• Journal of Biosystems Engineering
• /
• 제41권2호
• /
• pp.93-97
• /
• 2016

Purpose: Grain slurry diet are described as food obtained from ground grain paste. They serve as highly nutritious food for both adults and infants in Nigeria because of their immense nutritive and economical value. However, the production of these grain slurry diets is confronted with challenges that have hampered their commercialization. This study examines the trends and constraints of grain slurry food processing in Kaduna State. Methods: A survey was conducted using a structured questionnaire to elicit information from 192 selected processors, including both men and women. The survey was structured in line with the study objectives. The information was collated and synopsized into frequency distribution. Results: These findings revealed that 80% of the respondents processed between 1.0 tons and 13.0 tons of grain slurry per month. More than 90% of the processors processed grain slurry into koko, kunu, agidi, and pito. Accordingly, 80% of the interviewed processors indicated that sieving is one of the major constraints. Furthermore, inadequate modern machinery required to perform this operation makes it highly discouraging. One of the major challenges faced by the grain slurry producers in Nigeria is the lack of processing machinery for most operations (39.1%), followed by the tedious processing nature (27.1%), high labor cost (18.1%), and lack of market (9.4%). The traditional method of grain slurry processing was more popular than using modern equipment, except milling (96.5%), which is the only mechanized unit operation in grain slurry processing. Conclusion: Grain slurry processing and marketing were found to be profitable. However, these limitations could extremely reduce the level of grain slurry production, processing, and economic returns, thereby affecting the general wellbeing of the processors. The study also raised concerns about the safety and hygiene associated with traditionally processed grain slurry diets in the investigated areas.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2004년도 추계학술대회논문집
• /
• pp.99-102
• /
• 2004

In rheo forming process, slurry making is very important factor because the microstructure of slurry affects the quality of final products. To control the microstructure of slurry, slurry making by new rheo die casting was studied. In new rheocasting method, processes parameters are degree of overheat in molten metal, cooling condition, high frequency induction heating condition and cup temperature. Microstructures according to these parameters were observed. By image analysis, equivalent diameter and roundness of grain were investigated and discussed. To find out mechanical properties of grain controlled aluminum part by rheo die casting, tensile tests were carried out to the T6 heat treatment.

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제14권1호
• /
• pp.11-19
• /
• 2014

A colloidal silica slurry has been manufactured by mixing nano silica powders having different grain size to improve the reliability of Sapphire wafer CMP process. The main reliability problem of CMP process such as the breaking of wafer can be prevented by reducing the size of particles in a slurry. While existing commercial colloidal silica slurries are usually made of single grain size silica powder of about 120nm, in the present study 40nm and 100nm silica powders are mixed to achieve a similar removal rate. The new colloidal silica slurry showed wafer removal rate of $3.04{\mu}m/120min$ while that of a commercial colloidal silica slurry was $3.03{\mu}m/120min$. The roughness was less than $4{\AA}$ and scratch was 0. It is also expected that the reduction of the size of nano silica particles can improve the dispersion stability and prolong the useful life of the slurry.

• 산업기술연구
• /
• 제24권A호
• /
• pp.251-261
• /
• 2004

A series of column test with a silty marine soil mixed with Jumunjin Standard Sand were performed to investigate the characteristics of settling and consolidation of non-plastic dredged soils. Column tests were carried out by using the separable column to measure the grain size distribution of consolidated layer. Column tests were performed with changing the mixing ratio of Jumunjin Standard Sand to the silty marine soil, initial water content of slurry and initial height of slurry. Height of interface of slurry was monitored during tests and grain size distribution tests were carried out after finishing tests. Influencing factors on the particle segregation, eventually to the characteristics of settling and consolidation of non-plastic soil, were analyzed on the thesis of test results. As results of column tests, the mixing ratio of sand to the silty marine soil and the initial water content of slurry were known to affect the characteristics of settling and consolidation resulted in significant particle segregation of slurry. Initial height of slurry was found not to affect seriously to particle segregation.

• 한국축산시설환경학회지
• /
• 제10권2호
• /
• pp.75-80
• /
• 2004

본 연구는 액상분뇨 시용방법의 벼의 생육특성, 수량, 수량구성 요소, 쌀 품질에 미치는 영향을 구명하기 위하여 실시되었다. 처리는 액상분뇨를 기비만 처리한 처리구, 액상분뇨를 기비로 시용하고 화학비료를 추비로 시용한 시험구, 대조구로 화학비료 시용구를 두었다. 시험결과를 요약하면 아래와 같다. 1. 초장은 생육초기 화학비료구가 가장 큰 것으로 나타났으나 생육후기에는 초장의 차이가 처리구 간에 크지 않았다. 분얼 수의 경우도 화학비료구가 액비 시용구보다 더 많았다. 엽록소 함량은 생육초기 화학비료 시용구에서 생육 후기에는 처리간에 유의한 차이가 없었다. 2. 수량구성 요소에 있어서 주당수수는 화학비료구가 가장 많은 것으론 나타났다. 수당립수는 액상분뇨 시용구에서 가장 많았으며 천립중은 시비처리구 사이에 차이가 없는 것으로 나타났다. 등숙율에 있어서는 화학비료 시용구가 높은 것으로 나타났다 3. 벼의 정조수량은 화학비료 시용구에서 가장 높았고 액비+화학비료구에서 $3\%$ 액상분뇨 시용구에서 화학비료 시용구 대비 $5\%$ 감수되었다. 4. 쌀 품질은 액상분뇨 시용구와 액비기비 +화학비료 추비구가 화학비료구에 비해 상당히 높게 나타났다. 단백질 함량은 액비 시용구가 화학비료 시용구보다 유의성있게 낮았다. 따라서 쌀 품질 향상에 적절한 양의 액비 시용이 효과가 있는 것으로 나타났다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2004년도 추계학술대회 논문집
• /
• pp.668-671
• /
• 2004

