Quality Of Lime Research Articles

Combined postharvest UV-C and 1-methylcyclopropene (1-MCP) treatment, followed by storage continuously in low level of ethylene atmosphere improves the quality of Tahitian limes.

The green Tahitian limes (Citrus latifolia) were exposed to 7.2kJm-2 UV-C and 0.5μLL-1 1-methylcyclopropene (1-MCP) treatments both separately and in combination. After treatment, fruit were stored in ethylene free (i.e. air containing < 0.005μLL-1) or 0.1μLL-1 ethylene at 20°C and 100% RH. The results showed that UV-C treatment delayed skin degreening and reduced endogenous ethylene production compared to untreated control fruit, however these effects reduced over the storage time. As expected, 1-MCP inhibited ethylene production, reduced calyx abscission and retained peel greenness during the storage. Both of the combination treatments, 1-MCP + UV-C and UV-C + 1-MCP reduced endogenous ethylene production and delayed skin yellowing. In all treatments, UV-C and 1-MCP resulted in lower fruit respiration rates than untreated control fruit, however this effect diminished during 7 and 14days storage for fruits stored in air and 0.1μLL-1 ethylene atmosphere, respectively. There was no difference in weight loss, SSC, TA and SSC/TA ratio between the treatments and storage conditions. The results suggest that a pre-storage UV-C treatment, followed by storage at low level of ethylene improves the quality of limes, with the additional improvement when combined with 1-MCP treatment prior or after UV-C irradiation.

VACUUM INFILTRATION OF 24-EPIBRASSINOLIDE DELAYS CHLOROPHYLL DEGRADATION AND MAINTAINS QUALITY OF LIME DURING COLD STORAGE

Effects of 24-epibrassinolide (EBR) treatments on chlorophyll (Chl) degradation and postharvest quality of two lime (‘Persian lime’ and ‘Tahiti’) cultivars during chilling-induced storage were studied in this work. EBR at 0, 2.5, 5 and 10 µM were applied to fruit by vacuum infiltration at 30.63 kPa for 7 min and afterward stored at 4°C for 60 days. Postharvest EBR application effectively maintained greater fruit firmness and lessened weight loss during cold storage. The results displayed that EBR treatments efficiently delayed the reduction of the Chl a contents and hue values. EBR treatments significantly increased ascorbic acid content, total phenolic content (TPC), antioxidant activity, and titratable acidity (TA). On the other hand, the treatments reduced soluble solids concentration (SSC), pH, and SSC/TA ratios during cold storage. Overall, EBR application by vacuum infiltration could be an effective and simple method for maintaining postharvest quality of limes during cold storage.

Application of Improved BP Neural Network in Hybrid Control Model of Lime Quality

Abstract In this paper, a method of combining neural network with expert system is proposed, which can realize the control model of real time feedback and control parameters. The model is based on the parameters of production condition, and the current lime quality is predicted. Through the quality of lime and control parameters, using association rule base of expert system, reasoning that lime control parameter adjustment, timely feedback to the lime production control system, to achieve the purpose of real-time control of the quality of lime. The paper presents application of improved BP neural network in hybrid control model of lime quality.

The Effect of Postharvest UV-C Treatment and Associated with Different Storage Conditions on the Quality of Tahitian Limes (Citrus latifolia)

Tahitian limes (Citrus latifolia) were exposed to 0 and 7.2 kJm-2 UV-C. After treatments, it was stored for 28 days in air at 20°C, 80% RH (control) and in air containing <0.005 or 0.1 μL.L−1 ethylene at 20°C and 100% RH. Weight loss, peel colour, calyx abscission, ethylene production, respiration rate, soluble solids content (SSC), titratable acidity (TA) and acceptability index were assessed. The UV-C light treatment significantly affected the quality of lime during storage. UV-C treatment significantly affected peel degreening at 20°C in all storage conditions, whereas treated limes showed significantly lower in peel degreening than the control. These effects reduced over the storage time, with the exception of fruits stored in <0.005 μL.L-1 ethylene which still produced a significantly higher in Hue value after 21 days storage relative to the control. UV-C treatment affected ethylene production during storage under all storage conditions. This effect also diminished with storage time. UV-C treatment did not affect the respiration rate, SSC or TA for all storage conditions. The UV-C treated limes had higher acceptability index than untreated limes up to 14 days storage at 20°C. Storage conditions significantly affected ethylene production, with limes that stored in air exhibiting higher ethylene production than fruits stored in the <0.005 or 0.1 μL.L-1 ethylene atmosphere. Storage conditions also significantly affected weight loss, with fruits stored in air showing greater weight loss compared to the other storage conditions. The results suggest that a pre-storage UV-C treatment, followed by storage in less than 0.1 μL.L-1 ethylene atmosphere improves the quality of limes postharvest.

