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In this study, new hybrid polymers composed of Zinc chloride (ZnCl₂), acrylamide and chitosan were prepared at different ratios and temperatures. The effects of pH and polymer dosage were examined for different polymers to observe their efficiency in the removal of turbid water. The polymers’ zeta potential, morphology, elemental composition and functional groups were also identified and studied.

The free-radical polymerisation process was executed in the presence of N, N’-Methylene bis-acrylamide and potassium persulphate in one molar acrylamide solution. ZnCl₂ and chitosan (CO) were later introduced into the suspension under nitrogen gas flow. Ratio and temperature were varied during polymerisation. The hybrid polymer produced, termed Polyacrylamide + chitosan oligosaccharide + zinc chloride (PAMCOZ), was analysed using Fourier transform infra-red spectroscopy attenuated total reflectance and scanning electron microscope with energy dispersive X-ray. The hybrid PAMCOZ was experimented with in high turbid kaolin suspension using jar testing analysis to see its ability as a coagulant.

The coagulation process using PAMCOZ with a ratio of 11 (3:2) at 70°C surrounding temperature showed a 100% reduction at pH 4 with 50 mg/L of the polymer. The functional groups present in ratio 11 polymer were hydroxyl, carbonyl, amide and methyl groups. In addition, several elements were spotted on the surface of PAMCOZ, such as zinc (Zn), carbon (C), chlorine (Cl), nitrogen (N) and oxygen (O). The effect of pH also demonstrated that PAMCOZ was unfavourable in an alkaline turbid water environment.

Due to the research methodology approach, the research results may lack actual wastewater application. Therefore, researchers are encouraged to test the hybrid coagulant on raw wastewater, such as pulp and paper mill effluent with a high turbidity value similar to this study.

The polymerisation between zinc chloride, acrylamide and chitosan has not yet been applied. The different ratios and effects of temperature were analysed on PAMCOZ to see the turbidity removal. PAMCOZ showed better turbidity removal in acidic conditions.

If additional evidence were needed of the connection between food supply and the spread of infectious disease, it would be found in a report recently presented to the Finsbury Borough Council by its Medical Officer of Health, Dr. GEORGE NEWMAN. It appears that in the early part of May a number of cases of scarlet fever were notified to Dr. NEWMAN, and upon inquiry being made it was ascertained that nearly the whole of these cases had partaken of milk from a particular dairy. A most pains‐taking investigation was at once instituted, and the source of the supply was traced to a farm in the Midlands, where two or three persons were found recovering from scarlet fever. The wholesale man in London, to whom the milk was consigned, at first denied that any of this particular supply had been sent to shops in the Finsbury district, but it was eventually discovered that one, or possibly two, churns had been delivered one morning, with the result that a number of persons contracted the disease. One of the most interesting points in Dr. NEWMAN'S report is that three of these cases, occurring in one family, received milk from a person who was not a customer of the wholesale dealer mentioned above. It transpired on the examination of this last retailer's servants that on the particular morning on which the infected churn of milk had been sent into Finsbury, one of them, running short, had borrowed a quart from another milkman, and had immediately delivered it at the house in which these three cases subsequently developed. The quantity he happened to borrow was a portion of the contents of the infected churn.

A study was designed to investigate the chemical coagulation process for the treatment of the potato food industry wastewater of the “Chipsy factory” located at Abi‐Sier, Egypt. The chemical coagulants used in the study include alum, ferric chloride, calcium chloride, ferric sulphate and Nalco as polymer. Variable doses of these coagulants were examined to determine the optimum dose. Results obtained showed that chemical treatment (coagulation, flocculation, followed by sedimentation) was efficient to reduce the chemical oxygen demand (COD), total suspended solids (TSS) and turbidity significantly. Remarkable variation of the removal efficiency depends on the type of coagulant. Ferric chloride and ferric sulphate were more efficient than calcium chloride. Combination of Nalco with each of the studied coagulants improved the removal efficiency remarkably. Reduction of 91‐94 per cent of turbidity, 93‐97 per cent of COD, and 94‐97 per cent of the TSS was achieved with these combinations.

The objective of this work is studying the use of chemicals to enhance primary treatment in municipal wastewater treatment plants, thereby reducing the cost of the secondary treatment stage. Jar tests using chemicals, polymers and sea water have been conducted to determine the best performing chemicals, alone and in combinations. The process performance parameters studied were pH, type and dosage of coagulant, mixing intensity, detention time, settling time and addition of coagulant aid. The efficiency of the process has been measured as percentage removals in COD, TSS, turbidity, settleable matter and removals of heavy metals. The results proved the improvement of removal efficiencies.

A novel ternary flocculant was prepared by a simple compounding method to achieve efficient and rapid mud-water separation. This paper aims to discuss the possible mud-water separation mechanism.

This experimental study aims to investigate the effects of different types of flocculants on the separation of waste mud water and the degradation of flocculants in the supernatant. The flocculating component, the ratio of the flocculating accelerator to the flocculant and the addition amount of the novel ternary flocculant were optimized.

The experimental results show that the composition of the new ternary flocculant is cationic polyacrylamide (CP-02), grafted starch (GS-501) and flocculation sedimentation accelerator, the best effect, the mass ratio is 1:0.5: 0.75. According to 0.25:1 (volume ratio), the new ternary flocculant is pre-configured into a solution with a concentration of 3 kg/m³ to achieve efficient and rapid mud-water separation.

The new ternary flocculant is used for the separation of mud and water in the underground continuous wall waste mud, improving the level of civilized construction.

A graft copolymer (PBW-g-PAM) of Moringa seed was prepared. The phosphate buffer washed seed powder and polyacrylamide were reacted, using ceric ion initiator. The grafted copolymer was tested for its efficiency for metal removal (Cr-VI) from tannery effluent and for color removal from textile effluent using standard spectroscopic methods. The paper aims to discuss these issues.

