Problems of Autoclaved Aerated Concrete Treatment

2018 ◽  
Vol 284 ◽  
pp. 1069-1073
Author(s):  
A.A. Vishnevskiy ◽  
F.L. Kapustin
Keyword(s):  
Heat Transfer ◽  
Pressure Rise ◽  
Chemical Processes ◽  
Porous Space ◽  
Cold Air ◽  
Warm Up ◽  
Physical Chemical ◽  
Aerated Concrete ◽  
Cellular Concrete

The problems of autoclave c of cellular concrete are considered. It was shown that the key problem of autoclaving is the appearance of areas of concrete with different dark colors and a reduced strength. The main reason for their occurrence is the presence of air in the porous space of cellular concrete, which prevents heat transfer. Cold air does not allow the concrete to warm up to a temperature of 170-175 °C, which hinders the flow of physical-chemical processes of hardening. The proposed activities that improve the quality of autoclave processing and precluding the formation of «non-steamings» in the concrete: ensure the temperature inside cellular concrete mass of at least 80 °C before curing, the vacuum (P=‒0.5 Bar) before pressure rise in the autoclave, preventing the ingress of air into the autoclave at the beginning of the process.

scholarly journals Influencia De la Madurez de las Mazorcas de Cacao: Calidad Nutricional y Sensorial del Cultivar CCN-51

2021 ◽  
Vol 6 (2) ◽  
pp. 27
Author(s):  
Jonathan Bladimir Zhiminaicela Cabrera ◽  
Cristhel Mora Encalada ◽  
José Quevedo Guerrero ◽  
Sayda Herrera Reyes ◽  
Anthony Morocho Castillo ◽  
...  
Keyword(s):  
Theobroma Cacao ◽  
Sensory Quality ◽  
Chemical Processes ◽  
Nutritional Content ◽  
Post Harvest ◽  
Physical Chemical ◽  
Spss Software ◽  
Theobroma Cacao L ◽  
One Way Anova

  El chocolate producto derivado del procesamiento de semillas de cacao (Theobroma cacao L.) es considerado como un alimento de lujo en el mercado internacional, apetecido especialmente por el sabor, aroma y los beneficios para la salud del consumidor, siendo el contenido nutricional y la calidad sensorial los principales indicadores de competitividad. El desarrollo fisiológico de las mazorcas influye en los procesos físico-químicos de la etapa postcosecha de donde se forma el aroma y sabor. Por esta razón, el objetivo de la investigación fue determinar la influencia de seis estados de madurez de mazorcas de T. cacao L. cultivar CCN-51, en la fermentación, calidad nutricional y sensorial del licor de cacao, evaluadas en dos tiempos postcosecha: fermentadas-secas y torrefacción. Se realizaron pruebas físico-químicas, análisis químico proximal y análisis sensorial del licor de cacao. Los datos se analizaron con el software SPSS con una prueba de ANOVA de una vía y la prueba de Tukey al 0,05%. Los resultados presentaron diferencias significativas (p < 0.05) en el índice de fermentación del estado 5 (98%) con respecto al 0 (18%), estos resultados se relacionaron con la calidad nutricional y sensorial. La madurez de las mazorcas influyó en el contenido nutrimental en las etapas postcosecha estudiadas, así las mazorcas inmaduras redujeron el índice de fermentación de las semillas afectando la calidad sensorial del licor de cacao.   Palabra clave: Manejo postcosecha, fermentación, torrefacción, madurez fisiológica, propiedades fisicoquímicas.   Abstract Chocolate, a product derived from the processing of cacao beans (Theobroma cacao L.), is considered a luxury food on the international market, especially sought after for its taste, aroma, and health benefits for the consumer. The nutritional content and sensory quality are the main indicators of competitiveness. The physiological development of the cobs influences the physic-chemical processes of the post-harvest stage where aroma and flavour are formed. For this reason, the objective of the research was to determine the influence of six stages of maturity of the cocoa pods of T. cacao L. cultivar CCN-51 on the fermentation, nutritional and sensory quality of cocoa liquor. Evaluated in two post-harvest stages: fermented-dried and roasting. Physical-chemical tests, proximal chemical analysis, and sensory analysis of the cocoa liquor were carried out. Data were analysed using SPSS software with a one-way ANOVA test and Tukey's test at 0.05%. The results showed significant differences (p < 0.05) in the fermentation index of stage 5 (98%) with respect to stage 0 (18%), these results were related to nutritional and sensory quality. The maturity of the pods influenced the nutritional content in the post-harvest stages studied, so the immature pods reduced the fermentation rate of the beans, affecting the sensory quality of the cocoa liquor.  Keywords: Post-harvest handling, fermentation, roasting, physiological maturity, physicochemical properties.

Electrical Damage Due to Low Energy Plasma Processing of GaAs Structures

1991 ◽  
Vol 223 ◽  
Author(s):  
Hans P. Zappe ◽  
Gudrun Kaufel
Keyword(s):  
Chemical Processes ◽  
Low Energy ◽  
Electrical Behavior ◽  
Rapid Thermal Anneal ◽  
High Temperature Anneal ◽  
Significant Damage ◽  
Low Energies ◽  
Long Time ◽  
Physical Plasma

ABSTRACTThe effect of numerous plasma reative ion etch and physical milling processes on the electrical behavior of GaAs bulk substrates has been investigated by means of electric microwave absorption. It was seen that plasma treatments at quite low energies may significantly affect the electrical quality of the etched semiconductor. Predominantly physical plasma etchants (Ar) were seen to create significant damage at very low energies. Chemical processes (involving Cl or F), while somewhat less pernicious, also gave rise to electrical substrate damage, the effect greater for hydrogenic ambients. Whereas rapid thermal anneal treatments tend to worsen the electrical integrity, some substrates respond positively to long-time high temperature anneal steps.

