In this investigation, samples of the chemical (Hg1-xPbxBa2Ca1.8Mg0.2Cu3O8+δ) were prepared utilizing a solid-state reaction technique with a range of lead concentrations (x = 0.0, 0.05, 0.10, and 0.20). Specimens were pressed at 8 tons per square centimeter and then prepared at 1,138 K in the furnace. The crystalline structure and surface topography of all samples were examined using X-ray diffraction (XRD) and atomic force microscopy (AFM). X-ray diffraction results showed that all of the prepared samples had a tetragonal crystal structure. Also, the results showed that when lead was partially replaced with mercury, an increase in the lead value impacted the phase ratio, and lattice parameter values. The AFM results likewise showed excellent crystalline consistency and remarkable homogeneity during processing. The electrical resistivity was calculated as a function of temperature, and the results showed that all samples had a contagious behavior, as the resistivity decreased with decreasing temperature. The critical temperature was calculated and found to change, from 102, 96, 107, and 119 K, when increasing the lead values in the samples from 0.0 to 0.05, 0.10, and 0.20, respectively.

최근 여러 연구에서 Hg2+에 선택적으로 반응해 형광을 강화시키거나 소광시키는 thiophene을 기반으로한 probe가 많이 개발되어 왔지만, 이에 따른 분광학적 현상에 대한 정확한 분자적 수준의 이론적 해석이 이루어지지 않 았다. 이에 따라 우리는 Hg2+와 thiophene간 상호작용을 면밀히 분석하기 위해 Hg2+와 thiophene간 거리에 따른 에너 지 포텐셜을 구하였다. Hg2+ 이온에 대한 모든 전자(all electron, AE) basis set인 x2c-TZVPPall와 effective core potential (ECP) 기반인 LANL2DZ는 모두 상대성 효과가 고려된 바닥 상태에서 Hg2+와 thiophene이 결합력이 없이 해 리가 되는 에너지 포텐셜을 보여주었지만, 용매인 물이 고려된 시스템에서는 Hg2+와 thiophene이 결합력을 가지는 것 을 보였으며 이것은 실험적인 결과를 잘 재현하는 것이었다. 따라서 Hg2+ 이온을 포함하는 착화합물 시스템에서 올바 른 에너지 상태를 구하기 위해서는 상대성효과와 더불어 solvent 영향도 잘 고려돼야 함을 알 수 있다.

최근 우리는 Hg2+에 대한 높은 선택성을 가지며 Hg2+와 결합하여 밝은 녹색 형광을 보이는 tetraphenylethylene-bis(thiophen-2-ylmethyl)amine (TPE-BTA)의 착화합물(TPE-BTA-2Hg2+)의 구조를 밝혀내기 위해 시 간 의존적(time-dependent, TD) 밀도 함수 이론(DFT)을 이용하였다. 그러나 우리는 이 과정 속에서 Hg2+ 이온에 대한 모든 전자(all electron, AE) basis set인 x2c-TZVPPall만이 실험 스펙트럼에 가까운 흡수 및 형광 스펙트럼을 성공적으 로 재현한다는 것을 발견했다. 많이 알려져 있는 effective core potential (ECP) 기반인 LANL2DZ는 형광스펙트럼 계산 과 관련된 들뜬 상태의 구조 최적화 계산을 모두 실패했으며 또한, LANL2DZ는 첫 번째 들뜬 상태의 최적화 과정에서 너무 작은 형광 에너지를 제공했다. 이때 LANL2DZ는 리간드와 Hg2+ 사이의 거리가 증가함에 따라 빠르게 감소하는 HOMO-LUMO gap을 제공하는 반면, x2c-TZVPPall은 점진적으로 감소하는 안정적인 HOMO-LUMO gap을 보여줬다. 우리는 적어도 Hg2+ 이온을 포함하는 착화합물 시스템에서 ECP에서 발생하는 기하학적 문제들을 피하기 위해서는 모 든 전자 기본 세트를 사용하거나 새로운 ECP를 만들어야 된다고 조심스럽게 제안한다.

Activated carbon (AC) injection has been regarded as one of the most effective control technologies for Hg0 removal in flue gas. It is worthwhile to explore new and simple preparation methods for AC with low cost and high Hg removal capacity. In this study, a biomass based AC was successfully prepared from levant cotton exocarp using ZnCl2 activation. The mercury adsorption efficiency and mechanism were studied via the fixed bed experiments. Activator, reaction temperature and components of simulated coal-fired flue gas were investigated. Brunauer–Emmett–Teller (BET), scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM–EDX) and X-ray photoelectron spectroscopy (XPS) were applied for morphology characterization of the prepared AC and discussion of the possible adsorption mechanism. The adsorbed mercury species and the physiochemical properties of prepared AC were discussed. The results showed that (1) Hg0 removal efficiency could reach up to 90% at 150 ℃ under simulated flue gas (SFG); (2) Hg0 adsorption was controlled by the combination of physical and chemical mechanisms.

