• Journal of the Korean Wood Science and Technology
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• 제37권5호
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• pp.421-425
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• 2009

This research investigates the effect of copper retention on copper leaching in wood treated with copper-based preservatives. Radiata pine (Pinus radiata D. Don) sapwood samples were ground in a Wiley mill equipped with a 20-mesh screen. The ground wood was vacuum-treated with various concentrations of alkaline copper quat (ACQ), bis-(N-cyclohexyl-diazeniumdioxy)-copper (CB-HDO), and copper azole (CUAZ). The treated samples were conditioned at $70^{\circ}C$ and 100% RH for 72 hours. The samples were leached by using the distilled water for four weeks, and the copper contents in each sample were measured by X-ray spectroscopy. As expected, the copper leaching was increased with increasing of copper retention. The copper leaching from the ACQ and CB-HDO treated samples were gradually decreased with increasing copper retention: however, the copper losses from the CUAZ treated samples appeared to be proportionally increased with the increase in copper retention in all retention levels tested. The results indicate that at the conditions of the same copper retention ACQ and CB-HDO treated wood have a better leaching resistance compared to CUAZ treated wood.

• Journal of the Korean Wood Science and Technology
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• 제26권3호
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• pp.48-52
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• 1998

Residues such as walnut, pinenut and peanut shells were used as a filler in adhesive for bonding radiata pine plywood. The nutshell residues were prepared by simply drying to 8% moisture content and grinding the dry material using a laboratory Wiley mill with a $75{\mu}m$ (200 mesh) screen. The nutshells residues were compared to a commercial filler commonly used in adhesives by the structural plywood and laminated veneer lumber industry in the United States. The adhesive mixes were made by following the recommended procedure of Georgia-Pacific Resins, Inc., using phenol-formaldehyde resin. For each filler type, three-ply plywoods, 6 mm nominal thickness and 30 by 30 cm in size, were fabricated at two press times (4 and 5 min) and around 30 minute assembly time. Evaluations of the nutshell residues were carried out by tension shear tests after cyclic boil tests on plywood. The results of the performance test included tension shear strength and wood failure. All plywoods made with the nutshell fillers were comparable to those made with the control filler. These results indicate that nutshell residues would be suitable as filler for plywood adhesives.

• 한국재료학회지
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• 제24권8호
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• pp.413-416
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• 2014

The effects of an addition of CNT on the sensing properties of nano ZnO:CNT-based gas sensors were studied for $H_2S$ gas. The nano ZnO sensing materials were grown by a hydrothermal reaction method. The nano ZnO:CNT was prepared by ball-milling method. The weight range of the CNT addition on the ZnO surface was from 0 to 10%. The nano ZnO:CNT gas sensors were fabricated by a screen-printing method on alumina substrates. The structural and morphological properties of the ZnO:CNT sensing materials were investigated by XRD, EDS, and SEM. The XRD patterns revealed that nano ZnO:CNT powders with a wurtzite structure were grown with (1 0 0), (0 0 2), and (1 0 1) dominant peaks. The size of the ZnO was about 210 nm, as confirmed by SEM images. The sensitivity of the nano ZnO:CNT-based sensors was measured for 5 ppm of $H_2S$ gas at room temperature by comparing the resistance in air with that in target gases.

• 농업과학연구
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• 제12권1호
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• pp.101-107
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• 1985

