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The change in climate and depletion of natural resources because of the harmful emissions from different materials becomes a main issue for the globe. Some of the developed and developing countries have focused on this issue and performed research to provide a solution. The purpose of this study is to identify the best types of concrete based on its impact on the environment and economy.

The life cycle assessment and life cycle cost analysis of six concrete mixtures that include construction and demolition wastes (CDW), marble sludge, rice husk and bagasse ash as a partial replacement of cement, are performed. These types of concrete are compared with each other and with ordinary concrete to select the best possible concrete type for a developing country, like Pakistan.

The results show that, although for an agricultural country like Pakistan, the agriculture wastes such as rice husk and bagasse ash are preferable to be used, if the emissions of CO₂ and CO from rice husk and NOx and SO₂ from bagasse ash are properly controlled. However, based on the results, it is recommended to use the CDW in concrete because of the small amount of air emissions and affordable prices.

Through this study, a path has been provided to construction companies and relative government organizations of Pakistan, which leads to sustainable practices in the construction industry. Moreover, the base is provided for future researchers who want to work in this area, as for Pakistan, there is no database available that helps to identify the impact of different concrete on the environment.

Silica extender pigments obtained from natural sources have been used in various coating systems for some time. A review of the microcrystalline silicas available to the paint formulator is included for reference purposes. Cost reduction and sheen control were recognised as attributes of ground natural silica. Properties of the finer or micronised natural silicas, such as lower pigment abrasion and low oil absorption, are covered to indicate potential contributions to the traditional or conventional as well as new coating systems.

Aluminium metal matrix composite (AMMC) is most popular in various industrial applications such as aerospace, automobile, marine, sports and many others. In common practice, silicon carbide, aluminum oxides, magnesium oxide, graphene and carbon nano tubes are the major reinforcing elements to prepare the AMMC. The purpose of this paper is to develop AMMCs reinforce with eggshell (ES) and rice husk ash (RHA).

Stir casting process is used for preparation of AMMC. From past few years, more emphasis is given to prepare the AMMCs using agro waste such as rice husk and/or ES as reinforcing materials. In this method, after the Al-matrix material is melted; it is stirred vigorously to form vortex at the surface of the melt, and the reinforcement material is then introduced at the side of the vortex. Stir casting process is a vortex and vigorous method to prepare the AMMCs. First, aluminum alloy (AA3105) is melted in the furnace when metal is in semisolid form. Reinforcement, i.e. ES and RHA are preheated at temperature 220°C and 260°C, respectively.

The result of AMMC shows that the tensile strength and hardness increased by using 22.41% and 45.5%, respectively, at 4.75 Wt.% each reinforcement, i.e. ES and RHA, and 1% Cr. The toughness and ductility of metal matrix composite (MMCs) have decreased up to 23.31% and 19.23% respectively by using 1% Cr, 4.75 wt. % ES and by 4.75 wt. % RHA of composite material.

In this work, Cr, waste ES and RHA have been used to develop green MMC to support the green revolution as promoted/suggested by United Nations, thus reducing the environmental pollution.

To study the degradation behaviour of borosilicate glass, which is suitable for hermetic sealing with Molybdenum and Kovar (Fe/Co/Ni) alloys, as a function of concentration and temperature in both acidic and alkaline media for long durations, up to 160 h.

The degradation (weight loss in mg/cm² of the glass sample) was determined by immersing the glass sample in HCl and NaOH solutions at different temperatures for different periods extending up to 300 h. The damage to the glass surface was seen under an optical microscope and the chemical species on the corroded surface were identified by electron spectroscopy for chemical analysis.

