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Modeling of material behavior by physically or microstructure-based models helps in understanding the relationships between its properties and microstructure. However, the majority of the numerical investigations on the prediction of the deformation behavior of AA2024 alloy are limited to the use of phenomenological or empirical constitutive models, which fail to take into account the actual microscopic-level mechanisms (i.e. crystallographic slip) causing plastic deformation. In order to achieve accurate predictions, the microstructure-based constitutive models involving the underlying physical deformation mechanisms are more reliable. Therefore, the aim of this work is to predict the mechanical response of AA2024-T3 alloy subjected to uniaxial tension at different strain rates, using a dislocation density-based crystal plasticity model in conjunction with computational homogenization.

A dislocation density-based crystal plasticity (CP) model along with computational homogenization is presented here for predicting the mechanical behavior of aluminium alloy AA2024-T3 under uniaxial tension at different strain rates. A representative volume element (RVE) containing 400 grains subjected to periodic boundary conditions has been used for simulations. The effect of mesh discretization on the mechanical response is investigated by considering different meshing resolutions for the RVE. Material parameters of the CP model have been calibrated by fitting the experimental data. Along with the CP model, Johnson–Cook (JC) model is also used for examining the stress-strain behavior of the alloy at various strain rates. Validation of the predictions of CP and JC models is done with the experimental results where the CP model has more accurately captured the deformation behavior of the aluminium alloy.

The CP model is able to predict the mechanical response of AA2024-T3 alloy over a wide range of strain rates with a single set of material parameters. Furthermore, it is observed that the inhomogeneity in stress-strain fields at the grain level is linked to both the orientation of the grains as well as their interactions with one another. The flow and hardening rule parameters influencing the stress-strain curve and capturing the strain rate dependency are also identified.

Computational homogenization-based CP modeling and simulation of deformation behavior of polycrystalline alloy AA2024-T3 alloy at various strain rates is not available in the literature. Therefore, the present computational homogenization-based CP model can be used for predicting the deformation behavior of AA2024-T3 alloy more accurately at both micro and macro scales, under different strain rates.

As yet there are no indications that the President of the Local Government Board intends to give the force of law to the recommendations submitted to him by the Departmental Committee appointed by the Board to inquire into the use of preservatives and colouring matters in food. It is earnestly to be hoped that at least some of the recommendations of the Committee will become law. It is in the highest degree objectionable that when a Committee of the kind has been appointed, and has carried out a long and difficult investigation, the recommendations which it finally makes should be treated with indifference and should not be acted upon. If effect should not be given to the views arrived at after the careful consideration given to the whole subject by the Committee, a very heavy responsibility would rest upon the Authorities, and it cannot but be admitted that the Committee ought never to have been appointed if it was not originally intended that its recommendations should be made legally effective. Every sensible person who takes the trouble to study the evidence and the report must come to the conclusion that the enforcement of the recommendations is urgently required upon health considerations alone, and must see that a long‐suffering public is entitled to receive rather more protection than the existing legal enactments can afford. To refrain from legalising the principal recommendations in the face of such evidence and of such a report would almost amount to criminal negligence and folly. We are well aware that the subject is not one that is easily “understanded of the people,” and that the complicated ignorance of various noisy persons who imagine that they have a right to hold opinions upon it is one of the stumbling blocks in the way of reform; but we believe that this ignorance is confined, in the main, to irresponsible individuals, and that the Government Authorities concerned are not going to provide the public with a painful exhibition of incapacity and inaction in connection with the matter. There is some satisfaction in knowing that although the recommendations have not yet passed into law, they can be used with powerful effect in any prosecutions for the offence of food‐drugging which the more enlightened Local Authorities may be willing to institute, since it can no longer be alleged that the question of preservatives is still “under the consideration” of the Departmental Committee, and since it cannot be contended that the recommendations made leave any room for doubt as to the Committee's conclusions.