Characterization of Dolomitic Lime as the Base Reagent for Precipitation of Mg(OH)2 from Seawater

The process of obtaining magnesium hydroxide from seawater involves precipitation of magnesium ions with suitable basic reagents, such as calcined dolomite. The purity of the magnesium hydroxide precipitate depends on dolomite characteristics; therefore, it is necessary to find high purity dolomite with good physical properties. The aim of this study was to characterize the specific dolomite from the location of Đipalo-Sinj (Croatia), its quality, and the favourable conditions for calcination. Certain physical and chemical characteristics were determined by pure chemical analysis, as well as by using TG/DTG-DTA, FTIR and SEM/EDS analysis. Good chemical quality of dolomitic lime (59.03 wt. % CaO, and 40.69 wt. % MgO) with low content of impurities was confirmed with the TG/DTG-DTA thermal analysis. In the atmosphere of air + CO 2 , dolomite decomposes to CaCO 3 and MgO in a temperature area between 415 and 824 °C; thereafter, another reaction begins – the decomposition reaction of calcium carbonate, completed at 897 °C. In air, the simultaneous decomposition of two carbonates occurs between 657 – 840 °C. The FTIR and EDS analyses confirmed the complete breakdown of carbonates at 950 °C. The main components (Mg, Ca, and O) confirmed the purity of the dolomite lime.

Effect of nitric oxide on postharvest quality of lime fruit (citrus aurantifolia swingle)

The effect of different concentrations of nitric oxide (NO) on postharvest life of lime (Citrus aurantifolia Swingle) was investigated. Lime was immersed with nitric acid at concentration 0, 5, 10 and 20 µg /l for 1 minute then kept at 4 C°. Changes in weight loss, total soluble solids (TSS), fruit firmness, ascorbic acid (vitamin C), and Chlorophyllase activity were evaluated periodically with 7 day intervals during storage. The results showed that lime immersed with 5µg/l SNP was significantly delayed the decrease of weight loss and firmness, also maintained the highest ascorbic acid and delayed the increase of total soluble solids contents during storage. Moreover, lime fruits treated with 20 ug/l SNP increased more slowly Chlorophyllase activity than the other treatments. This application of NO may be a useful method for extending shelf-life and maintaining quality of lime.

Effect of plant growth regulators and chemicals on yield and quality of acid lime (Citrus aurantifoliaSwingle) under foothill condition of Arunachal Pradesh

An experiment to study the effect of plant growth regulators and chemicals on acid lime (Citrus aurantifolia Swingle) was carried out in the year 2014 in the Experimental Farm, Department of Fruit Science, College of Horticulture and Forestry, Central Agricultural University, Pasighat, Arunachal Pradesh. The experiment was laid out in Randomized Block Design with eight treatments and three replications. The treatments were T1 (control-water spray), T2 (GA 50 ppm), T3 (GA 100 ppm), T4 (Cycocel 1000 ppm), T5 (KNO3 one percent), T6 (GA3 50 ppm + Cycocel 1000ppm), T7 (GA3 100 ppm + Cycocel 1000 ppm), T8 (GA3 100 + Cycocel 1000ppm +KNO3 1 per cent. The experimental results indicate that the acid lime trees sprayed with GA3 100 ppm + Cycocel 1000ppm + KNO3 1 per cent showed better performance in delaying of flowering, increase the number of flower/shoot (6.62), number of fruits/tree (149) and average fruit yield (4.64 kg/tree) of the crop. Effect of growth regulators and chemicals on quality characters however was not found significant for most of the parameters except TSS, ascorbic acid and titrable acidity. The higher results were obtained in T8 i.e. GA3 100 ppm + Cycocel 1000ppm + KNO3 1 per cent (8.27%) for titrable acidity and ascorbic acid (41.21 mg). Control with water spray alone registered the lowest values for both quantitative and qualititative parameters.

