Microwave Vacuum Drying Effect on Peanut Quality1

1986 ◽  
Vol 13 (1) ◽  
pp. 21-27 ◽  
Author(s):  
S. R. Delwiche ◽  
W. L. Shupe ◽  
J. L. Pearson ◽  
T. H. Sanders ◽  
D. M. Wilson
Keyword(s):  
Latin Square ◽  
Microwave Treatment ◽  
Microwave Drying ◽  
Treatment Level ◽  
Planting Dates ◽  
Microwave Vacuum Drying ◽  
Arachis Hypogaea L ◽  
Treatment Type ◽  
Processing Order ◽  
Microwave Process

Abstract Florunner peanuts (Arachis hypogaea L.) were grown during the 1984 season near Tifton, Georgia. Two planting dates spaced one month apart were used to obtain four weekly digging dates. Peanuts from each harvest were windrow dried for 4 days, mechanically harvested and placed into a ventilated wagon for 1 to 4 days. Peanuts were subsequently removed from the wagon, shelled at 8 to 22% moisture (wb), and microwave vacuum dried at nominal rates of 4, 8, 16, and 32 times the normal rate of conventional wagon drying. Harvest group, microwave treatment level, and order of processing were configured in a Latin Square design. Concurrent with each microwave run (MV), a separate portion of the shelled peanuts was deep bed dried (CS) and another portion was similarly dried but within shell (CH). Analyses of variance were performed to determine the significance of treatment type, microwave level, harvest group, and processing order differences on splitting and skin slippage tendencies, mold growth, and germination potential. No significant (p> .05) differences were observed among treatment types for splitting and skin slippage potential, though slight (p< .05) differences existed among microwave treatment levels (damage increasing with increasing microwave drying rate), and drying order within microwave treatment (damage decreasing with increasing drying order). Larger (p< .01) splitting and skin slippage differences existed among harvest groups. MV treatments had significantly (p< .01) higher presence of A. flavus than the CS and CH treatments though aflatoxin was not detected in any sample. The percentage of normal strong germinated kernels from MV treatments was significantly (p<.01) lower than from the CS and CH treatments, with germination decreasing with increasing microwave process rate.

A New Way to Uniform Microwave Treatment of Epoxy Glass

2015 ◽  
Vol 813 ◽  
pp. 265-272
Author(s):  
Wei Wei Du ◽  
Lyes Douadji ◽  
Fethi Benkhenafou ◽  
Hong He ◽  
Cheng Li
Keyword(s):  
Electromagnetic Waves ◽  
Microwave Treatment ◽  
Microwave Processing ◽  
Leaf Spring ◽  
Microwave Source ◽  
Electromagnetic Modelling ◽  
Dielectric Effect ◽  
Microwave Heat ◽  
Uniform Treatment ◽  
Microwave Process

This work is part of an ambitious project aiming to manufacture epoxy-glass leaf spring by microwave processing. Physical properties of final products to be manufactured, in particular the mechanical properties, are directly dependent on uniform repartition of microwave source heating during the treatment. The major problem in microwave processing, however, is attenuation of microwave source. We propose Dielectric Effect of Attenuation Inversion of the Electromagnetic Waves (DEAI) as a new way for uniform treatment of epoxy glassmicrowave energy. This solution utilizes dielectric properties of the mold to control the microwave heat source attenuation into the composite to be treated. Electromagnetic modelling of microwave process was carried out and validated by experimental results. The results show that microwave source heating attenuation can be controlled and inversed. We demonstrated uniform treatment on epoxy-glass parts ca. 100 cm long by means of compensation of microwave source attenuation.

scholarly journals MICROWAVE TREATMENT OF MATERIALS IN LOW PRESSURE

2019 ◽  
Author(s):  
Parosa Ryszard ◽  
Andrzej Brożyński ◽  
Piotr Grześkowiak ◽  
Krzysztof Kowalczyk ◽  
Marek Natoński ◽  
...  
Keyword(s):  
Treatment Time ◽  
Low Pressure ◽  
Microwave Treatment ◽  
Laboratory Scale ◽  
Microwave Drying ◽  
Microwave Cavity ◽  
Industrial Scale ◽  
Heating Process ◽  
Universal System ◽  
Scale Unit

