Methane production from carbon monoxide and hydrogen over nickel-alumina xerogel catalyst: Effect of nickel content

Hwang, S.,Lee, J.,Hong, U.G.,Seo, J.G.,Jung, J.C.,Koh, D.J.,Lim, H.,Byun, C.,Song, I.K. Korean Society of Industrial and Engineering Chemi 2011 Journal of industrial and engineering chemistry Vol.17 No.1

Nickel-alumina xerogel catalysts (XNiAl) with different nickel contents (X, wt%) were prepared by a single-step sol-gel method for use in the methane production from carbon monoxide and hydrogen. The effect of nickel content on the catalytic performance of XNiAl catalysts was investigated. Conversion of CO and yield for CH<SUB>4</SUB> over XNiAl catalysts drastically increased with increasing nickel content from 20 to 40wt%, but they were almost constant at nickel content above 40wt%. This indicates that XNiAl catalysts with nickel content above 40wt% served as efficient catalysts in the methane production from carbon monoxide and hydrogen. The enhanced catalytic performance of nickel-alumina xerogel catalysts with nickel content above 40wt% was attributed to the abundant active surface nickel species caused by well-developed framework mesopores and large pore size of the catalysts. When considering the amount of nickel used for the preparation of catalyst, it is reasonable to conclude that the optimal nickel content of nickel-alumina xerogel catalyst for methanation reaction was 40wt%.

Methane production from carbon monoxide and hydrogen over nickel–alumina xerogel catalyst: Effect of nickel content

Sunhwan Hwang,송인규,Joongwon Lee,Ung Gi Hong,Jeong Gil Seo,정지철,고동준,Hyojun Lim,Changdae Byun 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.1

Nickel–alumina xerogel catalysts (XNiAl) with different nickel contents (X, wt%) were prepared by a single-step sol–gel method for use in the methane production from carbon monoxide and hydrogen. The effect of nickel content on the catalytic performance of XNiAl catalysts was investigated. Conversion of CO and yield for CH4 over XNiAl catalysts drastically increased with increasing nickel content from 20 to 40 wt%, but they were almost constant at nickel content above 40 wt%. This indicates that XNiAl catalysts with nickel content above 40 wt% served as efficient catalysts in the methane production from carbon monoxide and hydrogen. The enhanced catalytic performance of nickel–alumina xerogel catalysts with nickel content above 40 wt% was attributed to the abundant active surface nickel species caused by welldeveloped framework mesopores and large pore size of the catalysts. When considering the amount of nickel used for the preparation of catalyst, it is reasonable to conclude that the optimal nickel content of nickel–alumina xerogel catalyst for methanation reaction was 40 wt%.

Nickel induces secretion of IFN-γ by splenic natural killer cells

Ji-Yeon Kim,Kyungmin Huh,이기영,Jun-Mo Yang,김태진 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.4

Although nickel hypersensitivity is known as a delayed- type hypersensitivity mediated by nickel-specific T cells, it is greatly influenced by other immune cells. Here we show that splenic natural killer cells (NK cells) directly or indirectly respond to nickel by secretion of IFN-γ. Using enzyme-linked immunosorbent spot (ELISPOT) assays, we found that nickel-reactive cells readily secreted IFN-γ when splenocytes were cultured in the presence of varying concentrations of nickel sulfate (NiSO4) for 24 h. However, nickel-reactive IL-2- or IL- 4-secreting cells were infrequent during the 24-h culture with NiSO4. Immune responses to nickel were innate, not adaptive, in nature since the frequency of nickel-reactive IFN-γ-secreting cells did not increase upon previous exposure to NiSO4 and recombination activating gene (RAG)-1-deficient mice contained nickel-reactive IFN-γ-secreting cells. The involvement of NK cells in the innate response to NiSO4 was confirmed since we could observe a significant reduction of the frequency of nickel-reactive cells in NK cell-depleted mice. Furthermore, the number of IFN-γ secreting cells was significantly reduced in the ELISPOT assays when NKG2D was blocked by anti-NKG2D antibody. These results suggest that there is an early and rapid innate immune response to nickel, which is mediated by NK cells and the NKG2D receptor. The significance of the innate response to nickel is that it may contribute to development of the late T cell-mediated delayed type hypersensitivity against nickel.