Carnauba Wax and Modified Atmosphere in Refrigerated Preservation of ‘Tahiti’ Acid Limes

Peel yellowing and loss of fruit mass reduce the useful life of acid limes and limit their commercialization. The goal of the present study was to prolong the post-harvest preservation of acid limes using wax and packaging. Fruits were harvested, selected, disinfected, treated with fungicide, coated with Carnauba wax and placed in cardboard boxes wrapped with different plastic packaging. A fruit lot treated only with wax coating was used as a control. The fruits were stored at 10°C for 24 days followed by 6 days at 20°C. The gas atmosphere inside the packages was analysed during storage. The loss of mass, color index, titratable acidity, and total chlorophyll, ascorbic acid, soluble solids, acetaldehyde and ethanol concentrations of the fruits were measured. The combined use of wax coating and plastic Cryovac® D-955 (Cryovac Brasil Ltda, São Paulo, Brazil) and Vegetal Pack® (Eletropolimeros do Brasil Ltda, São Paulo, Brazil) films resulted in better post-harvest preservation of acid limes compared with only wax coating because the combined treatment maintained the green peel color following 30 days of storage in addition to resulting in lower loss of mass and maintaining chemical characteristics adequate for commercialization. The LDPE (low density polyethylene) and Xtend® packaging (Stepac Brasil Ltda, São Paulo, Brazil), although they prevented peel degreening, did not result in an adequate atmosphere to maintain the quality of limes due to the accumulation of high concentrations of acetaldehyde and ethanol, especially for the LDPE packaging. LDPE drastically changed the atmosphere surrounding the fruit, resulting in loss of the characteristic pulp color, in addition to conferring an alcohol odor. Copyright © 2015 John Wiley & Sons, Ltd.

On heat exchange - burning conditions relation in manufacturing lime in a rotary kiln

The work objective is to study the effect of the temperature lime burning conditions in a rotary kiln on the quality indices of the industrial lime used in the steelmaking. The methodology for studying the heat transfer conditions and the temperature behavior of the bulk material under the heat passage and temperature-waves propagation in the semibounded space of a rotary kiln is offered. It is shown that a system of equations describing boundary conditions of the limestone heating by the radiant heat flux becomes increasingly complicated in the case of the parallel convective heat transfer. To simplify the calculations, it is suggested to reduce the combined radiant and convective heat transfer to the convective one (in form) using the known criterial dependences. The investigation results of the heat transfer in the ‘flame - limestone’ system with testing apparent and optimum temperatures in the burning zone are presented. The thermal effect in the rotary kiln on the lime quality indices is specified experimentally under the laboratory and plant conditions. Conditioning of the slag adjustment by the lime consumption during the steel electrosmelting in an arc furnace is defined. Conclusions on the effect of the furnace thermal performance on the principle processes of the carbonate raw materials kilning in the industrial lime manufacturing are formulated. The optimal furnace temperature conditions for manufacturing quality lime with more than 90% CaO are specified.

EFFECT OF TEMPERATURE MODE OF LIMESTONE CALCINATIONIN A ROTARY FURNACE ON LIME QUALITY

The influence of the temperature mode in the rotary furnace on lime quality is established experimentally in laboratory and industrial conditions with its impact on the slag mode during electric smelting of steel in electric arc furnaces.

Mill study on improving lime kiln efficiency

Optimization of the lime kiln requires an examination of the entire lime cycle. To increase the energy efficiency of the lime kiln, all auxiliary unit operations must function properly. It is also imperative that the lime and liquor in the system is of acceptable quality. We detail a kiln energy efficiency study performed by MWV Corp.’s Covington, VA, USA, mill. From a recausticizing standpoint, lime quality is much easier to control than liquor quality because liquor passes through many operations that are not under the lime kiln operator’s control. Recausticizing is a fairly closed cyclical process where lime is concerned, so saturation of impurities to the point of operational issues must be considered. Specific cycle performance indicators (e.g., lime mud solids entering the kiln) must be viewed from a perspective that does not exclude their potential impact. To get a true picture of the cost of operating the lime cycle, all inputs must be considered. The four main inputs are power (electrical and fuel), fresh lime, caustic, and water.

Limestone calcination optimization of vertical container oven

Producing lime demand high energy consumption and implies high CO2 emissions and other environmental impacts significant. This work aims to establish a methodology for optimizing the calcination of limestone kilns normal vertical Cuba, to consider the influence of the quality of lime on the economic contribution margin. In this case they are used as tools work the method of exergy analysis and the method of genetic algorithms was used. The exergy balance limestone calcination identified that irreversibilities of combustion and heat transfer time and exergy loss in the exhaust gases, are the principal process inefficiencies. The implementation of the proposed optimization methodology reduced the energy consumption by 4.6% and increased the quality of lime at 5.3%.

Production of low-sulfur steel with limited hydrogen content

The converter production of steel with low sulfur content is analyzed. Existing desulfurization methods greatly increase the hydrogen content in the steel. Options for reducing the hydrogen content associated with the solid slag-forming mixture are outlined. The influence of the storage time and conditions on the quality of fluidized lime and correspondingly on the steel’s hydrogen content is discussed.