Ryszard Parosa, Andrzej Brożyński, Piotr Grześkowiak, Krzysztof Kowalczyk, Marek Natoński, Piotr Ziętek and Janusz Żytkiewicz PROMIS-TECH Poland Keywords: microwave treatment, low pressure heating, microwave drying Uniquely favourable characteristics of biological product can be obtained through the use of the microwave method in vacuum heating process. Microwave-vacuum drying is superior to other methods in terms of dried products' structure, flavour, colour and biological active compounds contents. But applications of such a methods seems to be much wider: drying of fruits and vegetables for consumption, drying of herbs for extraction of valuable biological compounds, for modification of seed structure (sunflowers seeds, pumpkin seeds), for pasteurisation etc. A universal system was designed for testing such processes in laboratory scale and several industrial scale system have been developed. Process of thermal treatment can be carried out with plastic drum installed inside of multi-mode microwave cavity and cavity which is connected by microwave line with reflectometer and circulator - to microwave generator. In laboratory unit generator 2.45 GHz with controlled power (from 50W to 800W) was applied. System was equipped with vacuum pump with pressure control and is controlled by computer. Most important technical parameters, like: microwave power, time of treatment, pressure inside of drum, temperature of steam – are controlled and  recorded. Laboratory scale unit is shown below.     Basing on laboratory scale test several technologies in industrial scale was developed. Industrial scale unit equipped with 8 generators of 3 kW (2.45 GHz) was constructed and for last 8 years has been successfully used for “production” of crispy chips which are now popular in Polish marked. Exemplary industrial scale installation is shown in photo below.  Multi – drum microwave drier.   Two cavity microwave  industrial drier    Another system for modification od seed is now constructed – ordered by big industrial producer of batons and sweet snacks. Process will be carried our inside of dielectric drum in low pressure and reactor will be equipped with 8 generators of 3 kW (2.45 GHz). Treatment time will be reduced to 3-4 minutes and next material (seeds) will be cooled down. Last project which now realized is connected with drying of wood flour applied in composite material production. System will work continuously with two airlocks and with  dielectric drum and will be connected with 4 microwave generators (3 kW, 2.45 GHz). In next step planed installation will be equipped with microwave high power generator ca. 60 kW with frequency 915 MHz. 

scholarly journals A Smart Screening Device for Patients with Mental Health Problems in Primary Health Care: Development and Pilot Study

2018 ◽  
Vol 5 (2) ◽  
pp. e41 ◽  
Author(s):  
Jan van Bebber ◽  
Rob R Meijer ◽  
Johana TW Wigman ◽  
Sjoerd Sytema ◽  
Lex Wunderink
Keyword(s):  
Mental Health ◽  
Mental Health Problems ◽  
Well Being ◽  
Health Problems ◽  
Domain Score ◽  
Test Administration ◽  
Treatment Level ◽  
Computerized Adaptive Test ◽  
Final Treatment ◽  
Treatment Type

Background Adequate recognition of mental health problems is a prerequisite for successful treatment. Although most people tend to consult their general practitioner (GP) when they first experience mental health problems, GPs are not very well equipped to screen for various forms of psychopathology to help them determine clients’ need for treatment. Objective In this paper, the development and characteristics of CATja, a computerized adaptive test battery built to facilitate triage in primary care settings, are described, and first results of its implementation are reported. Methods CATja was developed in close collaboration with GPs and mental health assistants (MHAs). During implementation, MHAs were requested to appraise clients’ rankings (N=91) on the domains to be tested and to indicate the treatment level they deemed most appropriate for clients before test administration. We compared the agreement between domain score appraisals and domain score computed by CATja and the agreement between initial (before test administration) treatment level advice and final treatment level advice. Results Agreements (Cohen kappas) between MHAs’ appraisals of clients’ scores and clients’ scores computed by CATja were mostly between .40 and .50 (Cohen kappas=.10-.20), and the agreement between “initial” treatment levels and the final treatment level advised was .65 (Cohen kappa=.55). Conclusions Using CATja, caregivers can efficiently generate summaries of their clients’ mental well-being on which decisions about treatment type and care level may be based. Further validation research is needed.

Influence of Digging Date on Yield and Gross Return of Virginia-type Peanut Cultivars in North Carolina

1998 ◽  
Vol 25 (1) ◽  
pp. 45-50 ◽  
Author(s):  
D. L. Jordan ◽  
J. F. Spears ◽  
G. A. Sullivan
Keyword(s):  
North Carolina ◽  
Field Experiments ◽  
Weather Conditions ◽  
Growing Season ◽  
Planting Dates ◽  
Pod Yield ◽  
Complex Interactions ◽  
Arachis Hypogaea L ◽  
Peanut Cultivars ◽  
Balance Complex

