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Heat treatment, in view of later knowledge, is seen to have other effects than to destroy or lower the vitality of micro‐organisms initially present; there are the more obvious changes of flavour and of consistency brought about by the partial cooking, but there are also the possible lowering of the vitamin potency and the still more subtle changes in the salts which may, after heat treatment, be rendered less available than in the raw product. The importance of these considerations cannot be too much stressed when it is remembered that heat treatment is, generally speaking, an inherent stage in the process of canning. It is the heat treatment which preserves the goods, the sealing of the can being merely a means of prevent re‐contamination. The chemist, no less than the physiologist, has been much concerned with the changes in foods caused by heat treatment as a method of preservation, and, as a result of his investigation, there is now a better understanding of the changes which take place, with a consequent improvement in the methods of processing. For a number of years, however, this country, in common with many others, has relied, in so far as its supplies of meat are concerned, on products preserved by “cold,” and the freezing of beef, the chilling of mutton, have made available to us the cattle of the Argentine and the sheep of New Zealand. Initially the processes employed were crude, the post‐mortem changes were imperfectly understood, conditions of storage, before, during and after shipment, were haphazard, and the methods of defrosting far from scientific. How far the methods have advanced, and to what extent the scientist has been concerned in the elucidation of the many problems, will be realised from the reports of the Food Investigation Board. It is not suggested that all the advance is due to the work of the Low Temperature Station a Cambridge—much has been done in other countries‐but the investigations carried out by the scientists a this station have been fundamental. Food producers in America were the first to realise the importance of the latest development in freezing, the advent of the “ Quick Freezing Processes ” marking a distinct advance in technique. When cellular tissue is normally frozen and subsequently defrosted, rupture of the cells may have occurred and the structure of the substance consequently partially broken down. When, however, the tissue is quickly brought down to a very low temperature, it is found that in many cases this breakdown in tissue does not take place. These principles have been applied to commercial installations, and fish, meat, fruit and vegetables so treated show on defrosting remarkably little change in character. Preservation by desiccation is a method employed for certain materials with great success. Sun‐drying of fruits (sultanas and dates, to quote but two) and the sun‐drying of cereal products such as macaroni is still practised. An important industry concerned with the drying of milk has developed in most milk‐producing countries, whilst dried eggs and dried egg‐albumin form important items of commerce. It is obvious that the object of concentrating such substances as fruit juices, milk and vegetables and animal liquid extracts is ideally to reduce the water content and obtain a product which, when the water is ultimately restored, gives a solution or material having the original taste, aroma and food value. The effect of heat is often, however, to change these characteristics, and although by the use of a vacuum the temperature to which the substance is submitted is lowered, changes still take place, and much of the aroma depending on volatile constituents is lost. To a very great extent this has been overcome by a method of desiccation which is essentially partial freezing, a method which has not yet received much publicity as it has only lately emerged from the experimental stage. The practical application of this principle is due to Dr. G. A. Krause, of Munich, who has invented and designed a dual process of concentration. In this process the liquid is first concentrated by freezing out water as ice, which is removed by mechanical separation in a centrifuge. By ingenious mechanical and regenerative devices this process has been made extremely efficient, the losses being only 1–2 per cent. of the original juice, although the efficiency is not maintained when the solids‐content of the product has been raised to 40–50 per cent. This liquid is then further concentrated by evaporation at a low temperature, about 10°–15° C. The differential evaporation of water as compared with the aromatic flavour constituents occurs because the removal of water as vapour at this temperature depends solely on the rate of diffusion of the molecules into the gas space. As water has a small molecule compared with the large molecules of the esters, ethers and alcohols of the flavouring substances, it escapes more readily ; the conditions