사료(飼料)의 해외의존도(海外依存度)가 높은 우리나라의 축산경영농가(畜産經營農家)의 안정적(安定的) 발전방향(發展方向)은 사료(飼料)의 자급율(自給率)을 높이는 것이 매우 중요(重要)한 긴급과제(緊急課題)이다. 따라서 본(本) 연구(硏究)는 축산농가(畜産農家)에서 손쉽게 구(求)할 수 있는 보리와 건초(乾草)를 사용(使用)하여 사료(飼料)의 공급율(供給率)을 증가(增加)시키기 위(爲)한 대책(對策)의 하나로 현재(現在) 우리나라 농촌(農村)에 널리 보급(普及)되어 있는 3.7~7.5 kW 동력경운기(動力耕耘機)로 구동(驅動)이 가능(可能)한 소형사료분쇄기용(小形飼料粉碎機用) 햄머의 설계자료(設計資料)를 제공(提供)하고자 사료분쇄기(飼料粉碎機)의 적정회전수(適定回轉數)인 3,000rpm을 유지(維持)하면서 햄머의 폭(幅)은 20mm, 30mm, 40mm로, 두께를 2mm, 4mm, 6mm로 변화(變化)시키면서 성능실험(性能實驗)을 실시(實施)하였다. 공시재료(供試材料)는 보리와 건초(乾草)를 사용(使用)하고, 스크린은 구멍크기가 보리 4.76mm, 건초(乾草) 3.18mm인 것을 사용(使用)하여 분쇄성능실험(粉碎性能實驗)을 실시(實施)하여 분석(分析)한 결과(結果)는 다음과 같다. 1. 시료(試料)를 분쇄(粉碎)한 결과(結果), 입자(粒子)크기는 보리 478~774 micron, 건초(乾草) 350~434 micron으로 햄머의 두께와 폭(幅)이 증가(增加)함에 따라 감소(減少)하였다. 2. 분쇄물(粉碎物)의 조도계수(組度係數)는 보리 3.07~3.62. 건초(乾草) 2.69~2.93으로 햄머의 두께와 폭(幅)에 반비례(反比例)하였다. 3. 시료(試料) 분쇄시(粉碎時) 소요동력(所要動力)은 보리 3.8~5.0 kW, 건초(乾草) 0.9~1.4 kW로 햄머의 폭(幅)보다는 두께가 더 크게 영향(影響)을 미치는 것으로 분석(分析)되었다. 4. 소형사료분쇄기(小形飼料粉碎機)의 분쇄성능(粉碎性能)은 보리 99~170 kg/kW.h, 건초(乾草) 11~21 kg/kW.h이며, 햄머의 두께가 큰 영향(影響)을 마치는 인자(因子)로서 두께가 증가(增加)할 수록 분쇄성능(粉碎性能)은 감소(減少)하나 조도계수(粗度係數) 3.2 범위(範圍)에서는 두께 4mm가 가장 양호(良好)하였다. 햄머의 폭(幅)은 소형사료분쇄기용(小形飼料粉碎機用)으로는 30mm가 적정치(適正値)인 것으로 나타났다.

• 농약과학회지
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• 제8권3호
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• pp.220-230
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• 2004

본 연구의 목적은 내의 자생식물 중 살포활성이 있는 식물 종을 선발하는데 있다. 국내의 자생식물 55과 98종 시료로터 MeOH 조추출물을 얻은 다음 24-well plate에서 유채(Brassica napus L.)에 대한 살초검성을 수행하였다. 본 연구에 사용된 98종 중 놀은 살포활성($GR_{50}$ 값 < 1,000 ${\mu}g\;g^{-1}$)을 나타낸 식물은 가중나무(Ailanthus altissima (MILL.) SWINGLE), 고비(Osmunda japonica THUNB.), 더위지기(Artemisia iwayomogi KITAMURA), 두릅(Aralia elata SEEM.), 떡쑥(Gnaphalium affine D. DON), 미국산사나무(Crataegus scabrida SARG.), 사군자(Quisqualis indica L.), 센달나무(Machilus japonica S. et Z.), 소귀나무(Myrica rubra S. et Z.), 실육카(Yucca smalliana FERN.), 양버즘나무(Platanus occidentalis L.), 영춘화(Jasminum nudiflorum LINDL.), 유채(Brassica campestris subsp. napus var. nippo-oleifera MAKINO), 음나무(Kalopanax pictus (THUNB.) NAKAI), 자리공(Phytolacca esculenta V. Houtte), 장딸기(Rubus hirsutus THUNB.), 젓나무(Abies holophylla MAXIM.), 족도리풀(Asarum sieboldii MIQ.), 참으아리(Clematis terniflora DC.), 캐모마일(Anthemis nobilis L.) 등 20종으로 나타났다. 자생식물 98종 중 50종 식물은 중정도의 살초활성을 나타내었으나(1,000 ${\mu}g\;g^{-1}$ < $GR_{50}$ 값 < 2,000 ${\mu}g\;g^{-1}$), 28종 식물은 살초활성을 전혀 나타내지 않았다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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• pp.99-103
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• 2006