Abstract Peanut (Arachis hypogaea L.) growers must balance complex interactions among cultivars, planting dates, environmental and physiological stresses during the growing season, and weather conditions at harvest when determining when to dig peanut. Ten field experiments were conducted in North Carolina from 1994 through 1996 to determine the influence of digging date on pod yield and gross return of virginia-type peanut. Beginning in mid- to late September, the cultivars NC 9, NC 10C, NCV-11, VA-C 92R, AgraTech (AT) VC-1, and NC 12C were dug on four dates approximately 7 d apart. Considerable variation in pod yield and gross return was noted among cultivars and experiments. Delaying digging increased pod yield and gross return in some but not all experiments. Greater variation in pod yield and gross return was observed for NC 10C than for AT VC-1 when compared across digging dates. Pod yield and gross return for NC9, NC V-11, VA-C 92R, and NC 12C were intermediate between NC 10C and AT VC-1. Of the cultivars evaluated, yield and gross return of AT VC-1 were the most stable over digging dates. These data suggest that growers should evaluate maturity of peanut in individual fields for each cultivar when determining when to dig. These data also suggest that factors other than maturity impact pod yield and gross return.

scholarly journals Effect of Microwave Drying, Calcination and Aging of Pt/Al2O3 on Platinum Dispersion

Catalysts ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 348 ◽  
Author(s):  
Xavier Auvray ◽  
Anthony Thuault
Keyword(s):  
Microwave Heating ◽  
Single Mode ◽  
Microwave Treatment ◽  
Microwave Drying ◽  
Conventional Heating ◽  
Bet Surface Area ◽  
Great Ability ◽  
Subsequent Calcination ◽  
Platinum Dispersion ◽  
Al2o3 Catalyst

The effect of heating method employed for drying and calcination during the synthesis of 1 wt% Pt/Al2O3 catalyst was investigated. Conventional heating (CH) in resistive oven and microwave heating (MW) in single mode were applied, and the Pt dispersion and Brunauer-Emmett-Teller (BET) surface area were measured to characterize the samples. It was evidenced that the fast and homogeneous heating offered by the microwave heating led to higher Pt dispersion. However, this benefit was only achieved when the subsequent calcination was performed in a conventional oven. The aging in microwave oven of conventionally prepared—as well as MW-prepared—catalysts demonstrated the great ability of microwave irradiation to accelerate platinum sintering. After 1 h at 800 °C under microwave, catalysts showed a dispersion of 5%. Therefore, microwave treatment should be considered for accelerated catalyst aging but should be avoided as a calcination technique for the synthesis of highly dispersed Pt/Al2O3.

scholarly journals Effects of sonication and freezing on the color, mechanical and thermophysical properties of osmo-microwave-vacuum dried cranberries

2020 ◽  
Author(s):  
Izabela Anna Staniszewska ◽  
Szymon Staszyński ◽  
Magdalena Zielińska
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Diffusivity ◽  
Moisture Diffusion ◽  
Moisture Diffusivity ◽  
Microwave Drying ◽  
Vacuum Drying ◽  
Volumetric Heat Capacity ◽  
Drying Time ◽  
Microwave Vacuum Drying

The aim of study was to determine the effects of sonication (S), convective freezing (F), convective freezing preceded by sonication (SF) as well as cryogenic freezing (N) on the osmo-microwave-vacuum drying kinetics, energy usage and properties of dried cranberries such as moisture content, moisture diffusion, water activity, density, porosity, thermal conductivity, thermal diffusivity, volumetric heat capacity, lightness, redness, yellowness, total differences in color, saturation and hue, hardness, cohesiveness, springiness, and chewiness. Osmo-microwave-vacuum drying of cranberries took from 13.5 to 16.0 min. All initial treatments increased the moisture diffusivity and thus reduced the drying time. The most energy effective method was osmo-microwave-vacuum drying preceded by sonication (S) of fruits. Osmo-microwave-drying of cranberries subjected to convective freezing preceded by sonication (SF) resulted in the highest lightness (32.5 ± 0.5), redness (33.9 ± 0.7), and yellowness (11.3 ± 0.5) of fruits, as well as the lowest cohesion (the lowest resistant to stress associated with manufacturing, packaging, storage, and delivery). The lowest hardness, i.e. 12.3 ± 0.4 N and the highest cohesiveness and springiness, i.e. 0.38 ± 0.02 and 0.74 ± 0.03 of dried fruits, were noted for berries subjected to initial cryogenic freezing (N). Cryogenic freezing (N) combined with osmo-microwave-vacuum drying resulted in the largest color changes of fruits and the highest thermal conductivity. Sonicated and convectively frozen (SF) fruits were characterized by the highest thermal diffusivity. Sonication (S), convective freezing (F) and their combination (SF) significantly reduced the volumetric heat capacity of cranberry fruits.