The borosilicate glass, having the nominal composition 0.70 SiO₂, 0.039 Na₂O, 0.028 K₂O, 0.21 B₂O₃, 0.01 Al₂O₃ was synthesized by melt and quench techniques. Degradation (corrosion) behaviour of this glass was investigated by immersing glass samples in 5 and 10 per cent HCl and 5 per cent NaOH solutions at different temperatures up to 90°C, for different periods and measuring dissolution rate (weight loss in mg/cm² of the sample). Dissolution rates were found to be 5.47 mg/cm² and 46.77 mg/cm² in 5 per cent NaOH at 60 and 90°C, respectively, whereas they were comparatively low (2.59 and 5.80 mg/cm² at 60 and 90°C, respectively, in 5 per cent HCl medium) after 160 h of total immersion period. The plot of dissolution rates against the temperatures showed the nonlinear behaviour at higher temperatures, probably due to the change in mechanism of corrosion. XPS studies exhibited the chemical species on the corroded surfaces. The optical microscopy of the corroded surface revealed that the corrosion mechanisms were different in acid and alkali media.

The degradation behaviour of borosilicate glass having a specific composition has been investigated as a function of concentration and temperature in both acid and alkaline media. The mixed alkali effect on the degradation behaviour may be studied by varying relative amount of Na₂O and K₂O in the glass composition.

The glass composition under the present study has been used for fabrication of matched type glass‐to‐metal (GM) seals with kovar alloy. In this respect the present study is significant in deciding the environmental conditions for its use.

The degradation behaviour of borosilicate glass having alkali and alkaline earth metal oxides has been investigated as a function of concentration and temperature in both acid and alkali media. The findings in this paper have the potential implications in deciding the environmental conditions for use of GM seals fabricated using this glass.

Recycled waste glasses have been widely used in Portland cement and concrete as aggregate or supplementary cementitious material. Compressive strength is one of the most important properties of concrete containing waste glasses, providing information about the loading capacity, pozzolanic reaction and porosity of the mixture. This study aims to propose highly nonlinear models to predict the compressive strength of concrete containing finely ground glass particles.

A robust machine leaning method called genetic programming is used the build the compressive strength prediction models. The models are developed using a number of test results on 50-mm mortar cubes containing glass powder according to ASTM C109. Parametric and sensitivity analyses are conducted to evaluate the effect of the predictor variables on the compressive strength. Furthermore, a comparative study is performed to benchmark the proposed models against classical regression models.

The derived design equations accurately characterize the compressive strength of concrete with ground glass fillers and remarkably outperform the regression models. A key feature of the proposed models as compared to the previous studies is that they include the simultaneous effect of various parameters such as glass compositions, size distributions, curing age and isothermal temperatures. Parametric and sensitivity analyses indicate that compressive strength is very sensitive to the curing age, curing temperature and particle surface area.

This study presents accurate machine learning models for the prediction of one of the most important mechanical properties of cementitious mixtures modified by waste glass, i.e. compressive strength. In addition, it provides an insight into the effect of several parameters influencing the compressive strength. From a computing perspective, a robust machine learning technique that overcomes the shortcomings of existing soft computing methods is introduced.

This study was conducted with the main purpose of recording primary data related to environmental factors, which has become the main criteria in the selection of the Sungai Batu Archaeological Complex (SBAC) as the center of the iron smelting industry and trade in ancient Kedah.

To fulfill this purpose, field studies involving drone photogrammetry mapping, augering, core drilling and geophysical mapping methods were carried out.

The results obtained through the application of the method have shown that SBAC has a good environment, which has a wide and deep river flow, the existence of Mount Jerai and the abundance of iron ores, mangrove Merbok and clay.

Resources did not allow for environment studies of the by-products tourism sites as part of the current study.

The study also included a survey and mapping to obtain potential primary data around SBAC in the process of developing it as the center of the world iron industry.

One finding is that attention to heritage policy and protection must be ongoing at all levels of government and the local community to ensure that the survey and mapping data carried out can be developed as a sustainable heritage tourism product.

This study reveals primary data related to the suitability of paleoenvironment in the SBAC development process as a world iron smelting industry area.

