This study demonstrated a rapid and simple method for the determination of seven anions including halides and oxyhalides from the KURT underground water sample by capillary electrophoresis with UV detection. In nuclear waste disposal, some anions such as iodine, selenium, and technetium have been of great concern due to its high mobility and toxicity with a long half-life. It has been needed for a reliable analysis of anionic speciation because the high mobility of anions is easily affected by environmental conditions especially pH and salinity of underground water. Here this project is to develop a fast separation of seven anions including iodide, iodate, and selenite using capillary electrophoresis. The electroosmotic flow (EOF) was suppressed using a poly (ethyleneglycol) -coated capillary (DB-WAX capillary). As a result, anions migrated depending on their mobility under a reverse polarity condition (-15 kV) and the analysis time was within 15 min. UV detection was used at 200 nm. The RSDs for migration time were between 0.7% and 1.3% except for selenite of 5.1%. The RSDs for peak area were obtained between 2.9% and 7.4%. The calibration curves were linear from 10 to 200 mg/L with correlation coefficients greater than 0.9952. The LODs were 7.3, 10.9, 11.3, 12.9, 13.0, 13.9, and 17.4 mg/L for iodide, nitrate, bromide, selenite, bromate, tungstate and iodate. The KURT underground water sample spiked with seven anions at 50 mg/L were analyzed. The recoveries of spiked KURT sample ranged from 93.4% to 99.3%. The proposed method was successfully applied to determine seven anions in underground water sample.

The incorporation of vertically aligned carbon nanotubes (VACNTs) between composites plies has been said to enhance the through-thickness strength, and it can also decrease the risk of interply delamination and reduce crack initiation. Thanks to these high mechanical performances, nano-engineered hybrid composites are seen as promising for highly demanding structural reinforcement applications. This paper is part of a study that focuses specifically on the methodology for transferring VACNTs onto a prepreg surface while maintaining their initial vertically aligned morphology. The chosen method involved bonding the VACNTs’ forest through capillary impregnation of the forest by the prepreg’s resin. Key parameters for an effective transfer and to achieve a partial capillary rise of the resin into the VACNTs will be discussed here.

The demand for energy is steadily rising because of rapid population growth and improvements in living standards. Consequently, extensive research is being conducted worldwide to enhance the energy supply. Transpiration power generation technology utilizes the vast availability of water, which encompasses more than 70% of the Earth's surface, offering the unique advantage of minimal temporal and spatial constraints over other forms of power generation. Various principles are involved in water-based energy harvesting. In this study, we focused on explaining the generation of energy through the streaming potential within the generator component. The generator was fabricated using sugar cubes, PDMS, carbon black, CTAB, and DI water. In addition, a straightforward and rapid manufacturing method for the generator was proposed. The PDMS generator developed in this study exhibits high performance with a voltage of 29.6 mV and a current of 8.29 μA and can generate power for over 40h. This study contributes to the future development of generators that can achieve high performance and long-term power generation.

본 연구는 임해 매립지에 조성되는 골프장 부지의 자연적 장해요인을 분석하고 개선 요소를 검토하 여 향후 매립지에 조성되는 식재공사 등의 시행착오를 줄이고 경제성을 향상시키고자 한다. 선행 연 구자들의 임해 매립지 토양 환경의 이화학적 연구 결과를 토대로 영종도 국제공항 내 골프장의 토양 환경을 개선하는 방법을 배수 처리 체계와 함께 연구하였다. 그 결과로 사업 초기 단계에서부터 수목 또는 식물의 생장을 고려한 계획을 통해 경제적이며, 장기적으로 정상적인 식물 또는 수목의 생장에 도움을 꾀하고자 하였다. 연구결과로서 임해 매립지에서 식물 생육에 영향을 주는 요인 중 염분 상승 또는 식생 지반의 염분 과다는 식물 생육에 직접적인 영향이 있는 것으로 분석되었고 따라서 임해 매립지의 경우 탈염 과정을 거쳐 식물 생육에 적합한 토양으로 개선하여야 될 필요가 있으며, 이 과정 에서 염분 상승의 차단을 위한 차단층의 설치가 필요하다. 특히 모세관 상승의 차단은 입도가 큰 재료 일수록 차단 효과가 컸으며, 실험 결과를 미루어 볼 때 차단층의 두께가 클수록 확실한 모세관 상승 차단 효과가 있을 것이라 판단된다. 본 연구는 임해 매립지 조성 시 염분 상승에 의한 식물 생육 저해 요소를 감소시키기 위한 방법으로 식재기반 조성 시 매립 방법을 달리하여 지하수위를 저하 시킴으로써 모세관 상승에 의한 염분 상승을 근본적으로 차단하고자 실험적인 방법을 통해 차단층의 재료 선정 및 차단층의 두께를 결정하는데 연구의 의의를 두고 있다. 그러나 식재 단면층의 조성 두께 등 의 설정은 실내시험으로 인한 한계를 보이고 있다. 특히 서남해안의 경우 환경적 영향(밀물과 썰물의 조위 차, 일조량, 풍향, 풍량 등 염분 상승)이 되는 인자들의 변수 조건에 대한 미적용의 한계성과 염분 차단층 설치 시 염분 상승은 기대할 수 있으나 모관수 차단으로 인한 건조피해에 대한 대책은 연구과 정에서 부족했던 부분이다 추후 부족한 부분에 대한 연구는 향후 지속적으로 계속되어야 할 것이다.