Study on the Moisture Distribution within the Wood Treated with Microwave

2011 ◽  
Vol 327 ◽  
pp. 105-108 ◽  
Author(s):  
Jian Fang Yu ◽  
Ji Long Guo ◽  
Jing Ya Nan ◽  
Bing Hu Sun
Keyword(s):  
Relaxation Time ◽  
Bound Water ◽  
Free Water ◽  
Microwave Treatment ◽  
Moisture Distribution ◽  
Microwave Drying ◽  
Water Molecules ◽  
Saturation Point ◽  
Initial Stage ◽  
Before And After

In this paper, Siberian elm (Ulmus pumila L) which was regarded as our research object was measured with the technology of Nuclear Magnetic Resonance (NMR) before and after being treated with microwave at different periods of time. By comparing the spin - spin relaxation time of hydrogen nuclear (T2) which can reflect the mobility of water molecules, the states and changes of the moisture distribution within the wood in the process of microwave treatment have been analyzed. The results indicate that in the initial stage of drying, the degree of the decline in bound water is greater than that in free water, for there may be a process of the transformation from bound water to free water; With the drying going on, the movement and expulsion mainly happen to free water above the fiber saturation point (FSP); In the later stage of drying, when the moisture content decreases near the FSP, bound water has also begun moving significantly on the expulsion of plenty of free water. In the final stage of drying, the decrease of hydrogen bonds in water molecules resulting from a plentiful reduction in free water, as well as the increased permeability within the wood caused by the microwave drying makes the relaxation time of free water to rise up.

Effects of Microwave Vacuum Drying on Macroscopic Properties and Microstructure of Lotus (Nelumbo nucifera Gaertn.) Seeds

2018 ◽  
Vol 14 (3) ◽  
Author(s):  
Yingting Zhao ◽  
Yajun Jiang ◽  
Yimei Zheng ◽  
Zhiyu Li ◽  
Yaling Zhang ◽  
...  
Keyword(s):  
Fractal Dimension ◽  
Structural Characteristics ◽  
Nelumbo Nucifera ◽  
Microwave Drying ◽  
Vacuum Drying ◽  
Drying Methods ◽  
Microstructural Changes ◽  
Shrinkage Ratio ◽  
Microwave Vacuum Drying ◽  
Box Counting Method

AbstractThe structural characteristics of lotus (Nelumbo nuciferaGaertn.) seeds preserved by microwave vacuum drying (MVD) were investigated under various drying parameters, including microwave power density and vacuum degree. Dried lotus seeds were examined for microstructure by field emission scanning electron microscopy. Fractal dimension of the microscopic images was calculated by the box counting method. The apparent physical changes of the seeds, namely shrinkage ratio, rehydration rate, and hardness index, were determined to correlate well with their microstructural changes computed by the normalized changes of the fractal dimension (ΔFD/FD0). The samples at −90 kPa, 15 W/g exhibited a lower shrinkage ratio (46.2 %), higher rehydration rate (187.5 %) and lower hardness (3692.4 N). Although the physical and microstructural changes of the samples prepared by different drying methods (MVD, microwave drying, and hot air drying) varied, the changes of the ΔFD/FD0of the dried samples exhibited the same trends.

Growth and Development of the Florunner Peanut Cultivar as Influenced by Population, Planting Date and Water Availability1

1987 ◽  
Vol 14 (1) ◽  
pp. 11-16 ◽  
Author(s):  
C. S. Kvien ◽  
C. L. Bergmark
Keyword(s):  
Growth And Development ◽  
Dry Matter ◽  
Planting Date ◽  
Yield Response ◽  
Canopy Closure ◽  
Planting Dates ◽  
Late Planting ◽  
Arachis Hypogaea L ◽  
Competition For Light ◽  
Effect On Yield

Abstract The influence of planting date, plant population, and row pattern on peanut (Arachis hypogaea L.) growth and development was studied at two locations in Georgia. Twin rows were found to give faster canopy closure at high populations (212,000 plants ha-1) but not at low populations (26,500 plants ha-1). No yield differences due to row pattern were found. Increasing population increased competition for light which increased plant height and the percent of total dry matter partitioned to the stem. Population effect on yield was dependent on planting date and environmental conditions. When an optimum planting date (28 April 1983) was combined with adequate moisture (65 cm of water during season), increasing population from 30,000 to 240,000 plants ha-1 increased yield from 5290 to 6840 kg ha-1. A combination of an optimum planting date and moisture-limiting conditions (33 cm) resulted in a positive yield response of 20% as population was increased from 26,000 to 208,000 plants ha-1. Combining a late planting date (3 June 1983) with either adequate moisture (66 cm) or moisture-limiting conditions (35 cm) resulted in no yield response due to population. Late planting dates significantly reduced grade.

Sign in / Sign up

Export Citation Format

Share Document