In a volume of the Cornhill Magazine published in the year 1860 we have discovered an article entitled “Adulteration and its Remedy” which well deserves the attention of those persons who imagine that we have made “wonderful progress” during the past half century and that the trade morality of to‐day is infinitely superior to the trade morality of the past. The unknown author of this article must have had a very clear appreciation of the nature of the gigantic evil upon which he wrote and of the character and probable effectiveness of the remedies to be applied. The adulteration of the period is described by him as a “strange, disgusting and poisonous demon” and while it is true that at the time, as shown by the revelations of the “Lancet Sanitary Commission,” there existed many forms of gross, disgusting and poisonous adulteration which are but rarely detected nowadays, our author's somewhat hyperbolic definition may still be regarded as applicable. For many of the grosser forms of adulteration prevalent fifty years ago were largely due to the ignorance of the adulterator. His prototype of the present day is no more troubled with moral scruples than he was. The dissemination and absorption of knowledge has not been accompanied, as some rabid “educationalists’ would have us believe, by any improvements in morality and virtue. The “faker ” of to‐day is merely a more skilful “faker” than his predecessor. He knows the value and makes full use of “expert” assistance, both scientific and legal, for the purpose of facilitating his escape—easy enough in any case—from what grip there is in that cranky and lumbering legislative machinery which is innocently supposed by the majority of people in this country to act as a sufficiently effective deterrent and repressant.

One of the commonest excuses put forward in defence of the practice of treating milk, butter, meat, and other foods with ‘preservative’ drugs no longer possesses even the appearance of validity. Several of the large railway companies are adding refrigerator vans in considerable numbers to their rolling‐stock, and this fact should make it no longer possible for defendants to plead that the necessity of sending food‐products a long distance by rail involves the necessity of mixing preservative chemicals with them. Although the excuse referred to will not bear examination, it is a very specious one, and in those instances where evidence has not been brought forward to refute it, it has produced some effect on the minds of magistrates and others. It cannot be too often pointed out that such substances as boracic acid, salicylic acid, and formaldehyde are dangerous drugs, and that their unacknowledged presence in articles of food constitutes a serious danger to the public. Such substances are not foods, and are not natural constituents of any food. In most instances they are purposely introduced into food‐products to avoid the expense attending the proper production, preparation, and distribution of the food, or to conceal the inferior quality of an article by masking the signs of commencing decomposition or incipient putrefaction, and thus to enable a dishonest producer or vendor to palm off as fresh and wholesome an article which may be not only of bad quality, but absolutely dangerous to the consumer. The use of these substances, in any quantity whatsoever, and the sale of articles containing them, without the fullest and clearest disclosure of their presence, is as gross and as dangerous a form of adulteration as any which has at any time been exposed. In no single instance can it be shown that these drugs are, to quote the words of the Act of 1875, matters or ingredients “required for the preparation or production of a food as an article of commerce,” nor, of course, can it be contended that such substances are “extraneous matters with which the food is unavoidably mixed during the process of collection or preparation.” In reality, even under our inadequate and unsatisfactory adulteration laws, through which the proverbial coach‐and‐four can be so easily driven in so many directions, there ought to be no loophole of escape for the deliberate and dishonest drugger of foods. While the presence of preservative chemicals in any quantity whatever in articles of food constitutes adulteration, wherever the quantity is sufficient to allow the production of the specific “preservative” effect of the substance added, that fact alone is enough to make the food so drugged a food which must be regarded as injurious to the health of the consumer—in view of the inhibitory effect which, by its very nature, the antiseptic must produce on the process of digestion. To our knowledge the food market in this country is flooded with all sorts of inferior food‐products which are rarely dealt with under the Adulteration Acts, and which are loaded with so‐called preservatives. There will be no adequate protection for the public against the consumption of this injurious rubbish until the consumer sees the advantage of insisting upon an authoritative and permanent guarantee of quality with his goods, and until manufacturers of the better class at length find it to be a necessity for their continued prosperity that they should supply, apart entirely from their own statements, an independent and powerful guarantee of this kind.