FC 1-1 : Clinical outcome of nickel alloy-based atrial septal defect occluder implantation in nickel allergy patients

( Hee Joo Kim ),( Jung U Shin ),( Jung Soo Lee ),( Hemin Lee,Ji ),( Yeon Noh ),( Jin Shan ),( Suh Hyung Kim ),( Kwang Hoon Lee ) 대한피부과학회 2014 대한피부과학회 학술발표대회집 Vol.66 No.2

Background: There is controversy over a need for patch test to rule out possible metal allergy-related complications prior to implantation of devices made of nickel alloy. Objectives: To evaluate the prevalence and characteristics of potential adverse events including nickel toxicity in patients who underwent atrial septal defect (ASD) closure with nickel-titanium alloy-based device in a single institution. Methods: We retrospectively reviewed the medical records of patients who underwent ASD closure with nitinol device and evaluated adverse events during a follow-up period. Results: Among 38 patients, 5 patients had symptomatic nickel allergy proven by patch test. Four nickel-allergic patients had post-closure complications, including chest discomfort and migraine headache beginning within 1 month. Ten of 33 non-nickel-allergic patients had adverse symptoms, including chest tightness, dyspnea, and migraine. All adverse events occurred within 1 month post-procedure, and lasted for less than 1 year except for 1 nickel-allergic patient. A longer follow-up (24.1±3.2 months) indicated no additional development of symptoms. Conclusion: In this study, positive reactions to nickel on patch test were not associated with adverse early or late outcomes. Patch test might be a valuable ancillary tool to detect nickel allergy, but the usefulness to predict long-term result of occlusion is indecisive and not obligatory for patients prior to ASD occlusion with nickel-alloy based devices.

니켈 알레르기 환자에서 한국 니켈 제한 식이의 효과와 환자 순응도에 관한 고찰

김로사 ( Rosa Kim ),이민영 ( Min Young Lee ),변지연 ( Ji Yeon Byun ),최유원 ( You Won Choi ),최혜영 ( Hae Young Choi ) 대한피부과학회 2021 대한피부과학회지 Vol.59 No.9

Background: Nickel is one of the leading causes of allergic contact dermatitis. Positive patch tests for nickel suggest the possibility of persistent dermatitis from nickel-plated item usage and nickel-containing food ingestion. Previous studies have suggested the clinical improvement of dermatitis in such patients after a nickel-restricted diet. Objective: This retrospective study aimed to assess the efficacy of nickel-restricted diets in nickel-sensitized patients and evaluate their adherence to nickel-restricted diets. Methods: A review of the records of nickel-sensitized patients from June 1, 2018 to April 30, 2020 with positive patch tests for nickel was conducted. Patients were interviewed in May 2020 to assess the current status of dermatitis and self-reported adherence. Results: A total of 245 patients were identified, and 100 patients were contacted. The degree of nickel sensitivity between patients with localized skin lesions (n=44) and generalized skin lesions (n=56) did not show difference. Twenty-four of 29 patients (82.8%) with good compliance showed improvement, while only 32 of 71 patients (45.1%) with poor compliance showed improvement. The percentage of improved patients in the group with good compliance and that in the group with poor compliance showed a statistically significant difference (p=0.00086). Of the patients with good compliance, those with localized skin lesions showed statistically significant improvement (p=0.0074). Conclusion: To improve patient compliance, revised, simplified, and interventional guidelines for nickel-restricted diet should be implemented along with dermatologists’ encouragement and reassurance of a diet modification. (Korean J Dermatol 2021;59(9):713∼719)

Assessment of efficacy and adherence of nickel restricted diet in nickel allergic patients

( Rosa Kim ),( Min Young Lee ),( Ji Yeon Byun ),( You Won Choi ),( Hae Young Choi ) 대한피부과학회 2020 대한피부과학회 학술발표대회집 Vol.72 No.1

Background: Nickel is contained in everyday objects, and it is one of the leading causes of allergic contact dermatitis. Positive patch tests to nickel suggest possibility of dermatitis from nickel-plated item usage and nickelcontaining- food ingestion. Objectives: This was a retrospective study to assess efficacy of nickel restricted diets in nickel sensitized patients and to evaluate their adherence to nickel restricted diet. Methods: A review of the records of nickel sensitized patients from June 1st 2018 to April 30th 2020 with positive patch tests to nickel was conducted. Patients were phone interviewed in May 2020 to assess current status of their dermatitis, frequency of flare-up, and self-reported adherence to the diet. Results: Of 245 patients, only 100 patients were able to be contacted. Patients with localized skin lesion (n=44) and with generalized skin lesion (n=56) did not show difference in nickel sensitivity. The extent of involved skin lesion and nickel sensitivity did not predict compliance. 24 of 29 (82.7%) patients with good compliance reported improvement; only 32 of 71 (45.1%) patients with poor compliance reported improvement. The percentage of improved patients with good compliance and that of the group with poor compliance showed statistically significant difference (p<0.05). Conclusion: To improve patient compliance, a simplified and interventional guidelines for nickel restricted diet should be implemented along with dermatologists’ encouragement and reassurance.