Use of recycled fibers in papermaking has been increased for economical and environmental reasons. Recycled panels are major liber resources for brown grades and newsprints. Since the recycled fibers have disadvantageous properties as raw materials for papermaking it is of great importance to optimize the use of these recycled fibers. OCC (Old Corrugated Containers) is the major fiber source for linerboards and corrugating mediums that require diverse specification in strength properties. Many studies have been focused to overcome the problems of strength reduction of brown grades when recycled fibers are used as raw materials. The problem of strength loss for papers made from recycled fibers is closely associated with the increased amount of fines in recycled fibers and hornification of fibers. Fines contained in the recycled fiber resources cause problems not only in paper properties but also in process runnability. This shows that the optimal management and proper use of fines in recycling papermaking system are critical to get most benefits of using recycled fibers. In this study some approaches for optimal use of fiber fines in recycled paper mill have been investigated. Stock samples, prepared in the laboratory and obtained from a recycling plant were used. Fractionation of these samples was made using Sweco screen. And the effect of the addition of polyelectrolytes including cationic PAM and PEI on drainage and retention was evaluated. Different methods of polymer addition were compared to find the most effective ways of treating recycled fiber stocks with polyelectrolytes. Addition of polyelectrolytes to the short fiber fraction was most effective in retention and drainage. The influence of the charge and molecular weight of these two polymers has been examined and discussed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1246-1247
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• 2008

With recent advanced in portable electric devices, wireless sensor, MEMS and bio-Mechanics device, the new typed power supply, not conventional battery but self-powered energy source is needed. Particularly, the system that harvests from their environments are interests for use in self powered devices. For very low powered devices, environmental energy may be enough to use power source. Therefore, in other to made piezoelectric energy harvesting device, PMN-PZT thick film was formed by the screen printing method on the Ag/Pd coated alumina substrate. The layer was 8 layers and slurry where a-terpineol, ethycellulose, ferro B-75001 as Vehicle, PMN-PZT powder used are fabricated by ball mill. The output power quality was be also investigated by changing the load resistance, weight and frequency. The made piezoelectric energy harvesting device was resulted from the conditions of 33$k{\Omega}$, 0.25g, 197Hz respectively. The thick film was prepared at the condition of 2.75Vrms, and its power was 230${\mu} W$ and its thickness was 56${mu}m$. The piezoelectric energy harvesting device output voltage was increased, when the load weight, load resistance was increasing and resonance frequency was diminishing. The other side, resonance frequency was diminished, when the weight was increasing. And output power was continuously it changed by load resistance, output voltage, weight and resonance frequency.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.224-230
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• 2001

This study was conducted to evaluate the extruding effects of corn and wheat on growth performance and fecal digestibility of amino acids in early-weaned pigs. Ground corn and wheat by a hammer mill (3 mm screen in diameter) were extruded at $130{\pm}2^{\circ}C$ with a moist-type extruder ($Matador^{(R)}$). Treatments were: 1) 3 mm ground corn, 2) extruded corn, 3) 3 mm ground wheat, and 4) extruded wheat. A total of 160 pigs (14 d of age and $4.3{\pm}0.74kg$ BW) were allotted with the dietary treatments for a 21-d feeding trial. All diets were mash and contained 30% corn or wheat products. For a digestibility trial, 16 pigs (14-d old and $4.2{\pm}0.32kg$ BW) were employed in individual metabolic crates. There were no differences (p>0.15) in growth performance between corn-fed and wheat-fed groups. Feeding pigs diets containing extruded corn or wheat did not affect ADG (p>0.15) and ADFI (p>0.15), but it improved feed/gain (p<0.01). Also, feeding pigs diets containing extruded corn or wheat had lower true fecal digestibilities of arginine, histidine, isoleucine, lysine and valine (p<.007) in the pigs. In conclusion, our results suggest that extruding corn and wheat had no benefit on the growth of early-weaned pigs.