The aim of this work is to investigate the ability of a new functionalized graphene oxide 3-amino-5-phenylpyrazole (F-GO) in the adsorption and removal of Hg2+ from aqueous solution. Both untreated graphene oxide (GO) and F-GO were characterized using FT-IR, EDX, FE-SEM, XRD and TGA analysis. The effects of three operational variables (pH, adsorbent dose and initial metal ion concentrations) on Hg2+ adsorption capacity of F-GO were investigated by central composite design. This technique aims to find a simple way to optimize the adsorption process and to analyze the interaction between the significant parameters. A quadratic model suggested for the analysis of variance found that the adsorption of metal ions heavily depend upon pH of the solution. The adsorption mechanism has been determined by pseudo-first-order kinetic models and the adsorption behavior was modeled by Freundlich isotherm. Results demonstrated that the adsorption capacities of F-GO for removal of Hg2+ were generally higher than those of GO, which is attributed to a decrease in the agglomeration of graphene layers due to the presence of amino-functional moieties with their bulky phenyl groups. Thermodynamic data indicated that the functionalization significantly affects the thermostability of the GO precursor materials. The desorption study demonstrated favorable regenerability of the F-GO adsorbent, even after three adsorption–desorption cycles.

We develop a purification process of Hg2Br2 raw powders using a physical vapor transport(PVT) process, which is essential for the fabrication of a high performance acousto-optic tunable filter(AOTF) module. Specifically, we characterize and compare three Hg2Br2 powders: Hg2Br2 raw powder, Hg2Br2 powder purified under pumping conditions, and Hg2Br2 powder purified under vacuum sealing. Before and after purification, we characterize the powder samples through X-ray diffraction and X-ray photoelectron spectroscopy. The corresponding results indicate that physical properties of the Hg2Br2 compound are not damaged even after the purification process. The impurities and concentration in the purified Hg2Br2 powder are evaluated by inductively coupled plasma-mass spectroscopy. Notably, compared to the sample purified under pumping conditions, the purification process under vacuum sealing results in a higher purity Hg2Br2 (99.999 %). In addition, when the second vacuum sealing purification process is performed, the remaining impurities are almost removed, giving rise to Hg2Br2 with ultra-high purity. This high purification process might be possible due to independent control of impurities and Hg2Br2 materials under the optimized vacuum sealing. Preparation of such a highly purified Hg2Br2 materials will pave a promising way toward a high-quality Hg2Br2 single crystal and then high performance AOTF modules.

The use of microwave-assisted extraction and an acid-base clean-up process to determine the amount of methylmercury (MeHg) in marine products was suggested in order to improve the complicated sample preparation process. The optimal conditions for microwave-assisted extraction was developed by using a 10% NaCl solution as an extraction solution, setting the extraction temperature at 50℃, and holding for 15 minutes to extract the MeHg in marine products. A NaOH solution was selected as a clean-up substitute instead of L-cysteine solution. Overall, 670 samples of marine products were analyzed for total mercury (Hg). Detection levels were in the range of 0.0006~0.3801 μg/kg. MeHg was analyzed and compared using the current food code and the proposed method for 49 samples which contained above 0.1 mg/kg of Hg. Detection ranges of methylmercury followed by the Korea Food Code and the proposed method were 75.25 (ND~516.93) μg/kg and 142.07 (100.14~244.55) μg/kg, respectively. The total analytical time of proposed method was reduced by more than 25% compared with the current food code method.

Sulfur copolymer (poly(S-r-CEA)) was synthesized via facile inverse vulcanization of elemental sulfur with 2-carboxyethyl acrylate (CEA). Polysulfide (PS) oligomer was soluble to common solvents including DMF, producing homogenous dope solution with PAN as filler. PS-PAN was electrospun resulting to nanofiber membrane effective for Hg2+ sequestration with recorded maximum capacity of 612 mg g-1 based on Langmuir model isotherm. Kinetics, selectivity and reusability were also evaluated. This work presents new and cheap yet effective material for heavy metal sequestration from contaminated water. This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (2015R1A2A1A15055407) and by the Ministry of Education (No. 2009-0093816).

The clustered regularly interspaced short plalindromic repeats(CRISPR)/CRISPR associated protein (Cas9) system can be applied to produce transgenic pigs. We applied CRISPR/Cas9 system to generate hG-CSF targeted pig parthenogenetic embryos. Using sigle guided RNA targeted to pig hG-CSF genes was injected into cytoplasm of in vitro matured oocyte before electrical activation. The CRISPR/Cas9 vector were diluted in Tris-EDTA buffer (TE buffer) and injected with different concentration of 0 (sham injection), 2.5 and 25 ng/ul. In results, regardless of the concentrations of vector, the cleavage and blastocyst rate were not significantly different among three groups. Since plasmid DNA was used for microinjection, we investigated whether DNA vectors were integrated into the genome. Genomic PCR of the coding sequence of Cas9 variants and hG-CSF was performed to detect genomic integrants. Each blastocysts were collected into a microtube, and then PCR was performed. Overall 32 embryos are not expressed targeted gene.

