Commercial-scale Trials Research Articles

Potential of semi-soft coals as replacement for hard coals in stamp charging blend

In India the use of appropriate imported coals to supplement the inherent deficiencies of indigenous coals for cokemaking is in vogue. Stamp charging is very efficacious for inferior coking coals and has enabled Tata Steel to produce coke of international quality. It has been found to offer scope for the utilisation of less expensive imported semi-soft coals to replace expensive imported hard coals. Extensive tests were carried out to assess the blending potential of semi-soft coals for cokemaking by stamp charging in a 7 kg mini-oven, and a 600 kg pilot oven in the laboratory. This was followed by commercial scale trials. The test results clearly indicated that hard coals can be replaced with 30–35% of semi-soft coals in the stamp charging blend at Tata Steel without any compromise of coke strength. Semi-soft coals are now in regular use in all Tata's stamp charged batteries.

Production of anthocyanins by plant cell cultures

Anthocyanins, responsible for the various attractive colors in plants, are becoming important alternative to many synthetic colorants due to increased public concerns over the safety of artificial food colors. Production of anthocyanins by plant cell cultures has been suggested as a feasible technology that has attracted considerable industrial and academic interests in the past two decades. This paper is to provide an overview of the present status and the future prospects in the commercial development of plant cell cultures for production of anthocyanins. The focus is on the strategies for enhancement of anthocyanin biosynthesis to achieve an economically viable technology for commercial applications. Through strain improvement, optimization of media and culture conditions, and intelligent process strategies such as elicitation and two-stage system, significant enhancement in productivity has been achieved in a number of cultures. However the yield of anthocyanins obtained so far is still far away from the full potential of anthocyanin synthesis by plant cell cultures. Further improvements require the insights on the regulation of anthocyanin synthesis, accumulation, storage and breakdown that will eventually lead to genetic manipulation of anthocyanin biosynthesis. Many studies have elucidated the metabolic pathway of anthocyanin biosynthesis. Preliminary studies on the regulation of anthocyanin biosynthesis on the levels of genes and enzymes are reviewed, showing that it is feasible to clone genes from secondary metabolism with an improved yield of anthocyanins. There is currently no commercial-scale trial for production of anthocyanin by plant cell cultures, but an intelligent integration of those existing strategies could provide a technology for industrial application competitive to the current production methods.

Effects of Swathing on Yield and Quality of Spring Canola in Northern Idaho

Spring canola (Brassica napus L.) is a new crop in the Pacific Northwest and growers have adopted cultural practices used in western Canada where spring canola (or rapeseed) must be swathed to hasten maturity and avoid frost damage. The aim of this study was to evaluate the effect of preharvest swathing on the seed yield and seed quality, and determine the best time to swath in northern Idaho, if swathing is needed. Five spring canola cultivars were planted in 1992 and 1993 to compare seed yield and quality of swathed and direct harvest crops. In 1994, commercial agricultural machinery was used in larger plots, to compare seed yield and quality from three different swathing dates with direct harvest. In 1992, directly harvested canola had higher yields than swathed canola. The following year, yield of directly harvested and swathed canola were not different. In commercial scale trials, yield loss was linearly related to time of swathing with the least reduction occurring when swathed at 60 to 80% brown seed, and most yield loss occurring when swathed at 10 to 20% brown seed. Therefore, optimal swathing time would be when most seeds were brown. Swathing canola resulted in smaller seed and greater chlorophyll content. However, swathed crops had lower seed moisture content, which may ease harvest operations. We recommend that canola should only be swathed in northern Idaho in cool and wet growing seasons, where harvest is delayed.

Fipronil seed treatments for the control of chironomid larvae (Diptera: Chironomidae) in aerially-sown rice crops