The unsatisfactory conditions which are created by the total lack of official standards, or indeed of any figures or definitions relating to food and some drug products is well illustrated in the report of a prosecution which appeared in last month's issue of the Journal. This case in question was dismissed by the Bench. The Bench was tendered some highly technical and very conflicting evidence. In view of this the defendants received the benefit of the doubt ; and they received this benefit because in the absence of any standard the Bench were unable to decide what was “ the nature, substance and quality demanded by the purchaser ” of the invalid wine—non‐alcoholic meat and malt wine—which was the subject of the prosecution. Wine may be defined as the juice of the grape which has been fermented under control conditions. The term has been extended in meaning and is now applied to a variety of substances which have had nothing to do with the grape and frequently contain very little or no alcohol, but may, as in this case, contain substances entirely foreign to the idea of wine, if the term be used in its original and restricted sense. A well known variety of ginger wine has an alcohol content of about 26 per cent. of proof spirit. So far as the alcohol content goes this liquid may be correctly described as a wine. It has, within its limits, the stimulating properties that are usually associated with an alcoholic drink and its value as an aid to digestion or a warm drink in winter cold has never been questioned. It appears that non‐alcoholic meat and malt wine also has virtues peculiar to itself dependent not on alcohol, but on other substances whose nature and quantity determine its characteristics. The term “ demand ” as used in the Act connotes the idea of a purchaser who well knows what he ought to get and furthermore will vigorously insist on getting it. The fact is, as everyone knows, that the purchaser is in a state of profound ignorance as to “ the nature, substance and quality ” of what he wishes to buy, and as a result he is in a sufficiently humble state of mind to accept without hesitation almost anything that may be told him about his prospective purchase from the other side of the shop counter. It is this state of mind on the part of the average purchaser and the desire to profit by it on the part of some food vendors that led to the passing of the Food and Drugs Act. The underlying idea being to protect the ordinary man and woman in health and pocket against the result of their purchasing adulterated material or inferior material described as being of superior quality. To enable the Act to be satisfactorily administered certain officers were appointed, known as Public Analysts. They were the officials of the old Local Government Board. They are the officials of the Ministry of Health. Their wide experience, special knowledge, and impartiality combine to make their services of peculiar value to the community so that they may, without unduly stretching language, be described as part trustees for the public health. Everyone will readily admit that there is scarcely anything, if anything, more complex than any one of our ordinary and unsophisticated food products. This complexity is, so to speak, raised to the second power by the variations that naturally occur in the essential constituents of these. The process of administering the acts directed against adulteration and similar offences has been frequently enlivened by the lively controversies to which this fact has given rise in the past and which it will no doubt do in the future. Another consideration must be taken into account. It is this. Since the year 1875 when the Food and Drugs Act became law the knowledge of food chemistry, in common with other kinds of knowledge, has increased rapidly in kind and in amount. This knowledge is now freely drawn on by those whose financial and business interests are bound up with food manufacture. As a result of this all kinds of more or less elaborately processed foods in immense variety and in many cases of a kind unthought of or impossible of manufacture sixty years ago have been put on the market. Among these processed products may be counted in considerable variety foods for the use of invalids or those convalescing from illness. Very large claims are made for these by the manufacturers, and it is only fair to say that these claims are to a considerable degree substantiated in the case of the better class of these substances prepared by reputable firms. All will agree that foods and stimulants which are said to have been specially prepared for the relief and more rapid recovery of a patient during the critical period of convalescence should be in every respect of such a nature as to be above suspicion and entirely beyond challenge by reasonable and expert opinion. This is unfortunately not always the case. Trade competition is acute. Official standards are non‐existent. Practically no official definitions exist, and no official figures to declare what shall be the minimum quantity of an essential constituent. The result is that nature is “ improved ”—to borrow a term which is in frequent and objectionable use among certain manufacturers—and the variation in the proportions of essential constituents depends on the taste and fancy of the manufacturer rather than on the needs of the consumer. Hence it comes about that to obtain a footing in a lucrative branch of trade a cheap product may be put on the market. It is cheap because it is made of inferior or adulterated materials, or what may be described as a vanishing quantity of an essential constituent is introduced. The quality of this constituent need not be in question. It is probably perfectly wholesome, but almost useless in such microscopic doses. For example, a mixture called “ chicory and coffee ” may be sold. The maker may please himself as to how much or how little coffee he uses, but as long as the coffee is not a purely subjective phenomenon he is on the right side of the law if he describes it as a mixture. Cheaper jams, it has been said, may be filled up with apple pulp. We may even suggest spent apple pulp which is certainly cheap and very filling at the price. As to the amount of essential constituent in the somewhat grandiloquently named “ Full Fruit Standard ” jams we may refer readers to the back numbers of this Journal. “ In bismuth tablets the amount of bismuth may become almost negligible because the law does not demand that there should be a fixed minimum present.” Many other instances could be given, and they would be found to relate to nearly every food and drink. In every case where the prosecution alleges that the nature or the substance, which is the basis of the prosecution, is