• Asian-Australasian Journal of Animal Sciences
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• 제10권2호
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• pp.170-177
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• 1997

Two experiments were conducted to evaluate the effects of different extrusion conditions of corn and soybean meal on physico-chemical properties, ileal digestibility of amino acid and growth performance in weaned pigs. In Expt. 1, to compare physico-chemical properties and ileal digestibility of extruded corn and soybean meal, ground corn (2 mm screen) and soybean meal were separately extruded in four different conditions: (1) no preconditioning, low water supply (3.0 l/min) (NCLW), (2) no preconditioning, high water supply (7.0 l/min) (NCHW). (3) preconditioning (steam 3.0 l/min) with low water supply (3.0 l/min) (CLW), and (4) preconditioning (steam 3.0 l/min) plus high water supply (7.0 l/min) (CHW). Twenty-five cannulated pigs ($L{\times}Y{\times}D$, 7.62 kg BW for soybean meal, 8.80 kg BW for corn) were employed to determine nutrients digestibility of the extruded feedstuffs. In Expt. 2, a total of 90 pogs ($L{\times}Y{\times}D$, 9.18 kg BW) were used for a 28 d feeding trial to compare growth performance of pigs as affected by different extrusion conditions. Before mixing, corn and soybean meal were blended and extruded by the same conditions as described in Expt. 1. corn extruded with NCLW showed the highest (p < 0.05) degree of gelatinization (DG), compared to the lowest values observed for NCHW. Extrusion of corn with preconditioning (CLW and CHW) increased (p < 0.05) the DG as compared to the extrusion condition of NCHW. Extruded SBM with NCLW showed the lowest (p < 0.05) degree of texturization among treatments. The ileal digestibility of GE in SBM was higher with NCHW and CHW as compared to NCLW. The ileal digestibility of CP was lower in extruded corn, but was higher in extruded SBM, compared to untreated sample. Lysine digestibility of extruded corn (except corn with NCHW) was in general significantly improved. Extrusion of SBM resulted in no improvements in ileal digestibility of amino acids, but extruded SBM with NCLW had lower lysine digestibility compared to other treatments. In growth responses, pigs fed a diet with CLW had higher, but not significant, average daily gain (ADG) than other treatments during first 2 weeks. From d 15 to 28, pigs fed a diet with CHW had significantly less (p < 0.05) average daily feed intake (ADFI) than others except NCHW. In conclusion, the proper extrusion condition for corn and SBM in terms of ileal digestibility of amino acids and growth performance of weaning pigs seems to be the combination of preconditioning and a low water supply (3.0 l/min).

• 한국유기농업학회지
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• 제26권2호
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• pp.281-296
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• 2018

본 연구에서는 재고미의 사료가치 평가를 위해 무처리(Control)를 비롯한 Extruding, Roasting, Steam 처리구들의 영양소 성분분석, in vitro 소화율, in situ 소화율을 분석하였다. In vitro 실험에서 Extruding은 건물 소화율과 gas 발생량이 타 처리구에 비해 상대적으로 높았고, 가장 낮은 pH를 보였으며, 특히 배양 시간 초기에 소화가 신속히 발생하였다. $NH_3-N$ 함량은 배양 6 h 이후에서 Control이 Extruding, Roasting, Steam에 비해 유의적으로 높은 값을 보였고, 이는 가열처리된 단백질의 반추위 미생물의 이용성 저하에 따른 결과로 보이나, 더 정확한 결과를 위해 건물 소화율 분석뿐 아니라 CP 소화율 분석이 필요할 것으로 사료된다. VFA 발생량에서는 Extruding이 다른 처리구들에 비해 배양 6, 12 h에서 유의적으로 높았는데 이는 Extruding 처리구의 분해가 배양 초기에 주로 이어져 발생한 결과로 추정된다. 전분을 발효시키는 박테리아에 의해 높은 비율로 생산되는 propionate 증가 폭에서도 같은 경향을 보였다. In situ 소화율은 in vitro의 소화율과는 다소 차이가 있는 것으로 여겨지나, 이는 실험 방법에 대한 오차로 여겨질 수 있으며, ED(유효분해율)를 통해 in vitro 시험과 소화율의 경향성이 유사한 것을 알 수 있었다. 따라서 본 연구결과를 근거로 상대적으로 적합한 사료가공 처리방법은 무처리, Roasting 및 Steaming인 것으로 보여진다. 또한 무처리(control)의 경우 가공처리에 따른 추가비용 발생이 없으므로 경제적으로 유리할 것으로 판단된다. 재고미가 TMR의 원료로 이용될 수 있다면 국내에서 자급 가능한 사료원료로써 우수한 경제성을 지닐 수 있을 것이다.