This paper considers the influence of internal heat exchanger and capillary tube on the efficiency of small refrigeration system using eco-friendly refrigerants such as R290, R600a, R1270, and R717. A refrigeration system using such internal heat exchanger and capillary tube may improve performance, but may degrade performance. Therefore, this paper used a mathematical model in a normal state to understand performance characteristics as to what change occurs when internal heat exchanger and capillary tube are attached to eco-friendly refrigerant based on R134a. In addition, the effects of operating conditions such as refrigerant flow rate, evaporation temperature, condensation temperature, subcooling degree internal heat exchanger length and capillary tube length were analyzed. The result showed that the evaporation temperature, condensation temperature, subcooling degree, internal heat exchanger length and capillary tube length had an effect on the refrigeration capacity and compression power. Therefore, it is necessary to design a refrigeration cycle using an eco-friendly refrigerant by grasping these effects in detail.

본 연구에서는 다공성 중공사형 분리막(multi-bore capillary membrane module)을 생물막 반응기(MBR)에 침지시켜 운전시간에 따른 흡입 압력을 측정하였다. 공칭 세공크기가 0.2μm, 외경이 6.4 또는 4.2 mm이고 육각 형태인 중공사형 모듈을 MLSS 8,000 mg/L 활성 슬러지 수용액에 각각 침지시키고 투과 유속, 공기량에 따른 변화를 확인하였다. 여과운전/정지이완(FR) 및 정지이완 시 역세척(FR/BW) 및 사인파형 투과유속 연속운전(SFCO) 방식으로 조작하였다. SFCO의 흡입 압력은 30 L/m2⋅hr에서 낮았으며, 50 L/m2⋅hr에서는 FR의 흡입 압력이 높게 나타났다. 또한 외경이 작은 모듈의 흡입 압력 상승이 비교적 낮았으며, 외경이 큰 모듈의 흡입 압력은 높게 상승하였지만 역세척으로 40% 이상 감소시킬 수 있었다.

This paper focuses on the simulation of refrigeration cycle equipped with the adiabatic capillary tube, which is widely used in small vapor compression refrigeration systems. The present simulation is based on fundamental conservation equations of mass, energy and momentum. These equations are solved through an iterative process. The adiabatic capillary tube model is based on homogeneous flow model. This model is used to understand the natural refrigerants flow behavior inside the adiabatic capillary tube. Transport properties and thermodynamic of natural refrigerants are calculated by using EES(Engineering Equation Solver) program. The operating factors considered in this paper include condensation temperature, evaporation temperature, inner diameter tube and sub-cooling degree of the adiabatic capillary tube. Our simulation results are summarized as follows: as the size of the inner diameter tube increases, the pressure drop in the capillary tube decreases while the length of the capillary tube increases. We found that R-290 decreases by 20-22% on average, and R-600a significantly decreases below 50%, while R-1270 increases 17-19% on average, compared to R-134a.

본 연구에서는 비용매 유도 상분리와 소결 공정을 혼용하여 기체 및 액체에 대하여 슈퍼플럭스 거동을 보이는 니켈 모세관 지지체를 성공적으로 제조하였다. 니켈 모세관 전구체는 니켈, 폴리술폰, DMAC, PEG를 이용하여 도프용액을 제 조한 후 NIPS 공정에 의하여 제조된 후에, 다양한 소결온도에서 수소 분위기 조건에서 소결하여 니켈 모세관 지지체를 제조 하였다. 최적의 니켈 모세관 지지체는 950°C 소결온도에서 얻어졌는데 외경 722 μm, 내경 550 μm, 두께 94 μm이었다. 니켈 모세관 지지체 기공율은 26%, 평균 기공경은 4 μm이었으며 3차원으로 서로 연결된 기공구조를 갖고 있었다. 그리고 파괴하 중은 2.84 kgf, 파괴 연신율은 13%이었다. 니켈 모세관 지지체의 He, N2, O2, CO2에 대한 단일 기체 투과도는 상온에서 각각 432,327, 281,119, 264,259, 193,143 GPU로 슈퍼플럭스 거동을 보였다. 이는 3차원적으로 서로 연결된 4 μm 크기 마크로기 공을 통하여 viscous flow가 일어났기 때문에 나타나는 현상으로 설명되었다.