In the days of our childhood we were told that the process of picking tea in China involved a preliminary purificatory ritual on the part of the picker. Thus, he ate no fish, indulged in baths, and dressed himself in clean clothes as essential preliminaries before pursuing his occupation. This may have been true so far as the tea that was to be consumed by the Chinese went. So far as this country was concerned, it is on record that somewhere about the year of grace 1850 the ingenious Celestial was sending us consignments alleged to contain silkworm‐dung faced with tea‐dust and a little Prussian blue, sand, and gum, and so forth, a decoction of this being drunk by certain inhabitants of this happy land under the firm belief that they were partaking of the “cup that cheers but not inebriates.” Such frauds were possible, as at that time but little attention had been paid to the subject of food chemistry, and no attention at all to the kind of food that was being eaten by the people of London and elsewhere. The subject of food was chiefly dealt with from the point of view of the requirements of the inland revenue, and so long as the Government obtained the duty that was demanded, but little heed was paid to the quality of the product taxed. Very recently we have had arriving at the docks a carge of foods from Hankow, China, consisting largely of frozen pigs. We are assured that these redoubtable porkers have been fed on rice, and while alive have been carefully tended. It is not stated that they were fed from golden troughs, or that they were slaughtered by, say, members of the Chinese aristocracy, but it is stated and assumed that they are all that any self‐respecting Englishman can possibly desire. A point in their favour is also made of the cheapness of the pork yielded by them. At the present time our food is nothing if not cheap, and “cheap food” has become a party cry whose success depends on the obsession of the minds of a large number of ill‐informed persons with the idea that the only attribute of a food which is worthy of consideration is its cheapness. The fact that we are receiving foodstuffs of the nature of meat from China is one that demands special and more serious consideration from the authorities in view of its possible prejudicial influence on public health, and the important changes that may take place in the nature and origin of our meat supplies. The consignment in question consists of game of various kinds, eggs, ducks, and pork. About 4,600 frozen pig carcases were unloaded. It is asserted that the pigs were fed on rice, or at all events on clean food, and there seem no grounds for disbelieving the truth of this statement; but the increase in this trade which is looked for from those financially interested in it does not necessarily mean that the goodness of future consignments is assured. The fact that the trade may greatly develop makes it difficult to see how a proper supervision can be maintained over the Chinese farmers who will presumably furnish the material of future consignments. Inspection in China is, however, imperatively demanded in the interests of public health on this side. Only a small proportion of the consignment we refer to has been put on the market up to the present, and this was subjected to a very careful and thorough inspection at this end before it was put on the market. The process of inspecting every carcase that may be landed is one that from the mere amount of time and labour involved presents serious difficulties, and the thawing process necessarily leads to a certain amount of deterioration. But if the trade in Chinese pork increases, and the resources of China to supply pigs to the world's markets are practically illimitable, we do not see how it will be possible to adequately inspect every consignment that comes across, while on the other hand no country requires more careful looking after than China in this respect. Inspection on the other side must apparently be left in the hands of the exporters, a most undesirable course to adopt, and one that should therefore not be encouraged. It need hardly be pointed out that the Chinese authorities can or will do nothing in the matter. For a system of inspection to be thorough and adequate, and such inspection is absolutely necessary in this case, it is needful to have inspectors who are experts at their work, capable of exercising independent judgment, and who are above suspicion. It is hopeless to expect to find such people among the ranks of the ordinary Chinese. The farmers whose stock and premises are to be inspected must also be people with some elementary notions of what is required of them. It need hardly he pointed out that no such state of affairs exists in China, and indeed, under present circumstances, is unthinkable, nor is it right that we in this country should run risks while a system of adequate inspection is worked out; in other words, that we should educate the Chinese farmer for his own benefit while running risks ourselves. It is stated that the stockyards and plant are well adapted for the work they have to do, and this we readily believe, but in an Oriental country in which there are no such things as health laws in existence, and where each man in this respect may do very much as seems right in his own eyes, the fact that we are obtaining from it an important article of food wherewith to feed large numbers of our poorer population is not one that can be viewed without serious apprehension as to the possible consequences. Stress has been laid on the fact that the pork is cheap, and that when an adequate system of inspection has been devised, the complete thawing out of the consignment will be no longer necessary and that Chinese pork will rank with the meat supplies that we obtain from the colonies. We have heard of the Greek Kalends, and it is possible that by the time they arrive the Chinese pig breeder and coolie will be a sufficiently cleanly person to be trusted with matters of this sort, but until that time does arrive we most strongly dissent from any line of action that would tend to shift any responsibility on to his shoulders. The pig is a dirty feeder, and the Chinese variety of the genus sus has the fullest opportunity for indulging his propensities for filth. He is also an animal peculiarly liable to various forms of disease of which swine fever is not the least objectionable. The care that is taken by the local authorities in this country regarding swine is sufficient evidence of this. But to make the British farmer conform to certain regulations while permitting pigs to be imported from China where no such regulations, or indeed, any at all, are enforced, seems to us to be the limit of hardship and absurdity. Sir PATRICK MANSON in the year 1881, at the request of the Chinese Government, made a careful examination of the bazaar pigs in Amoy. As a result of this examination he came to the conclusion that the flesh of such pigs was not sufficiently healthy to allow of its being safely eaten by Europeans at least. Though the proportion of pigs affected by Trichina spiralis was about 1 per cent., his conclusion was that with pork “cooked as the natives cook it, there can be little danger, but a roast leg of pork cooked in foreign style would certainly be a most dangerous dish.” The method adopted by natives was to cut the pork into small pieces and very thoroughly cook it. These were bazaar pigs, and of Amoy, which is far south of Hankow, but the bazaar pig in Hankow is probably not very different to his southern brother, and the conditions now in China are probably not much altered for the better since 1881. The pigs for the English market must be obtained from native breeders, and unless these breeders exercise unusual care in the feeding and housing of their stock, it is unlikely that any somewhat perfunctory system of inspection will do much towards‐mitigating the danger arising from The consumption of their pork It may be remarked that no people are more conservative than the Chinese, and to expect a Chinese peasant to radically alter his method of treating his stock, for reasons that he is entirely unable to appreciate, because there happens to be a market in England for the pork is really expecting too much. Nor does it seem that a consular invoice would be any real remedy. The time for insisting on consular invoices would probably be at the end of another series of “revelations,” and moreover, to attempt to make a consul professionally responsible for the soundness of large quantities of such pork, would be to impose a strange burden upon him.

