• 한국수산과학회지
• /
• 제49권6호
• /
• pp.766-771
• /
• 2016

The pacific oyster Crassostrea gigas has a desirable taste and flavor that differs from those of other fish and shellfish. In order to develop a high value-added product from individually quick-frozen oyster extract (IQFOE), we prepared an oyster granular flavor seasoning (OGS) from IQFOE and characterized its qualities. The OGS was prepared by granular molding and fluidized bed drying with inosine monophosphate (IMP, 0.1%), yeast extract powder (1.4%), tangle extract powder (0.6%), monosodium glutamate (MSG, 5.0%), microcrystalline cellulose (0.6%), lactose (27.5%), salt (33.0%), spray-dried IQFOE (22.5%) as a powdered materials, and IQFOE ($Brix\;25^{\circ}$, 7.0%), soy sauce (0.4%) and water (1.7%) as a liquid materials. The moisture, crude protein, pH and salinity of the OGS were 3.4%, 12.5%, 6.50 and 32.0%, respectively. Especially, the OGS revealed very higher amino-N content (1,856.0 mg/100 g) than that (1,291.2-1,610.2 mg/100 g) of other commercial flavor seasonings. In taste-active compounds, free amino acid contents was 1,359.0 mg/100 g, and major ones were glutamic acid, taurine, hydroxyproline, glycine, lysine, phosphoserine, proline in order. And OGS showed good organoleptic qualities for taste, odor and general preference compared with commercial flavor seasonings on a local market.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
• /
• pp.181-182
• /
• 2006

Cylindrical specimens with different levels of density have been submitted to uniaxial compression tests with loading and unloading cycles. The analysis of the elastic loadings shows a non linear elasticity which can be mathematically represented by means of a potential law. Results are explained by assuming that the total elastic strain is the contribution of two terms one deriving from the hertzian deformation of the contacts among particles and another that takes into account the linear elastic deformation of the powder skeleton. A simple model based in an one pore unit cell is presented to support the mathematical model.

• Korea-Australia Rheology Journal
• /
• 제12권1호
• /
• pp.55-67
• /
• 2000

In this paper, an experimental study of the rheological behavior of granular flow in a new type of storage silo is presented. The main characteristic of the new design is a hexagonal shape chosen with the objective of minimizing the stresses applied to the stored grains, and to reduce grain damage during the filling and emptying processes. Measurements of stress distribution and flow patterns are shown for a variety of granular materials. Because of the design of the silo, the granular material adopts its natural rest angle at all times eliminating collisional stresses and impacts between grains. A homogeneous, low friction flow is naturally achieved which provides a controlled stress distribution throughout the silo during filling and emptying. Secondary dynamic stresses, which are responsible for wall failure in conventional silos of the vertical type, are completely eliminated. A comparison between the two geometries is presented with data obtained for these silos and a number of granular materials. The discharge pattern inhibits powder formation in the silo and the filling system virtually eliminates unwanted material packing. Finally, notwithstanding the rheological advantages of this new design, the hexagonal cells that constitute the silo have many other advantages, such as the possible use of solar energy to control the humidity inside them. The cell type design allows for versatile storage capabilities and the elevation above the ground provides unlimited transportation facilities during emptying.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
• /
• pp.177-178
• /
• 2006

The results of monotonic and cyclic uniaxial compression tests, in which the deviatoric component of the stress is predominant, carried out on green and recrystallized iron compacts with different levels of density are presented and discussed in order to analyse the macro and micro-mechanisms governing the mechanical behaviour of non-sintered PM materials. The plastic deformation of the particles, especially at the contact areas between neighbouring grains, produces an internal friction responsible for the main features observed in the behaviour of green metallic compacts. These results show important discrepancies with the plasticity models, Cam-Clay and Drucker-Prager Cap.

• 한국세라믹학회지
• /
• 제14권3호
• /
• pp.163-168
• /
• 1977

As a wet chemical drying process "hot petroleum drying method" was applied and developed for preparing uniformly fine oxide powder with high purity and sinterreactivity. Using this method solution of sulfates was dried in hot petroleum bath (~17$0^{\circ}C$) to sulfate powder from which corresponding mullite doped by Fe3+ ion was formed. Particle size, shape, decomposition by heat, and phase identification of sulfate andoxide powders determined by DTA, TGA, X-ray diffraction, analysis and electron microscopy: sulfate powder prepared by this drying method is an intimate mixture of the amorphous form of uniformly and finely distributed spherical particles (0.05-0.1$\mu$). Mullitization with the sulfate powder occurs at 110$0^{\circ}C$ in air. The morphology of mullite particle made by firing the sulfate powder at 135$0^{\circ}C$ in oxygen atmosphere is granular of 0.1-0.3$\mu$ in size. This drying process proved to be a very effective method for preparing fine, homogeneous, and highly sinterreactive multicomponent oxide powder without conventional ceramic process of mixing, milling, and granulating. This process can be also applied for preparing electronic ceramic materials which are requisite for high purity and homogeneity.mogeneity.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
• /
• pp.264-265
• /
• 2006

The directions of further developments in the modeling of sintering are pointed out, including multi-scale modeling of sintering, on-line sintering damage criteria, particle agglomeration, sintering with phase transformations. A true multi-scale approach is applied for the development of a new meso-macro methodology for modeling of sintering. The developed macroscopic level computational framework envelopes the mesoscopic simulators. No closed forms of constitutive relationships are assumed for the parameters of the material. The model framework is able to predict the final dimensions of the sintered specimen on a global scale and identify the granular structure in any localized area for prediction of the material properties.