below any reasonable standard the prosecuting authority finds itself heavily penalised by having no official standards to quote. The defence, on the other hand, gains what the prosecution has lost. It finds itself in a much stronger position if the case should be dismissed than when the proceedings commenced. The local authority has been put to great and perhaps useless expense in their endeavours to protect the public. The particular case of the meat and malt wine referred to appears to be an excellent instance of this kind of practice. The Public Analyst affirmed that a wine‐glassful of this “ wine ” contained 8¾ grains of meat extract, 52½ grains of malt extract, 150 grains of sugars (invert, etc.). The concoction was diastatically inactive. It contained no vitamins. It is further pointed out that the total cost of the contents of a pint bottle would be about three half‐pence. It is sold for four shillings and sixpence ! The report of the proceedings says that this “ wine ” was declared by the vendors to contain the juice of the finest grapes. The Public Analyst, however, certified that there was no grape juice in it. These facts and figures have not been called in question, and it is really somewhat difficult to speak with restraint of a transaction of this nature, especially when it is remembered that this, and other such “ wines ” and stimulants have been compounded for the alleged benefit of convalescents and of invalids. It is regrettable that experts can be found willing to support the doubtful claims of the manufacturers so far as it appears that they relate to the proportion of meat and malt extract in the “ wine.” The Public Analyst for the prosecuting authority stated that in his opinion such an article should contain a minimum of 4 per cent. of meat extract and 25 per cent. of malt extract. Another Public Analyst, called for the defence, said that in his opinion the proportions of these ingredients should be one and four respectively. Here are huge discrepancies in the ratio of about four to one in the essential constituents of an invalid food or stimulant. It is impossible, in the face of such wide differences of opinion among experts, to avoid drawing a comparison between the make up of the medical prescriptions which determine the nature of the drugs administered during illness and the nature of the stimulants, such as this “ wine,” which is to be taken during the period of convalescence. In the one case the prescription is drawn up by a medical man and the medicine compounded by a qualified pharmacist from drugs whose “ nature, substance and quality ” are rigidly defined in the pharmacopoeia. In the other case the stimulants which are presumably intended to help the patient on his road to recovery are, it appears, primarily made to sell, and have been compounded by the manufacturers to enable them to put money into their pockets. We can only say that if the same differences in composition existed in the same medicine and the same differences of opinion existed among medical men as to the efficacy of such medicine the patient would in all probability not reach the stage of convalescence at all. The only thing that might conceivably give trouble under the circumstances would be the wording of the death certificate. If medical men and analysts in official positions are to be regarded as joint trustees of the public health let them play the part. What would be thought of a trustee in the ordinary sense of the term who would recommend investment in a concern as to whose soundness there was considerable doubt? His good faith need not be called in question, but his judgment might certainly be described as faulty. It would be worse than a crime, it would be a mistake. A remedy for this unsatisfactory state may, in our opinion, be found in the setting up of standards for foods and drugs. The difficulties, of course, are great and a serious objection, or one of the objections, would be the inevitable lowering of the quality of most foods to the level of the minimum requirements of the law. There really seems to be no other way out of the difficulty, and if a beginning is to be made there seem to be very good reasons to begin with some of these invalid foods and stimulants. It is as much a matter for the medical man in cases of this kind as it is for the public analyst. If the medical man has succeeded in putting his patient after a serious illness on the high road to recovery he does not want to see him made to “ stand and deliver ” at the demand of anyone who has the necessary assurance to play such a part. With regard to standards in general a well known public analyst has recently observed : “ The Public Analyst should be umpire certainly, but if he is he should take into consideration the whole question of standards for any particular article ; long custom of the trade ; and also give weight to the needs and desires of the public.” He adds, “ The whole question of standards requires the attention of a small, but very competent, body—not a crowd.” This seems to be a complete statement of the case in few words. Some of the difficulties are suggested by the phrases “ custom of the trade ” and “ needs of the public.” It is the first of these that presents by far the most difficulty. The manufacturer well knows what “ custom ” would be of most benefit to him. He will fight for this by every means in his power. The fact that the public is extremely hazy as to its needs operates powerfully in favour of the manufacturer. It may also be added that while the manufacturers are almost always a well organised community, the members of the public are not, nor are they ever likely to be. It has been suggested that the public should be made “ food conscious.” It should “ take an interest in what it is buying ” and ask “ what do I expect to get when I buy this article? ” The meat and malt “ wine ” case is a sufficient answer. The purchaser paid four shillings and sixpence for what was stated to be “ three ha'porth of stuff ” made up to half a pint, and he was unconscious of the fact. This may be taken as a measure of the interest and knowledge shown by him when he was content to let the manufacturers make a profit of some three thousand per cent. on material that the Public Analyst is reported to have said was “ comparatively worthless.” While the magistrates were unable to accept the Public Analyst's standards as proved in view of the conflicting evidence, they added that the case had been most properly instigated by the West Riding County Council, and the defence was made to pay its own costs ! The whole case affords a clear demonstration of the urgent necessity of a small Standing Committee which could act and put its views into force without delay.