Study of the Use of Lime Plaster on Heritage Buildings’ in Malaysia: A Case Study in George Town, Penang

Awareness of the use of compatible materials in historical building conservation has resulted in a rebirth of lime technology and application. However, knowledge of the preparation of and procedures influencing the final quality of lime is still limited and disagreement regarding the proper use of lime in heritage building conservation still continues to exist. The purpose of this paper is to highlight the reasons for deterioration and to suggest possible treatments for external walls of heritage buildings in George Town, Penang. Since lime has been used on most external walls, it was chosen as the focus of this research. This study was conducted based on a qualitative method which drew upon a review of literature, visual observations, and interviews. From a pilot survey of 85 historical buildings in the core zone, it was found that from the use of lime based materials, the possible defects were caused by three factors: climatic change, air pollution, and maintenance issues. This study focuses on the use of lime plaster as well as issues that could arise from its improper use.

Properties of lignin extracted from sugarcane bagasse and its efficacy in maintaining postharvest quality of limes during storage

Lignin extracts from sugarcane bagasse by alkaline extraction in the presence and absence of ethanol were investigated for their efficacy on maintaining fresh fruit shelf life. For lignin extraction, the highest lignin yield was obtained from 40% (w/w) NaOH extraction in water. Addition of ethanol gave relatively lower yield of lignin but less hemicellulose contamination. FT-IR intensity of lignin-to-carbohydrate transmittance ratios of extracted lignin from 40% (w/w) NaOH in distilled water were similar to the ratios of lignin standard from Kraft process. From gel permeation chromatography (GPC), lignin isolated from 40% (w/w) NaOH in distilled water yielded high amount of both large and small molecules of lignin. The weight loss ratio between lignin and hemicellulose was analyzed by thermogravimetric analysis (TGA). It was confirmed that isolated lignin from 40% (w/w) NaOH in distilled water contained highest amount of hemicellulose in lignin extract. The test of coating formulas on limes demonstrated that coating solutions of 0.8% (w/w) xanthan gum and 1.5% (w/w) extracted lignin from 40% (w/w) NaOH had potential to maintain weight loss and color change. This coating formula also exhibited higher antifungal activities. Limes coated with extracted lignin showed higher antifungal activity than limes coated with commercial lignin.

Effects of Unburned Lime on Soil pH and Base Cations in Acidic Soil

Sustainable agriculture is threatened by the widespread soil acidity in many arable lands of Rwanda. The aim of this study was to determine the quality of unburned limes and their effects on soil acidity and base cations in acidic soils of high land of Buberuka. The lime materials used were agricultural burned lime and three unburned lime materials, Karongi, Musanze, and Rusizi. The test crop was Irish Potato. All lime materials were analyzed for Calcium Carbonate Equivalent (CCE) and Fineness. A field trial in Randomized Complete Block Design was established in 2011 at Rwerere research station. The treatments comprised of the four lime materials applied at four levels: 0, 1.4, 2.8, and 4.3 t ha−1 of CCE. Soil cations (Ca2+, Mg2+, K+, and Na+) were determined by extraction method using atomic absorption spectrophotometer for Ca and Mg and flame photometer for K and Na. The Al3+ was determined using potassium chloride extraction method. Experimental soil baseline showed that the soil was very strongly acidic (2.8 cmol kg−1 Al3+). The unburned limes were significantly (P&lt;0.001) different in terms of CCE and fineness. A higher CCE was recorded in agricultural burned and Rusizi unburned limes (86.36% and 85.46%, resp.). In terms of fineness, agricultural burned and Musanze unburned lime were higher (70.57 and 63.03%, resp.). Soil acidity significantly affected from 4.8 to 5.6 pH and exchangeable Al reduced from 2.8 cmol kg−1 to 0.16 cmol kg−1 of Al3+. Similarly all cations affected by unburned limes application, significantly (P&lt;0.001) Ca saturation increased from 27.44 to 71.81%, Mg saturation from 11.18 to 36.87% and significantly (P&lt;0.001) Al saturation reduced from 58.45 to 3.89%. The increase of Mg saturation was observed only with Karongi unburned lime application. This study recommends therefore, the use of 2.8 t ha−1 of CaCO3 of Rusizi or Musanze unburned lime as alternative to the agricultural burned lime for improving soil acidity and base cations in acidic soils.