of evaporation as given in the patent are all designed to aid this escape. A reduction in pressure may be used to speed up the process without interfering with the differential diffusion, and the provision of an atmosphere of small molecules (e.g., hydrogen) also has the same effect. A large surface for the evaporation is made by spreading the liquid as a thin continuously renewed film. The condenser is situated very near the evaporating liquid to remove the water molecules quickly (a distance of 3 cm. is the maximum diffusion path). The atmosphere may be circulated or disturbed to hasten the diffusion and, most ingenious of all, it may be blown towards the evaporating liquid when, if a velocity is used just greater than that of the heavy molecules leaving a liquid surface, the loss of flavour may be entirely eliminated while the rate of water evaporation is only reduced by 10 per cent. By these means a concentrate containing as much as 65 per cent. solids and capable of storage without deterioration at ordinary temperatures may be prepared, and 80 per cent. of the original vitamins retained. The use of refrigeration in the preservation of food has necessitated the use of refrigerated transport to complete the links between producer, manufacturer, retailer and customer. The variety of commodities and the different conditions they need create varying demands on the methods of insulating and refrigerating transport vehicles. The British railways have 4,000 refrigerated railway vans, and such vans, containing perishable produce, came regularly to England from Austria and Italy by way of the train ferries. These vans are designed for fairly high temperatures, 35–40° F., and long hauls, and use ice as a refrigerant. At the other end of the scale is the road vehicle, which may have a temperature as low as 0° F., but is only on its journey about 12 hours. It is in these road vehicles that the greatest advances have been made, for conditions in England do not justify the railways in expenditure on elaborate equipment. The early road vehicles were insulated boxes on a lorry chassis and were refrigerated by ice and salt, which was “messy” and caused bad corrosion of the chassis. The introduction of an eutectic solution, virtually a mixture of a freezing salt and water in a definite proportion, which was frozen as a whole in a sealed tank, was made some few years ago. This removed the “messiness,” conserved the salt and produced greater efficiency and a more stable temperature.
A NEW aircraft instrument has been produced by Mr. Pollock Brown which, it is claimed, combines the functions of turn indicator and fore‐and‐aft level. The details of the…
A NEW aircraft instrument has been produced by Mr. Pollock Brown which, it is claimed, combines the functions of turn indicator and fore‐and‐aft level. The details of the “P.B. Deviator,” as the device is called, can bo seen in the accompanying drawing.
The purpose of this paper is to empirically examine the value of Masters of Business Administration (MBA) degree. The authors aim to bridge the gap between the theory and…
The purpose of this paper is to empirically examine the value of Masters of Business Administration (MBA) degree. The authors aim to bridge the gap between the theory and individual understanding of the value of an MBA program.
This empirical paper used a non-experimental design to test a proposed model based on a review of relevant literature. MBA alumni completed surveys capturing the constructs researched.
The findings of this research suggest that an MBA adds value to both MBA alumni as well as the organizations who hire them. The main source of this value is the knowledge and skills acquired while taking academic courses in the MBA program.
The implication of this research is that an MBA does add value to students that is not necessarily obtained through work experience alone.
The MBA degree qualifies an individual to manage an organization. An MBA does provide high potential for return on investment to both individuals well as the organization who hires them.
Economic growth requires entrepreneurs, professionals, business specialists, and managers. The research findings provide evidence that MBA program graduates do make a significant contribution toward improving the organization employing them. These profitable organizations in turn invest back in the community they operate in and help to improve the overall socio-economic fabric of the local economy. The results of this study also suggest that investment in MBA programs by local governments could bring back significant returns to the community in terms of job growth and availability of quality workforce.
Although a considerable amount has been written about the value of an MBA education, there is still a lack of research in the area linking human capital with organizational performance for MBA graduates. This contribution is also of special importance amid the recent criticism of the MBA by prominent management scholars.