The PBW-g-PAM was prepared by standard method and characterized by FT-IR, SEM, UV-vis, XRD and DSC/TGA analyses.

The effects of PBW-g-PAM dose, contact time and pH on percent removal of Cr-VI and dye color, have been reported.

The efficiency of metal removal was shown to be 99 per cent in just 15 min. Similar results were obtained for efficient color removal from textile effluents. It is for the first time that graft polymer of Moringa seed has been used for metal and color removal.

Motivated by the globally increasing concern over environmental protection, the interest of a large part of the scientific community focuses on the development of green surfactants aiming to replace traditional toxic surfactants-based alternatives. The purpose of this paper is to prepare acrylate copolymer latex modified with fluorine and silicone monomer, which is emulsified with the green surfactants of sodium rosinate and alkyl polyglycoside (APG).

A series of acrylic copolymer latexes containing fluorine–silicon have been prepared by semi-continuous seed emulsion polymerisation of mixed monomers of methyl methacrylate (MMA), butyl acrylate (BA), hexafluorobutylmethacrylate (HFMA) and vinyltriethoxysilane (VTES) and emulsified by green mixed surfactants of sodium rosinate and APG.

The optimum recipe of preparing the emulsion is as follows: the amount of emulsifiers is 6 per cent and the mass ratio of sodium rosinate to APG is 1:3. The amount of initiator is 0.4 per cent, and the amounts of the silicon monomer and fluorine monomer are 5 and 7 per cent, respectively. In comparison with the acrylate latex prepared without fluorine monomer and silicon monomer, the thermal stability and the water resistance of the film of the resultant latex clearly improved.

The acrylic copolymer latexes containing fluorine–silicon emulsified with green surfactants can be used in the coatings, adhesives, finishing agents and so on.

The acrylic copolymer latexes containing fluorine–silicon have been prepared by semi-continuous seed emulsion polymerisation. The green mixed surfactants of sodium rosinate and APG have been used as the emulsifiers to replace traditional toxic surfactants-based alternatives.

In its passage through the Grand Committee the Food Bill is being amended in a number of important particulars, and it is in the highest degree satisfactory that so much interest has been taken in the measure by members on both sides of the House as to lead to full and free discussion. Sir Charles Cameron, Mr. Kearley, Mr. Strachey, and other members have rendered excellent service by the introduction of various amendments; and Sir Charles Cameron is especially to be congratulated upon the success which has attended his efforts to induce the Committee to accept a number of alterations the wisdom of which cannot be doubted. The provision whereby local authorities will be compelled to appoint Public Analysts, and compelled to put the Acts in force in a proper manner, and the requirement that analysts shall furnish proofs of competence of a satisfactory character to the Local Government Board, will, it cannot be doubted, be productive of good results. The fact that the Local Government Board is to be given joint authority with the Board of Agriculture in insuring that the Acts are enforced is also an amendment of considerable importance, while other amendments upon what may perhaps be regarded as secondary points unquestionably trend in the right direction. It is, however, a matter for regret that the Government have not seen their way to introduce a decisive provision with regard to the use of preservatives, or to accept an effective amendment on this point. Under existing circumstances it should be plain that the right course to follow in regard to preservatives is to insist on full and adequate disclosure of their presence and of the amounts in which they are present. It is also a matter for regret that the Government have declined to give effect to the recommendation of the Food Products Committee as to the formation of an independent and representative Court of Reference. It is true that the Board of Agriculture are to make regulations in reference to standards, after consultation with experts or such inquiry as they think fit, and that such inquiries as the Board may make will be in the nature of consultations of some kind with a committee to be appointed by the Board. There is little doubt, however, that such a committee would probably be controlled by the Somerset House Department; and as we have already pointed out, however conscientious the personnel of this Department may be—and its conscientiousness cannot be doubted—it is not desirable in the public interest that any single purely analytical institution should exercise a controlling influence in the administration of the Acts. What is required is a Court of Reference which shall be so constituted as to command the confidence of the traders who are affected by the law as well as of all those who are concerned in its application. Further comment upon the proposed legislation must be reserved until the amended Bill is laid before the House.

The purpose of this paper is to present a numerical analysis of the laser surgery of port wine stain (PWS) with cryogen spray cooling to compare the treatment effect between pulse dye laser and Nd:YAG laser, explain the incomplete clear of the lesion and optimize the laser parameter.

The complex structure of skin and PWS is simplified to a multi-layer skin model that consists of top epidermal layer and underneath dermis layer embedded with discrete blood vessels. The cooling effect of cryogen spray before laser firing is quantified by a general correlation obtained recently from the experimental data. The light distribution is modeled by the Monte Carlo method. The heat transfer in skin tissue is calculated by Pennes bioheat transfer model. The thermal damage of blood vessel is quantified by the Arrhenius damage integral.

For the vessel size studied (10-120 µm), pulse duration is recommended shorter than 6 ms. Large and deeply buried vessels, which may survive from 595 nm laser irradiation, can be coagulated by 1,064 nm laser due to its deep light penetration depth in skin. Furthermore, a desired uniform heating within the large vessel lumen can be achieved by 1,064 nm laser whereas 595 nm laser produce non-uniform heating.

The possible reason for the poor responding and incomplete clearance lesions is clarified. Laser wavelength and pulse duration are suggested to improve the clinical results.

Industrial progress is in large measure a function of the scientific understandings inherent in a given body of technology. It is, of course, true that technology can be developed empirically and much of it has been. It is also true, however, that technology based on scientific understandings is in practically every instance more effective. If only empiricism is involved there inevitably comes a time when technological progress ceases. It is for this reason that scientific studies in the coatings industry must be continually encouraged.