The phenyl pyrazole insecticide fipronil was bioassayed against final instar larvae of Chironomus tepperi Skuse, and found to be highly toxic (LC 50 0.43 μg l −1, LC 90 1.05 μg l −1) relative to conventional organophosphorus insecticides. A comparison of fipronil and malathion (the standard bloodworm seed treatment in use in New South Wales) under glasshouse conditions using model soil/water systems showed that fipronil at 0.005 mg l −1 gave superior residual control to malathion at concentrations of up to 0.6 mg l −1. In small plot trials fipronil applied to pregerminated seed provided control of Chironominae at 12.5 and 25 g active ha −1 at least equivalent to that provided by the standard 300 g active ha −1 malathion treatment. The 12.5 g active ha −1 rate provided between 9 and 14 days residual control of Chironominae, whilst raising the application rate to 50 or 100 g active ha −1 increased residual control to between 14 and 19 days and provided significantly better control than malathion. Other chironomids (predominantly Tanypodinae) were strongly suppressed by all rates of fipronil for all or most of the 34-day trial period. Plant establishment and shoot length were significantly greater in all fipronil treatments relative to both the malathion standard and the untreated control. There was also evidence of stronger root system development in the fipronil treated plants. At an initial application rate of 12.5 g active ha −1, fipronil levels in the water column declined from 2.1 μg l −1 1 day after sowing to 0.01 μg l −1 14 days after sowing (DAS). At 22 DAS the parent compound was below detection limits (0.005 μg l −1). Four unreplicated commercial scale trials of fipronil were conducted in which three treatments or treatment combinations were evaluated. In general, fipronil (12.5–15.75 g active ha −1) either alone or followed by a post-sowing chlorpyrifos treatment (75 g active ha −1 10–15 DAS) provided a level of control equivalent to paired chlorpyrifos applications (75 g active ha −1 at 2–5 and 10–17 DAS), but at one site fipronil alone was inadequate without a post-sowing chlorpyrifos treatment. Our results indicate that fipronil applied to seed at 12.5 g active ha −1 is a more efficacious seed treatment than malathion at 300 g active ha −1 and provides protection against chironomids for 9–14 DAS. An additional post-sowing insecticide application may still be required in some seasons, but should only be applied in response to high larval populations and evidence of crop damage.

Two major metallocene joint ventures formed

Two major deals were announced last week pitting metallocene catalyst rivals Dow Chemical and Exxon against each other in licensing linear low-density polyethylene technology. One joint venture links Dow Chemical with BP Chemicals; the other, Exxon Chemical with Union Carbide. The Dow-BP Chemicals' venture will combine Dow's Insite metallocene technology with BP's Innovene high-productivity gas-phase polyethylene technology, introduced early last year (C&EN, Jan. 23, 1995, page 8). The combined technology will be licensed to other polyethylene producers. The two companies began joint development of Insite and Innovene technologies in the second half of 1995. Working at BP's pilot plant in Lavera, France, near Marseilles, the two companies say they have proved out the combined technology, and they will soon expand trials to BP's semicommercial plant in Lavera, leading up to commercial-scale trials in 1997. The technology package will be ready for 1997 commercial delivery, say the companies, essentially as ...

Commercial scale trial of an economical schedule for boron impregnation treatment of green rubber wood

An economical treatment schedule, developed at the Kerala Forest Research Institute for boron impregnation of rubber wood, was tested in a commercial wood treatment plant. A pooled mean dry salt retention (DSR) of 12.4 kg/m3 was achieved for rubber wood in green condition with average moisture content of around 70%, using a 6% boric acid equivalent solution. This confirms the success of the schedule for commercial application, as the DSR achieved is much higher than the standard specification of many countries.

New fish resources of reservoirs in Sri Lanka. 3. Results of commercial-scale trials and yield estimates of a gill-net fishery for minor cyprinids

It has been established that the indigenous cyprinids, which are all minor carps, which have successfully colonized Sri Lankan reservoirs could be exploited by the introduction of a subsidiary gill-net fishery without apparent detrimental effects, due to the capture of juvenile fish, on the existing gill-net fishery dominated by the exotic Oreochromis mossambicus (Peters). In this paper, the results of commercial-scale trials, using 15- and 28-mm mesh-size multi-filament gill nets carried out simultaneously by the survey team and commercial fishermen in six reservoirs are presented. The results of the survey team and the commercial fishermen were almost identical with respect to landings of cyprinids, O. mossambicus and other forage species. The results confirm the feasibility of a subsidiary gillnet fishery for cyprinids in Sri Lankan reservoirs. The potential yield from such a fishery was estimated using an indirect approach in which the species composition during the experimental gill-net surveys and the existing commercial fishery was taken into consideration; the ratio of minor cyprinids to O. mossambicus landings per unit of netting was used as an index of the relative abundance of the two groups. On the basis of this computation, the yield is estimated to range from 35 to 2191 kg ha −1 year −1 in reservoirs of widely different hydrological and hydrobiological characteristics, with a mean of 907 kg ha −1 year −1. It is estimated that a well managed subsidiary gill-net fishery in the major perennial reservoirs of Sri Lanka could yield 90 700 ton year −1.