Heat Transfer Enhancement in Separation Process of Ethanol from Ethanol Water Mixture by Using Surfactants

2020 ◽  
pp. 9-14 ◽  
Author(s):  
Acharya Anil Ramchandra ◽  
R. Kadam ◽  
A. T. Pise
Keyword(s):  
Heat Transfer ◽  
Ammonium Chloride ◽  
Sodium Dodecyl ◽  
Water Mixture ◽  
Transfer Enhancement ◽  
Surface Tension Reduction ◽  
Surface Active Agents ◽  
Surface Active ◽  
Time Required

Here the investigations are done while distillation of ethanol-water mixture for separating ethanol from fermentation process. Focus is to study reduction in time required and hence saving in energy for the distillation process of ethanol-water mixture under the influence of surface-active agents (Surfactants). This novelty is from observation of these surfactants to enhance heat transfer rate because of surface tension reduction in aqueous solutions. SDS (Sodium Dodecyl Sulphate), NH4Cl (Ammonium Chloride) and SLBS (Sodium lauryl benzene sulphonate) surfactants in different concentration are experimented. The concentration of these surfactant is varied from 1700 ppm to 2800 ppm. This range is decided by observing critical micelle concentration of used surfactants. Results showed that time is reduced and hence energy consumption is also reduced. Results shown by NH4Cl are found to be more useful as it is ecofriendly surfactant which is not affecting ethanol-water mixture. Use of ammonium chloride as surfactant in distillation is actually useful to reduce energy without hampering the quality of process is the novelty of this work.

The real concept of substitution in Ayurveda literature and adulteration the misleading concept of modern era

2018 ◽  
Vol 3 (3) ◽  
Author(s):  
Ashashri Shinde ◽  
Pankaj Gupta ◽  
Sudipt Rath
Keyword(s):  
Medicinal Plant ◽  
Plant Material ◽  
Genetic Parameters ◽  
Herbal Drugs ◽  
Material Identification ◽  
The Real ◽  
Physical Chemical ◽  
Unfair Trade ◽  
Modern Era

A quality drug is central to the success of any therapeutic plan. The quality of drug is determined right from the collection to delivery to the patients. The commonest problem involving the medicinal plant stating materials is intentional or unintentional substitution and adulteration owing to multiple reasons like unavailability, higher costs, unfair trade etc. This trend was also present in the olden days, as evident from the concept of substitute drugs (Pratinidhi Dravya) as available in Yogratanakara, Bhavaprakasha and Bhaishajyaratnawali. Therefore, Charka and later Acharyas also have dealt with authentication and standardization of herbal drugs and formulations in detail by using four Pramanas (tools of knowledge) Ch.Vi.8/87. Nowadays the concept of substitution is entirely converted into intentional and unintentional malpractices of adulteration. The established authenticity parameters for plant material identification and standardization like organoleptic, physical, chemical and genetic parameters are relatively inaccessible for routine use. Not withstanding the accuracy and usefulness of these lab parameters and delay in the development of easy to perform parameters for reasonable drug authentication. These adulteration malpractices spoils the market of herbal industries. In this article we discuss about concept of substitution in ancient Ayurveda and at present intentional and unintentional adulteration practices.

Evaluation of the microbiological and physical-chemical quality of salted bovine meat marketed in establishments and free fairs in the north zone of Rio de Janeiro

2018 ◽  
Vol 6 (4) ◽  
pp. 65
Author(s):  
Julio Cesar Queiroz Penha ◽  
Robson Maia Franco ◽  
Maria Carmela Kasnowski Holanda Duarte ◽  
Katia Christina Leandro
Keyword(s):  
Rio De Janeiro ◽  
Chemical Quality ◽  
The North ◽  
Physical Chemical

scholarly journals Adjustment of Olive Fruit Temperature before Grinding for Olive Oil Extraction. Experimental Study and Pilot Plant Trials

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 586
Author(s):  
Eddy Plasquy ◽  
José María García Martos ◽  
María del Carmen Florido Fernández ◽  
Rafael Rubén Sola-Guirado ◽  
Juan Francisco García Martín
Keyword(s):  
Heat Treatment ◽  
Pilot Plant ◽  
Heating System ◽  
Oil Extraction ◽  
Warm Up ◽  
Precise Adjustment ◽  
Olive Cultivars ◽  
Plant Trials ◽  
Washing Water

Harvesting at high temperatures and bulk transport can negatively influence the quality of olives and lead to undesirable alterations in the extracted oil. Cooling the fruit in the field would be the most logical solution, but it means that the olives arrive too cold at the mill for immediate processing. In this work, the use of warm water in the washing tub to warm up the fruit before grinding instead of flash heat treatment on the paste was assessed in two experiments. In the first one, at the laboratory level, the temperature after milling was determined in three olive cultivars, previously stored at 5 or 10 °C, and then submerged at different water temperatures (25, 30, and 35 °C) for 15, 30, 45, and 60 s. In the second one, two batches of olives were cooled in the field at 5 °C and then conditioned with washing water to obtain a paste at the entrance of the pilot plant malaxer at 27 °C. The temperature of the olives was measured at five points from the discharging up to their entering, as paste, into the malaxer. The results demonstrated the feasibility of the method as the temperature of the ground olives was kept at the desired temperature (28 ± 1 °C). The trials highlight the potential for automating an even more precise adjustment of the temperature of the olives before milling once the washing tub is equipped with a safe heating system.

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