly due to multiphonon absorption. The change in loss for tellurium-based glass fibers increased significantly at T = 60 degrees C. The increase in the loss at short wavelengths (lambda /= 9 mum, multiphonon absorption dominated the loss spectrum.     

THE USE OF PESTICIDES IN MALTINGS,BREWERIES AND DISTILLERIES APRIL 1974 - MARCH 1975

A survey of the use of pesticides in maltings, breweries and distilleries during the period April 1974 to March 1975 was made by the Pesticides Survey Group at the Ministry of Agriculture's Pest Infestation Control Laboratory at Slough in collaboration with the Department of Agriculture and Fisheries for Scotland. A breakdown of the insecticides and rodenticides used, including quantities and numbers of users, is given. The results show that in most cases, the official recommended measures to control pests are being followed.     

孩子的天然学堂

在澳大利亚,伴随着妇女就业和单亲家庭的增长,多数家庭和儿童都非常依赖于儿童看护服务,比如,社区幼儿园、幼儿中心、临时家     

England's Town Development Act: 1952: PART I: Background of the Act

The land use model recasts an unsuccessful urban form of the past. Concentric rings of declining land value begin at the intense, historic center and grade down through concentric rings to become the city plan. Little planning remains after such a model is accepted. The new freedom of the auto-age city is lost to the principle of a falling body. Further, the land use model plan restricts mobility of resident and employer by type, each to his ring Urban land value patterns are sustained by public action or inaction. A true city plan musters this power to form the best possible city.     

Developing eco-friendly methods for purification of compounds derived from hydrogenated cardanol

The present work made a comparative study between two purification methods, column chromatography and recrystallization, for compounds derived from cardanol, a by-product of the cashew industry (Anacardium occidentale L.). The compounds were successfully synthesized and characterized, focusing our attention to results obtained in terms of yield, purity, generation of solid waste and amount of solvent used in each purification process. For all the synthesized compounds, the amount of solvent used was greatly reduced in the recrystallization process, with purities above 80%, when compared to chromatographic column, which still demands high amounts of eluent.     

Molecular Weight Patterns of Nägeli Amylodextrins

This research was designed to assess the utility of a four-column high performance size-exclusion chromatography (HPSEC) system to characterize starch-based carbohydrates of different sizes. Corn starches with varying amounts of amylose were treated with 16% sulfuric acid to create Nägeli amylodextrins. During treatment, sub-samples were taken at various intervals from 0–100 days. The washed, dried sub-samples were chromatographically analyzed using four Shodex lonpak columns linked in series. Chromatograms showed the progressive depolymerization of starch. Pullulan molecular weight standards were used to estimate amylodextrin molecular weights (MW). Number-average MWs of amylodextrins decreased as the original starches' amylopectin content decreased. A single HPSEC system can be effectively used to characterize carbohydrates ranging in size from starch to amylodextrins; and to monitor the acid (or enzyme) depolymerization of starches.     

Fractionation of Starch Amylopectin and Amylose by High Performance Gel Filtration Chromatography

A gel filtration chromatographic method has been developed which is capable of fractionating amylose and amylopectin in starch. Three GFC columns (2 × 4000 A and 1 × 300A PL Separation Sciences, Polymer Laboratories Ltd,) are used in series using sodium chloride solution as eluent. Minimal sample preparation is involved which includes a preliminary wetting of powder starch with ethanol followed by dissolution with sodium hydroxide. Since the solvent system is aqueous, cooked starch samples are analysed by direct dissolution with sodium hydroxide. The method shows promise as a rapid technique in elucidating starch structure.     

Mechanical property enhancement in short-fiber composites through the control of fiber orientation during fabrication

The mechanical properties of plastics and elastomers reinforced by short fibers are generally dictated by the selection of matrix and reinforcement. However, the high tensile properties attainable in these systems through laboratory processing techniques are frequently not obtained in conventional fabrication operations. To gain a wider latitude in meeting economic and performance constraints, the control of composite structure in the fabrication step should not be overlooked. Tool geometry and processing conditions can be manipulated specifically to control the fiber orientation distribution in the product. A study of fiber orientation in composite compounds during flow through runners, gates, and dies leads to recommendations for optimizing the directional strength and stiffness according to a kinematic model. Performance data on parts fabricated from various short-fiber composite materials bear out these projections.     

The extrusion and performance of plasticized poly(vinyl chloride) hose reinforced with short cellulose fibers

Short fibers of natural cellulose treated to provide dispersability and strong interfacial bonding are ideal reinforcements for plasticized vinyl compounds. The development of substantial strength and stiffness in unidirectional composites indicates the reinforcing potential of these high aspect-ratio fibers in soft compositions. Special extrusion dies developed to control fiber directionality in rubber extrudates are equally applicable to vinyl hose. The unusual expanding geometry of these tools aligns the fibers toward the circumferential direction to provide optimum reinforcement against contained pressure loading. Thus, reinforced poly(vinyl chloride) air and water hoses can be produced in a single extrusion step, since all of the necessary reinforcement is contained in the compound.     

Towards an end-to-end airborne remote-sensing system for post-hazard assessment of damage to hyper-critical infrastructure: research progress and needs

The objective of this article is to synthesize research findings and requirements pertaining to development of time-sensitive remote-sensing systems (TSRSS) that support decision-making pertaining to post-hazard assessment of damage to what we define as hyper-critical infrastructure (HCI), based on an aerial imaging approach known as repeat station imaging (RSI). The following TSRSS components are addressed and related findings are reported: (1) understanding information requirements of emergency managers pertaining to damage of HCI; (2) flight planning and data capture requirements for supporting bi-temporal RSI pairs; (3) automatic image registration and shadow classification and normalization routines applied to RSI pairs; (4) damage detection and delineation approach that exploits simple temporal differences in image brightness to automatically, reliably, and robustly delineates new cracks associated with damage; and (5) rapid data and information transfer to emergency managers. The highest priority follow-on research topics are: (1) integrating small unmanned aerial systems (sUAS) with the RSI approach, while enabling multiple view perspectives other than vertical (i.e. nadir pointing) and (2) developing and testing of machine learning routines for automatic identification of damage features from RSI pairs, particularly those captured from integrated sUAS–RSI.