Controlled atmosphere storage of winter white cabbage

SUMMARYIn four laboratory experiments and five commercial scale trials carried out between 1977 and 1979, five cvs of winter white cabbage were stored at 0–2 °C for 29–43 wk in controlled atmospheres (C A) consisting of c. 5–6% CO2, 3% O2 and the remainder N., or in air. The incidence of rots caused by Botrytis cinerea was reduced and the incidence of ‘pepper‐spotting’ (a non‐microbial leaf necrosis disorder) was reduced or eliminated by storage in CA. Storage and trimming weight losses were lower and the recoveries of trimmed cabbage suitable for marketing or processing up to 22% higher in cabbage stored in CA than in those stored in air. Sensory assessments of four cvs tested indicated that CA‐stored cabbages retained their green colour, crisp texture and fresh flavour better than the corresponding air‐stored samples.

Recent Developments in the Use of Herbicides in Rubber and Oil Palm

Abstract Recent developments in the use of herbicides during the establishment of leguminous cover crops and the mature phases of rubber and oil palm plantings are discussed. Results of 12 semi-commercial and commercial scale trials showed that chemical weeding using paraquat and diuron post-emergence or oxyfluorfen pre-emergence with supplementary manual or chemical control was considerably cheaper than exclusive manual weeding during the six months following the sowing of legumes. Reductions in weeding costs ranged from 6 to 66%. In the mature phase a wide range of herbicide treatments involving extensively used herbicides such as paraquat, MSMA, 2, 4-D amine and sodium chlorate for the suppression of weed growth along rubber tree rows and in oil palm circles and harvesters' paths were compared. Results indicate that there are several suitable alternatives to sodium arsenite, a formerly widely used herbicide which is now banned for general weed control. In both crops, the most cost effective treatments ...

Título en español.

El agente químico madurativo de la caña de azúcar, Polaris, [N, N-bis (phosphonomethyl) glycine], se evaluó, en pequeñas parcelas repetidas y en pruebas comerciales para determinar las cantidades óptimas y la época de aplicación más apropiada. En el experimento de parcelas repetidas, donde se aplicó el Polaris al comienzo de la cosecha (enero-febrero), se encontró que aplicaciones de 2.24, 4.48 y 6.72 kg./ha. aumentaron significativamente el contenido de sacarosa en caña y sobre el testigo sin tratar, en muestras tomadas 6 semanas después de aplicado el producto. La aplicación de 6.72 kg./ha. aumentó significativamente el contenido en sacarosa sobre la de 2.24 kg./ha. Luego de 8 semanas de aplicado el Polaris, solamente la aplicación de 6.72 kg./ha. produjo aumentos significativos sobre el testigo sin tratar. Aplicado en las postrimerías de la zafra (mayo-junio), a razón de 6.72 kg./ha. evitó en forma significativa reducciones en el contenido en sacarosa en muestras tomadas a las 2 y 4 semanas, pero no tuvo efecto significativo a las 6 y 8 semanas. La aplicación a razón de 6.72 kg./ha. al comienzo de la cosecha causó un aumento medio de 12.9% con un contenido en sacarosa (10.74 vs 9.51) sobre el testigo, mientras que el correspondiente aumento para la aplicación tardía (mayo-junio) fue de 7.3% (10.44 vs. 9.73). En las pruebas comerciales donde se aplicó el material a razón de 3.36 kg./ha. por avión en la zona húmeda de la costa norte, y la costa sur bajo riego, se encontró un efecto significativo al combinar las pruebas efectuadas en la costa norte con aumentos en el contenido de sucrosa entre 9 y 15% sobre el testigo en muestras tomadas 4 semanas luego de aplicado el Polaris.

Colour retention in fresh meat stored in oxygen—a commercial scale trial

SummaryAged fresh beef was conventionally packaged at a central cutting plant and transported in oxygen filled containers to a retail outlet where it was compared in a refrigerated display cabinet with similar meat held in air. Colour deterioration during transport and storage was successfully delayed by holding in oxygen and the process was most effective in muscles prone to rapid discolouration. Even a small rise in temperature accelerated discolouration so that good refrigeration during display was still essential.