A novel method for the detection of hydrogen peroxide in aqueous solution was developed via reaction between H2O2, trivalent titanium ion (Ti3+) and 4-(2-thiazolylazo) resorcinol (TAR), resulting in a ternary complex with a maximum UV absorbance at 530 nm. The CE detection of H2O2 was fast, sensitive and cost-effective without pretreatment procedures. H2O2 was detected within 15 min at 1 to 100 μM range with the lowest detection limit at 1.0 μM. Under the optimized CE conditions, the concentration of H2O2 in coffee or tea extract was quantitatively determined. Our results show that CE detection of the ternary complex of H2O2-Ti3+-TAR has potential applications for the detection of H2O2 in aqueous sources.

본 연구에서는 고투과성 Ni-ZiO2 모세관 지지체를 NIPS 방법에 의해서 제조되었으며, 기체분리용 고투과성 분리막 제조에 사용하고자 하였다. 이때 Ni:ZrO2 비율을 각각 100:0, 70:30, 50:50, 30:70으로 섞어 만든 도프용액을 이용하여 모세관 지지체를 제조한 후 소결온도를 950, 1000, 1100, 1200, 1300, 1400, 1500°C으로 달리하여 Ni:ZrO2 비율과 소결온도가 Ni-ZiO2 모세관 지지체의 기계적 안정성, 기공구조 및 단일기체투과도에 미치는 영향을 분석하고자 하였다.

The service life of coal gangue concrete(CGC) strongly depends on the capillary water absorption, this water absorption is susceptible to freeze-thaw cycles. In this paper, the cumulative water absorption and sorptivity were obtained to study the effects of 0, 0.5, 1.0, and 1.5 % steel fiber volume fraction added on the water absorption of CGC. Sorptivity and freeze-thaw tests were conducted, and the capillary water absorption was evaluated by the rate of water absorption(sorptivity). Three prediction models for the initial sorptivity of steel fiber reinforced coal gangue concrete(SFRCGC) under freeze-thaw cycles were established to evaluate the capillary water absorption of SFRCGC. Results showed that, without freeze-thaw cycles, the water absorption of CGC decreased when steel fiber at 1.0 % volume fraction was added, however, the water absorption increased with the addition of 0.5 or 1.5% steel fibers. Once the SFRCGC specimens were exposed to freeze-thaw cycles, the water absorption of SFRCGC significantly increased, and 1.0 % steel fiber in volume fraction added to CGC caused the lowest water absorption, except for the case of the sample without steel fibers added. The CGC with steel fiber at 1.0 % volume fraction performed better. The SFRCGC has a strong response to freeze-thaw cycles. Results also showed that the linear function prediction model is practical in the field of engineering because of its simple form and a relatively high precision. Although the polynomial prediction model presents the highest computation precision among the three models, the complicated form and too many coefficients make it impractical for engineering applications.

We demonstrate a simple and effective method to accurately position silicon nanowires (Si NWs) at desirable locations using drop-casting of Si NW inks; this process is suitable for applications in nanoelectronics or nanophotonics. Si NWs were assembled into a lithographically patterned sacrificial photoresist (PR) template by means of capillary interactions at the solution interface. In this process, we varied the type of solvent of the SiNW-containing solution to investigate different assembly behaviors of Si NWs in different solvents. It was found that the assembly of Si NWs was strongly dependent on the surface energy of the solvents, which leads to different evaporation modes of the Si NW solution. After Si NW assembly, the PR template was cleanly removed by thermal decomposition or chemical dissolution and the Si NWs were transferred onto the underlying substrate, preserving its position without any damage. This method enables the precise control necessary to produce highly integrated NW assemblies on all length scales since assembly template is easily fabricated with top-down lithography and removed in a simple process after bottom-up drop-casting of NWs.

The present study investigated the blood flow at microvascular network. The role of the blood viscosity and the yield stress of blood on the flow at the microvascular network was examined to find the condition of hemostasis. When the yield stress was less than 0.005Pa, there was no stagnant region in the capillary network used in the study. However, when the yield stress increased to 0.05Pa, stagnant areas began to appear, which grew and expanded rapidly with further increase in the yield stress. From the blood viscosity profile of a patient, one can estimate the yield stress of blood, from which the risk of hemostasis can be determined.