The growing range of EEC Directives and Regulations for food products, some of which have never been subject to statutory control in this country, with compositional standards, and in particular, prescribed methods of analysis — something which has not featured in the food legislative policies here — must be causing enforcement authorities and food processors to think seriously, if as yet not furiously. Some of the prescribed methods of analysis are likely to be less adaptable to modern processing methods of foods and as Directives seem to be requiring more routine testing, there is the matter of cost. Directive requirements are to some extent negotiable — the EEC Commission allow for regional differences, e.g., in milk and bread — but it has to be remembered that EEC Regulations bind Member‐states from the date of notification by the Commission, over‐riding the national law. Although not so frequently used for food legislation, they constitute one of the losses of sovereign power, paraded by the anti‐market lobby. Regulations contain usual clauses that they “shall enter into force on the day following publication in the Official Journal of the European Communities” and that they “shall be binding in their entirety and directly applicable in all Member States”.

At a recent inquest upon the body of a woman who was alleged to have died as the result of taking certain drugs for an improper purpose, one of the witnesses described himself as “an analyst and manufacturing chemist,” but when asked by the coroner what qualifications he had, he replied : “I have no qualifications whatever. What I know I learned from my father, who was a well‐known ‘F.C.S.’” Comment on the “F.C.S.” is needless.