EFFECT OF FIVE INSECTICIDES ON POPULATIONS OF THE SIX-SPOTTED LEAFHOPPER AND THE INCIDENCE OF ASTER YELLOWS IN CARROTS

Five insecticides were evaluated for their ability to control the aster leafhopper, Macrosteles fascifrons (Stål), and to reduce the incidence of aster yellows disease, transmitted by this vector in carrots. Furadan (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) as a single granular treatment at seeding was as effective in reducing the level of aster yellows disease as five or eight foliar treatments with carbaryl (1-naphthyl N-methylcarbamate) in 1967 and 1968. Oxydemeton-methyl (O,O-dimethyl S-[2-(ethylsulfinyl)-ethyl]phosphorothioate) was comparable with carbaryl in reducing aster leafhopper numbers and incidence of aster yellows disease. Disulfoton (O,O-diethyl S-[2-(ethylthio)ethyl]phosphorodithioate) as a single granular application at seeding was the least effective treatment in this study. Aster yellows incidence in carrots treated with DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane] was only slightly lower than with carbaryl in a commercial scale trial. A 5-day insecticide spray schedule was not appreciably more effective than a 10-day schedule.

THE INFLUENCE OF VACUUM PRESSING ON THE TEXTURE OF CHEDDAR CHEESE*

SummaryA study was made of the influence of several factors on the texture of young and mature vacuum‐pressed rindless cheese. Pressures greater than 26 lb/in2 were required for maximum improvement in texture. A vacuum of 15 in was less effective than a vacuum of 25 in. Vacuum pressing of ‘dressed’ cheese for 5 min was almost as effective as vacuum pressing for 17 h; vacuum pressing after dressing was more effective than before dressing; transfer of vacuum‐pressed cheese to a normal press for the completion of pressing did not affect texture. Vacuum treatment of curd before hooping and pressing in the normal way had no beneficial effect on texture; vacuum pressing improved the texture of cheese made with mixed‐strain starters although this cheese was not as close as vacuum‐pressed cheese made with single strain starters.The distinct improvement in cheese texture which resulted from some combinations of vacuum pressing condition was confirmed in commercial scale trials involving 2,540 rindless cheese. This improvement was evident when cheese were graded at two weeks and when regraded at maturity.

Studies on the manufacture of sweet cream starter butter: II. Effect of variation in proportion of starter added to cream

SummaryProduction of diacetyl and acetoin by starters in cold skim-milk and cream was shown to increase with increase in the proportion of starter culture added, with some limitations at the higher rates of starter addition.With Streptococcus diacetilactis starter in skim-milk at 50°F the relation between proportion of starter added and production of diacetyl was linear up to addition at the 4% level, whereas at 43°F it was approximately linear up to the 10% level. At both 50 and 43°F the relation between the proportion of starter added and the production of acetoin was linear up to the 10% level.With Camb starter in skim-milk at both 50 and 43°F there were regular increases in production of diacetyl up to the 4% level of addition, but only minor changes thereafter with increase in the proportion of starter added up to 10%. At both temperatures the maximum production of acetoin was reached with the 7% rate of addition.Production of diacetyl and acetoin in skim-milk was greater at 50°F than at 43°F with both starters for all proportions up to 10%, and it was greater for Str. diacetilactis than for the mixed cultures.Except at the higher rates of addition of starter and at the higher temperature there were no concomitant increases in the acidity of the milk or lowering of the pH values. It appears that at low temperatures production of diacetyl by starters in sweet milk and cream proceeds independently of production of lactic acid.Similar results were obtained in a series of experimental buttermaking trials and some small commercial-scale trials, in which varying proportions of starter were added to creams after pasteurizing and before holding overnight for churning. With the cream-holding temperatures used, mainly 40–50°F, the pH values of the butters were not appreciably lowered by the starter additions to the cream. At all the rates of addition there were with Str. diacetilactis starter higher contents of diacetyl in the butter than with Camb starter. There was no indication of any relationship between the proportion of starter added and the keeping quality of the butter.

THE APPLICATION OF DUST-LAYING OIL TO WOOL

A process is described for the application of dust-laying oil to woollen blankets, in which use is made of a positively charged oil-in-water emulsion. During a commercial-scale trial of this process, difficulty was encountered in the form of a progressive build-up of oil and fatty acid after repeated laundering and oiling. The inclusion in the laundering formula of modified soda in a soap: soda ratio of 3:1 has been found to give satisfactory control of the fatty acid content, and to assist greatly in preventing the accumulation of oil.