An investigation has been carried out of the catalytic action of iron dipalmitate on the polymerisation of styrene, and of lauryl mercaptan and oleic acid, and polystyrene having good particle size distribution has been obtained by the polymerisation of styrene in the presence of stearic acid, which can also act as a catalyst in the bulk polymerisation of this monomer, optionally used along with styrene oxide. The fatty acid has also been employed along with diphenylamine and hydroxyacetophenone, to give catalysts systems for the polymerisation of styrene monomer, the acid ensuring brilliance in the moulded polymer. Stearoyl peroxide functions as a catalyst in the bulk polymerisation of styrene, whilst zinc stearate can work as a catalyst to the thermal degradation of polystyrene.

Introduction The behaviour of metals at elevated temperatures in an oxygen atmosphere depends upon the protection afforded to the metal by the oxide film. Highly reactive metals such as sodium and potassium form discontinuous oxide films that provide no protection, and consequently oxidation proceeds according to a linear law—the reactive aluminium forms a protective film, but its application is limited by its low melting point. Metals like gold and platinum are inert in oxygen, but their high cost precludes their use for most high temperature engineering applications. Thus, the major part of this branch of industry is dependent on iron and iron‐base alloys for its material requirements.

Inefficient waste disposal technique and cement production methodology caused significant environmental impacts, leading to global warming. The purpose of the research was to invent an effective, sustainable technology to use the wastes and alternate for cement in concrete. Geopolymer technology could be the most desirable solution to use the wastes into an effective product.

The wood waste ash derived from nearby tea shops was used as an alternate binder for fly ash. The replacement of WWA with FA was varied from 0 to 100% at 10% intervals. In this research, setting and mechanical features of Geopolymer Concrete (GPC) along with Waste wood ash (WWA) was carried out. The influence of wood waste ash in the microstructure of the GPC was also assessed using scanning electron microscope and X-ray diffraction analysis.

The findings revealed that 30% replacement of wood waste ash was performed higher in all measured features. Besides, the formation of different phases was also observed with the inclusion of wood waste ash.

The demand for fly ash was increased in recent years, and the fly-based GPC has required more alkaline solution and temperature curing. Hence, there was a research gap on finding an alternative binder for fly ash.

The research novelty was to use the wood waste ash, which has inbuilt alkaline compounds on the production of sustainable geopolymer. The finding showed that the wood waste ash could be alternate fly ash that eliminates the environmental impacts and economic thrust.