The mechanics of the dendrite fragmentation is a very important aspect of grain refinement in rheocasting. In this work, the stress field of the dendrite stirred in the semisolid slurry was simulated by Metlab 6.0 software. The result shows that stress concentration at the root of the dendrite arms is great enough to cause plastic deformation though the agitation is moderate. Accordingly, dendrite fragmentation was suggested to be caused by fractured after fatigue erosion.

• 한국세라믹학회지
• /
• 제47권6호
• /
• pp.485-490
• /
• 2010

In our previous studies, continuous SiC fiber-reinforced SiC-matrix composites ($SiC_f$/SiC) had been fabricated by two different slurry infiltration methods: vacuum infiltration and electrophoretic deposition (EPD). 12 wt% of $Al_2O_3-Y_2O_3$-MgO with respect to SiC powder was used as additives for liquid-phase assisted sintering. After hot pressing at $1750^{\circ}C$ under 20 MPa for 2 h in Ar atmosphere, a high composite density could be achieved for both cases, whereas the problems such as large grain size and non-uniform distribution of liquid phase were observed, which was resulted in the relatively poor mechanical properties of composites. Therefore, efforts have been made to reduce the grain growth during the sintering, including the optimization for hot pressing condition and utilization of spark plasma sintering using a SiC monolith. Based on the results, spark plasma sintering was found to be effective method in decreasing the amount of sintering additive, time and grain growth, which will be explained in comparison to the results of hot pressing in this paper.

• 한국세라믹학회지
• /
• 제51권5호
• /
• pp.466-471
• /
• 2014

Hydrous zirconia particles were prepared from $ZrOCl_2$ aqueous solution using an electro-dialysis [ED] process. For the preparation of $(Zr,Y)(OH)_4$ precipitates, 3 mol% $YCl_3$ was added into $ZrOCl_2$ aqueous solution. During the hydrolysis of 0.5 mol/L $(Zr,Y)OCl_2$ solution at $90^{\circ}C$ a slurry solution was obtained. The ED process was used for the removal of chlorine from the slurry solution. Two kinds of slurry solution were sampled at the beginning and end of the ED process. The morphology of hydrous zirconia particles in the solution was observed using an inverted optical microscope and an FE-SEM. The hydrous zirconia particles were nano-crystalline, and easily coagulated with drying. Yttrium stabilized zirconia [YSZ] powder could be obtained by the calcination of $(Zr,Y)(OH)_4$ precipitates prepared from a $(Zr,Y)OCl_2$ solution by the ED process. The coagulated dry powders were shaped and sintered at $1500^{\circ}C$ for 2 h. The sintered body showed a dense microstructure with uniform grain morphology.

• 한국정밀공학회지
• /
• 제16권6호
• /
• pp.36-44
• /
• 1999

The rapid Tooling technique is classified into two methods: one to directly utilize the model which was made by rapid prototyping technologies for dies, and the other to make a transferred type using the model as a master model and create dies and molds using it. In this study, the Al powder filled resin was made several mixed ratios and meshes sizes, and applied to slurry casting. And, variation of mechanical characteristics such as the shrinkage rate, the tensile strength, the elongation, the hardness, and surface roughness, are measured to compare. Consequently, as higher is the powder mixed ration and as smaller is the grain size of the power, the mechanical characteristics of the final mold are improved. Finally, the metal short fiber which can be fabricated easily and cheaply, if the self-excited vibration of an elastic tool, was also applied to slurry casting. It has been found tat the hardness gets higher, while the shrinkage rate lower, if mixed with short fiber.

• 한국세라믹학회지
• /
• 제55권4호
• /
• pp.337-343
• /
• 2018

The influence of solid loading in the slurry composition on the morphology of 3Y-TZP granules fabricated by two-fluid spray drying was investigated for solid contents varying between 30 wt% and 50 wt%. The resulting 3Y-TZP granules showed a sphere-like shape with diameters of $40-70{\mu}m$. However, a donut-like shape and a few cracks were observed on the granule surfaces fabricated using the slurry with 50 wt% solid content. The green density after cold isostatic pressing at 200 MPa was $2.1-2.2g/cm^3$, and a homogeneous fracture surface was obtained by complete destruction of granules. After sintering at $1500^{\circ}C$ for 2 h, all specimens had relative densities of 96.2 - 98.3%. With increasing solid content, the relative density decreased from 98.3% to 96.2%, but the grain size increased from $0.3{\mu}m$ to $0.6{\mu}m$. Highly sinterable zirconia granule powder could be obtained by controlling the slurry composition.