Generally speaking a “new” loaf is demanded and the baker who cannot deliver “new” loaves loses trade. But what is a “new” loaf? From the point of view of the chemist this question has formed the subject of innumerable investigations. A definition of a “new” loaf demands an understanding of “staleness” and the staling of bakery products is a subject of great complexity. The old idea was that it was entirely a question of the “drying out” of the bread, but cereal chemistry has proved that such a solution, namely the prevention of “drying out,” is only of partial efficacy; in fact “staleness” is caused by a change in the starch of the flour which is inherent in it and cannot be prevented by precautions which maintain the moisture content at a certain figure. The investigation of this type of staling has occupied the attention of many famous chemists, but the full explanation has not yet been obtained. Mass production has demanded many studies in that aspect of science known as “physical chemistry.” An example can be found in the preparation of certain sauces. Those of you who have made mayonnaise sauce know that to beat the olive oil into the mixture is fraught with difficulties. By means of the fork, used as a beater, the oil is distributed in very small particles through the mass of liquid, so that every globule of oil is separated from every other one. If the action docs not proceed properly the system breaks down and the mayonnaise “turns” and is spoiled. The manufacturer has to prevent this “turning,” not in a few pints but in hundreds of gallons. It is the chemist who has enabled him to do this and to manufacture with success those scores of salad‐dressings which are so delectable and the purchase of which relieves the housewife of so many hours of work and so much arm‐ache. An example of some interest is concerned with smoked salmon, which normally is a very variable product, whether it be the highly salted variety of the northern climes or the much less salted kind which has found favour in this country. The production of a lightly salted product is far more difficult than the more salted variety because much smaller changes in salt content become more noticeable. These small differences are so obvious to the confirmed smoked salmon eater that he detects not only the differences between one grade and another, but also the differences of salt content that occur in different parts of the same side of fish. It has fallen to the chemist so to change the methods of production of the lightly flavoured variety that the distribution of salt through the fish is even and the flavour therefore constant. This study of smoked salmon is only an example of the very big problem of standardisation, standardisation demanded by the consumer—and it follows that the big manufacturer must produce goods of standard flavour and appearance. Science steps in and gives the manufacturer those controls which enable him to produce, day in and day out, that standard range of article, whether it be ice‐cream or toad‐in‐the‐hole, Worcester sauce or cheese cakes, roast beef or jelly crystals. Modern science has introduced a new factor into our conception of what food should be. In the past it was only necessary to ensure that food should be “pure and wholesome,” by which was meant—in general terms—digestible and without any harmful constituents, be they natural or adventitious, bacterial or otherwise. So long as food complied with this broad definition everyone was satisfied. But biochemists and physiologists have demonstrated the importance of other factors, salts and vitamins, and it is necessary to consider the new situation thus created because it may be that the treatment of food to retain those substances may make it necessary to change preconceived notions. It may be that “palatability” may be affected, palatability which includes taste and appearance and odour. The whole subject is so complicated and, notwithstanding the enormous amount of work carried out, so little understood that no one as yet can be dogmatic, no one can state what are the optimum amounts of vitamins required by ordinary persons to keep them in good health. Having, however, decided the amount required, are we to try to preserve such quantities as occur naturally, or are we to fortify the food which we cat by added synthetic or even by purified natural vitamins? A further important consideration is whether the degree of maturity of, say, fruit in relation to maximum vitamin content coincides with optimum palatabilty. Certain it is that information gradually being accumulated on the importance—in many cases vital importance—of the minor constituents of foodstuffs leads to the conclusion that, to ensure the presence of all valuable minor constituents—be they known or unknown—the foodstuffs must, as articles of diet, be ingested almost in their entirety. This is probably an extreme view, for, in many cases, the result would be a product of reduced palatability or appearance, or, what is probably more important, “different,” and people do not like their food to be abnormal, i.e., to differ from their preconceived notion of what it should be. Nevertheless an “improvement” in the method of production, put into practice by the food manufacturer with the best intentions, may possibly result in a lowering of the dietetic value of the food, as, for example, by mechanical removal of an important part (the classical example being polished rice), by heat treatment, by oxidation or by materials added during cooking. The minor metallic constituents of food are gradually being revealed in their true importance. Copper, zinc, and iron are now known to be of importance. It is probable that every baby is born poor in calcium but rich in iron; milk, the natural food of the infant, is rich in calcium. It is only in the last few years that it has been shown that green vegetables as usually cooked are of very little real value. Cooking green vegetables in water containing sodium carbonate results in the almost complete destruction of the Vitamin C, and the discarding of the water removes the extracted salts. A green product certainly results but of greatly reduced nutritional value. On the other hand, it would appear that little destruction of vitamin activity takes place when the canning of vegetables or fruits is properly controlled. Sherman has said that attention to mineral salts and vitamins will lead to “buoyant” as distinguished from merely “passable” health. It is obvious that education of the public is essential if an intelligent use is to be made of the knowledge being gained by chemists and allied scientists. It is a most important fact that methods are being developed to assay foods for vitamins by chemical means. Biological feeding tests are obviously unsuitable for control purposes but, as the chemical identity of the vitamins becomes more clarified, chemical tests will become available for their determination. It is obviously the duty of the medical services of the country to guide the public as far as is possible on questions of nutrition. When such guidance becomes effective, the food producer will not be slow to see that his goods are up to the standard necessary, adding one more burden to the already loaded back of the chemist concerned with food production.

The necessity of standards of purity for certain kinds of agricultural produce being now recognised by the new Adulteration Act—4, (1)—no apology is needed for attempting to bring the application of the principle into actual practice. Some few standards have already been generally adopted, and the legalization of limits relating to many of those substances with which the Adulteration Acts deal would undoubtedly be welcomed.

In a recent issue of the Municipal Journal there appeared a short but apparently inspired article on the subject of London Government, in which is foreshadowed another drastic and apparently imminent alteration of the system of local administration at present in operation in the Metropolis.