산업화에 의해 발생되어진 여러 가지 오염물질 가운데 중금속인 니켈, 코발트, 수은은 연안 해역으로 유입 시 극히 미량일지라도 생체 내 축적되어 해양생물의 생리 및 발생에 장애를 일으키는 것으로 알려져 있으며 먹이연쇄 (food chain)를 통해 생물확대 (biomagnification)됨으로써, 해양생태계 전반에 영향을 미칠 수 있다. 본 연구는 유용 수산생물로써 조간대 암반 지역에 서식하는 말똥성게 (Hemicentrotus pulcherrimus)를 이용하여 니켈, 코발트, 수은의 생태 위해성을 조사하고자 한다. 성숙한 말똥성게 (H. pulcherrimus)에 0.5 M KCl를 주입하여 방란 및 방정을 유도한 후, 수집한 정자 및 난자를 니켈 (10, 25, 50, 100, 500 ppb), 코발트 (10, 100, 500, 1000, 2500 ppb) 그리고 수은 (10, 25, 50, 100, 500 ppb) 농도에서 10분간 인공수정 한 후, 수정 및 배아발생을 관찰하였다. 실험결과 수정률은 노출 된 각각의 니켈과 코발트 농도에 유의적인 영향을 받지 않았다. 수은은 농도가 증가할수록 농도 의존적으 로 감소하는 경향을 나타내었다. 배아 발생률은 니켈, 코발트 및 수은 농도가 증가 할수록 농도 의존적으 로 유의적인 감소를 나타내었다. 말똥성게 (H. pulcherrimus)의 배아 발생률에 대한 니켈, 코발트 및 수은 의 영향을 독성치로 나타냈을 때, 무영향농도 (NOEC)는 10 ppb로 모두 같은 값으로 나타났고, 최소영향 농도 (LOEC)는 각각 25 ppb, 10 ppb, 10 ppb로 나타났으며, 반수영향농도 (EC50)는 각각 34.19 ppb, 71.84 ppb, 144.66 ppb로 나타났다. 본 연구 결과, H. pulcherrimus의 배아 발생률을 이용한 생태독성 평가시, 니켈>코발트>수은 순으로 독성이 강한 것으로 나타났으며, 이들 중금속이 연안해역에 유입되어 10 ppb를 초과할 경우 연안 생태계 내에 서식하는 생물의 재생산에 유해한 영향을 미칠 것으로 판단된다.

본 연구에서는 hG-CSF의 발현을 유도적으로 조절하기 위한 FIV-Tet-On lentivirus vector system을 구축하고자 하였다. hG-CSF는 호중성구 계열 세포의 증식과 분화, 생존에 영향을 미치는 물질로서, 이 유전자의 발현을 증가시키기 위하여 FIV-Tet-On vector 상의 hG-CSF나 rtTA2SM2 서열의 3' 위치에 WPRE 서열을 도입하였다. 구축된 각각의 vector는 293FT 세포에 일시적으로 transfection하여 virus를 생산하였으며, 이 virus를 일차 배양 세포인 CEF와 PFF에 감염시켰다. 각 세포에 전이된 hG-CSF의 발현 양상을 관찰하기 위하여 doxycycline을 첨가하거나 첨가하지 않은 배지에서 배양한 후 quantitative real-time PCR, Western blot과 ELISA를 이용하여 hG-CSF 유전자의 발현 정도를 비교 측정한 결과, CEF에서는 WPRE가 hG-CSF의 3' 위치에 도입된 경우에 발현량과 유도율이 가장 높은 것으로 나타났고, PFF에서는 rtTA 서열의 3'위치에 도입된 경우에 발현량과 유도율이 가장 큰 것으로 확인되었다. 이 FIV-Tet-On vector system은 형질 전환 동물의 생산이나 유전자 치료에서 문제시되는 외래 유전자의 지속적인 과다 발현에 의한 개체의 생리적인 부작용을 최소화하기 위한 해결 방법으로 제시될 수 있을 것이다.

2001년 1-12월 서울시 가락농수산물시장에서 총 951건의 수산물(어류 34종 468건, 패류 17종 373건, 갑각류 10종 39건 그리고 두족류 등 11종 71건)을 대상으로 중금속 함량[average(minimum∼maximum), Unit:㎎/㎏]을 분석한 결과, Hg 0.025(N.D.∼0.19), Cd 0.288(N.D.∼1.85), pb 0.227(ND∼1.68)이었다. Hg의 경우, 패류[0.003((N.D.∼0.19)]>두족류 등[0.026(N.D.∼0.11)]>갑각류[0.026(N.D.∼0.09)]>어류[0.018(N.D.∼0.19)]순이었고, 가장 높은 함량은 미꾸라지(0.19)와 꼬막(0.19)이었으며, Pb의 경우 패류[0.223(N.D.∼1.38)]>어류[0.213(N.D.∼1.68)]>두족류 등[0.151(N.D.∼0.39)>갑각류[0.144(N.D.∼0.44)]순이었고, 가장 높은 함량은 미꾸라지(1.68)>빙어(1.44)>바지락(1.38)>뱀장어(1.35) 순이었다. 한편, Cd의 경우 패류[0.288(N.D.∼1.85)]중 가장 높은 함량은 꼬막(1.85)이었다.