Wholesaling is a brutal business. Only 20 percent of all wholesale distributors managed to beat the S&P 500 over the last five years, while more than 50 percent…
Wholesaling is a brutal business. Only 20 percent of all wholesale distributors managed to beat the S&P 500 over the last five years, while more than 50 percent consistently destroyed shareholder value. To understand what drove a 1,000 percent difference in returns between the best and worst distribution performer, the author interviewed the managers of firms that have consistently out performed the market. One counterintuitive insight ‐ distribution must focus on local business. Local, not national, market share drives profitability. The interviewers also learned the ingenious tactics the most successful companies have adopted to capture higher gross margins than their competitors, and how these leading companies have reduced operating expenses. The best distributors share a three‐legged strategy: they focus investments to gain local market share, they select their service offering carefully to pump up gross margins and they slice operating expenses to the bone.
YOU have asked me to address you on the subject of The Public Library Service of To‐day and the Carnegie Trust Policy in relation thereto. The subject of libraries is…
YOU have asked me to address you on the subject of The Public Library Service of To‐day and the Carnegie Trust Policy in relation thereto. The subject of libraries is large and important, but it is one which people refrain from studying because they are apt to think of a library as a room containing a collection of rather musty old books, and we have to dismiss that idea from our minds before we can actually appreciate what a library is, and what the library service means. I find that in 1692 a work was published under the title of “The Compleat Library or News for the Ingenious, containing several Original Pieces, Notes on Memorable Passages Happening in May, as also the State of Learning in the World, to be Published Monthly.” That was a description in the year 1692.
How often, I wonder, does the reader look up from his favourite newspaper to consider how it is done? Those ingenious comparisons, the revealing statistics, the background to the news, published at high speed and, on the whole, accurately, how are they arrived at?
FOR many years it has been appreciated that the ejector scat does not provide a complete answer to the problem of escape from aircraft flying at supersonic speeds. Many…
FOR many years it has been appreciated that the ejector scat does not provide a complete answer to the problem of escape from aircraft flying at supersonic speeds. Many ingenious escape devices have been suggested which will protect the pilot or aircrew member during the critical periods of deceleration and descent and most of them have involved the use of a capsule enclosure.
A PREVIOUS paper by Mansfield considered the problem of the torsion of a doubly symmetrical rectangular box containing a large number of equidistant identical webs…
A PREVIOUS paper by Mansfield considered the problem of the torsion of a doubly symmetrical rectangular box containing a large number of equidistant identical webs. Mansfield overcame the practical difficulty involved in solving the large number of simultaneous equations by an ingenious approximate method consisting of the replacement of the webs by an equivalent continuous medium. This device resulted in the derivation of a simple differential equation instead of the system of simultaneous equations.
THE old and time‐tried chemical methods of determination of the technological properties of materials have, during the last 15 or 20 years, been accompanied and perfected…
THE old and time‐tried chemical methods of determination of the technological properties of materials have, during the last 15 or 20 years, been accompanied and perfected by physical methods, such as the X‐ray or Gamma‐ray methods (i.e. the so‐called macroscopic and microscopic methods of material testing). These new methods have been developed to such an extent that the modern manufacture of sensitive and complicated apparatuses, such as aeroplanes, seems practically impossible without these ingenious methods of “ physical analysis.” The microscopic methods of determination particularly have been developed to a high degree of perfection, due to an equally rapid development of microscopic apparatus and auxiliary materials which had become necessary when from being an exclusively scientific apparatus the microscope was transplanted into the industrial laboratories. Microscopic testing of materials in vertical and oblique illumination is an absolutely indispensable aid of all industrial laboratories of to‐day.
IN the articles on the VB‐10 tandem‐engined single‐seater and the Arsenal de l'Aéronautique the Vernisse coupling has been mentioned. The desirability of a constant‐torque…
IN the articles on the VB‐10 tandem‐engined single‐seater and the Arsenal de l'Aéronautique the Vernisse coupling has been mentioned. The desirability of a constant‐torque coupling was realized as long ago as 1937 and work was begun on the design in 1939. The idea was to develop a coupling primarily to enable engines to be mounted in tandem so that they would drive co‐axial airscrews, but also to provide a shaft joint that would take up structural deflexions for extension drives of single engines.