English

Soil erosion, soil nutrient depletion and soil acidity associated to Aluminium (Al) toxicities are the main soil related constraints to agricultural development in many countries of sub-Sahara Africa. The lime plays an important role in improving soil acidity and hence favours plant nutrition. The aim of this study was to map out the available limestone deposits and to determine their selected quality. The selected quality of limestone (CaO, MgO and fineness factor) was analyzed using ethylene diamine tetraacetate (EDTA) method. The global positioning system (GPS) coordinates of limestone deposits were taken. The collected data were processed using Arc GIS 9. The fineness factor was determined by mechanically sieving the lime through a stag of 4 sieves of various aperture dimensions (2, 1, 0.5 and 0.2 mm). The map showed that the limestone deposits are scattered in Northern and Western provinces with more concentration in Northern region. Mpenge limestone had an average of 40% ±4.2 of CaO and 3% ±0.9 of MgO. However, its fineness factor of 63% ±2.01 found to be in good range. Gishyita deposit was heterogeneous in CaCO3, its CaO was 50% ± 20.02 indicating high variability within mines where CaO reached < 30%. Mashyuza deposit in Rusizi region had 50% ±3.4 of CaO and moderate MgO of 3% ±0.6. However, its fineness factor was 55.6% ±1.6 .The difference in lime quality observed in this study was possibly due to the origin of limestone rocks. However, the fineness factors were below the acceptable level because of non-additional grinding and lack of technological skills in producing lime. Therefore, this study recommends the use of grounded limestone after fine grinding. Key words: Limestone deposit sites, CaO, MgO, fineness factor.

The Tests on the Lime-Treated Expansive Soils Compaction Characteristics

The compaction characteristics of the lime-treated expansive soils from the planning airport in China's Ankang were studied through the heavy compaction tests. The results show that all these elements such as lime content, water content, soil height, wetting time have a certain effect on dry density. As the lime quality ratio increases, the optimum water content under heavy compacting standard of improved soils increases but the maximum dry density decreases. With the increase of lime content, the effect of water content on dry density decreases while the water content near to its optimum value. Soils with the lower height have higher dry density when compaction energy, lime content and water content unchanged. As the wetting time increases, the maximum dry density shows a decreasing tendency until after 48 h it remained stable. It indicates that with the same lime content the order of primary factors influence on dry density are water content, wetting time, soil height. Finally, the lime stabilizing principle to expansive soil is explained through by applying scanning electron microscope technique.

Availability of Trace Elements for Chinese Cabbage Amended with Lime in a Periurban Market Garden in Yunnan Province, China

Pot experiments were conducted in the laboratory with lime applications to decrease trace elements in Chinese cabbage produced on soils contaminated by trace elements in the intensive periurban area in Chenggong County, Yunnan Province, China. Soil was an acidic loam developed from lacustrine-alluvial deposits. Results showed the following: (1) soil pH increased from 5.3 to 6.5, and acetic-acid-extractable trace-element contents and ratio of acetic-acid-extractable trace-element contents in treatments relative to those in the control (RRCT) decreased with increased rate of lime application. (2) Chinese cabbage more easily absorbed acetic-acid-extractable trace elements. Enrichment coefficients related to trace-element availability (AEC) of lead (Pb; mean: 3.3) and zinc (Zn; mean: 5.8) were stable, and the AEC of cadmium (Cd) was 1.8–2.0 with increased lime application rate. (3) Trace-element contents in Chinese cabbage decreased, and biomass of Chinese cabbage increased, with lime application rate. Trace-element contents in soil solution and acetic-acid-extractable trace-element contents can predict trace-element contents in Chinese cabbage, especially for soil solution. Lime quality and trace-element accumulation in Chinese cabbage should be taken into account when amendment is added to in situ soil contaminated with trace elements.

INFLUENCE OF CONTROLLED ATMOSPHERE ON THE QUALITY AND STORAGE LIFE OF LIME (CITRUS AURANTIFOLIA 'PAAN')

The effects of controlled atmosphere (5%, 10% O 2 and 1%, 5% CO 2 ) on the quality and storage life of lime was determined. A low concentration of O 2 (5% O 2 ) combined with high CO 2 (1% and 5% CO 2 ) had a storage life of 7 and 4 weeks, respectively. Combination of 10% O 2 with 1% and 5% CO 2 had a storage life of 8 and 6 weeks, respectively, while as under air condition at 10°C had a storage life of 5 weeks. Lime exposed at ambient temperature had a storage life of only 2 weeks. Color L value tends to increase in association with turning to yellow of lime during storage. Exposure to 1% CO 2 +10% O 2 condition delayed chroma value increasing and delayed hue value decreasing more than other treatments. Exposure to low O 2 and high CO 2 did not affect titratable acidity (TA) and soluble solid (SS) contents. Vitamin C content of all treatments did not change in 5 weeks during storage but after that vitamin C content rapidly decreased until the end of storage.