• 한국잠사곤충학회지
• /
• 제43권1호
• /
• pp.33-36
• /
• 2001

This study was carried out to improve the liquid culture methods of Paecilomyces japonica. The results show that the size of granular mycelium is smaller when the shaking speed is increased. Especially, the granular mycelium is the smallest at the shaking speed of 150rpm under the photoperiod of 12L-12D. Dry weight of mycelium was averagely 1.216 g in the Sikworm larva (SL) medium, and the weight was 2 times heavier than in the Potato dextrose (PD) medium. By adding 6 g of 6 mmbeads in the SL medium, the dry weight is increased to 1.332 g. The optimal addition of silkworm larval powder to the culture medium for gest harvest was 1.360$\pm$0.67 g in dry weight.

• 농약과학회지
• /
• 제9권3호
• /
• pp.262-267
• /
• 2005

유기합성농약의 부작용을 최소화하고, 미생물 농약의 실용화를 목적으로 Paenibacillus sp. AC-1 건조 분말 그리고 여러 가지 보조제 및 증량제를 이용하여 입제를 제조하였으며, 이들 제제에 대한 물리화학적 특성을 연구하였다. 시제품은 Paenibacillus sp. AC-1 건조분말을 사용하여 고추역병 방제용 입제 4종을 제조하였다. 증량제 종류별 원제에 대한 영향은 talc가 가장 안정하였으며, 시제품 제조시 균주 생존성은 시제품 모두 제조 후에 안정하였다. Paenibacillus sp. AC-1 건조분말을 사용한 시제품의 물리화학적 특성 중 시제품 모두 입제의 품질규격에 적합하였다. Paenibacillus sp. AC-1 건조분말을 사용한 입제의 저장온도별 균주 안정성은 $4{\sim}50^{\circ}C$의 온도 범위에서 12주후까지도 안정하였다. 입제의 균 수중용출은 처리 7시간 후에 Paenibacillus sp. AC-1 균이 90% 이상 용출되었으며, 입자붕괴성은 처리 1일 후에 완전히 붕괴되었다. 이상의 결과를 종합할 때, Paenibacillus sp. AC-1를 이용한 고추역병 방제용 미생물 살균제의 실용화를 위한 제조처방은 원제로서 AC-1 건조분말 20%, 보조제로서 sodium polyacrylate 1.0%, 계면활성제로서 polycarboxylate를 주제로한 제제 7%, 증량제로서 나머지를 talc로 사용하는 것이 Paenibacillus sp. AC-1의 입제 제조에 최적 조건이었다.

• 한국분말재료학회지
• /
• 제24권2호
• /
• pp.102-107
• /
• 2017

Porous polytetrafluoroethylene (PTFE) thin films are fabricated by spin-coating using a dispersion solution containing PTFE powders, and their crystalline properties are investigated after thermal annealing at various temperatures ranging from 300 to $500^{\circ}C$. Before thermal annealing, the film is densely packed and consists of many granular particles 200-300 nm in diameter. However, after thermal annealing, the film contains many voids and fibrous grains on the surface. In addition, the film thickness decreases after thermal annealing owing to evaporation of the surfactant, binder, and solvent composing the PTFE dispersion solution. The film thickness is systematically controlled from 2 to $6.5{\mu}m$ by decreasing the spin speed from 1,500 to 500 rpm. A triboelectric nanogenerator is fabricated by spin-coating PTFE thin films onto polished Cu foils, where they act as an active layer to convert mechanical energy to electrical energy. A triboelectric nanogenerator consisting of a PTFE layer and Al metal foil pair shows typical output characteristics, exhibiting positive and negative peaks during applied strain and relief cycles due to charging and discharging of electrical charge carriers. Further, the voltage and current outputs increase with increasing strain cycle owing to accumulation of electrical charge carriers during charge-discharge.

• 한국세라믹학회지
• /
• 제31권12호
• /
• pp.1513-1520
• /
• 1994

Mechanical properties of hot-pressed SiC whisker/Al2O3 composites were strongly dependent on the granular characteristics of mixed powder, which were controlled by co-dispersion condition, the existence of steric barrier on whisker surface, and granulating method, etc. Heat-treatment of SiC whiskers at $700^{\circ}C$ for 1 hr in air was very effective both for achieving dispersion stability of whiskers with PVA adsorption and for obtaining excellent mechanical properties of resulting composites. It is believed from the fractography of composites prepared with various whisker dispersion conditions that the most common fracture origin of Al2O3 agglomerate could be attributed to whisker clusters arising due to flocculation. Further improvement of mechanical properties of composites were achieved by hot pressing green tapes prepared by Doctor-blade process, which promoted two-dimensional random alignment of whiskers.