식품 내 니켈 함량 분석에 기반한 한국 니켈 제한 식이

이진주,김로사,이희라,변지연,최유원,노주영,최혜영 대한피부과학회 2024 대한피부과학회지 Vol.62 No.2

Background: Nickel is a leading cause of allergic contact dermatitis. Patients with nickel allergy may suffer from persistent dermatitis not only through contact with nickel-plated items but also through ingestion of nickel-containing food. Objective: This study aimed to evaluate the current nickel content in Korean food products and provide more up-to-date Korean nickel-restricted diets that would increase patient compliance. Methods: The most frequently consumed food items were selected with replicates. Food samples were prepared according to the practices of normal consumers. The solid specimens were finely ground, and the liquid specimens were homogenized using a sterilized mixer. Tea bags were brewed in 100 mL of distilled water at 100 °C for 5 minutes. Solid (0.5 g) and liquid (2 g) specimens were subjected to microwave-assisted nitric acid digestion using inductively coupled plasma-mass spectrometry. Results: In total, 147 samples were collected from different food categories, including plant-based products, animal-based products, packaged foods, and drinks. Cocoa powder had the highest concentration of nickel (1.56 mg/kg), which is consistent with the results of previous studies. Soy products such as fermented soybean paste (Doenjang) (1.16 mg/kg), fermented soybean with red chili paste (Ssamjang) (0.67 mg/kg), and tofu (0.37 mg/kg) had elevated concentration of nickel. Moreover, nut-derived products such as chocolate (1.10 mg/kg), ground coffee (0.86 mg/kg), almond (0.84 mg/kg), and peanuts (0.64 mg/kg) contained elevated nickel concentration. Conclusion: The nickel content in food constantly changes depending on the food processing procedures and place of origin. Therefore, revising the nickel-restricted diet is necessary to enhance patients’ understanding of it and help reduce dietary nickel intake.

니켈-티타늄 와이어의 열처리에 따른 부하-변위 특성 변화

장수호,임성훈,김광원 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.5

니켈-티타늄 합금은 높은 spring-back 성질, 초탄성 효과, 형상기억 효과 등의 장점을 가지고 있으나 성형이 어렵다는 단점을 가지고 있다. 본 연구에서는 니켈-티타늄 와이어의 굴곡을 위한 열처리 시에 나타나는 부하-변위 곡선의 변화 및 상전이 온도 변화와 같은 물성 변화 양상을 조사하고자 하였다. 수종의 니켈-티타늄 와이어를 열처리를 시행하지 않은 군, 전기저항 열처리 장치를 이용하여 와이어 단면적에 따라 제조회사에서 권장하는 전류를 기초로 하여 00.016" ×00.022" (5 A, 7 sec), 0.018" × 0.025" (6 A, 7 sec) 그리고 0.0215" × 0.028" (7 A, 8 sec) 와이어를 열처리만 시행한 실험군, 열처리를 시행하여 굴곡을 부여한 실험군 그리고 열처리 시간을 1초 증가시켜 굴곡을 부여한 실험군으로 분류하여 3점 굴곡 실험과 시차주사열량측정을 하여 다음과 같은 결과를 얻었다. 0.016" × 0.022", 0.018" × 0.025" 그리고 0.0215" × 0.028" 니켈-티타늄 와이어에서 굴곡을 부여하지 않고 열처리만 시행한 실험군이 열처리를 시행하지 않은 대조군에 비해 부하-변위 곡선이 상방 이동되어 초탄성 현상에 의한 평탄역(loading and unloading plateau)의 힘이 더 증가되었다. 0.016" × 0.022", 0.018" × 0.025" 그리고 0.0215" × 0.028" 와이어에서 열처리만 시행한 실험군이 열처리를 시행하지 않은 군보다 더 낮은 austenite finish (A_(f)) 온도를 보였다, 0.018" × 0.025" 및 0.0215" × 0.028" 와이어에서 열처리를 시행하여 굴곡을 부여한 실험군은 열처리만 시행한 실험군과 열처리를 시행하지 않은 대조군에 비해 부하-변위 곡선이 상방 이동되었으며, 열처리 시간을 1초 증가시켜 굴곡을 부여한 실험군에서 가장 높은 부하-변위 곡선을 나타냈다. 0.018" × 0.025" 그리고 0.0215" × 0.028" 와이어에서 A_(f) 온도는 열처리 시간을 1초 증가시켜 굴곡을 부여한 실험군에서 가장 낮게 관찰되었고 열처리를 시행하여 굴곡을 부여한 실험군, 열처리만 시행한 실험군 그리고 열처리를 시행하지 않은 대조군 순으로 높게 관찰되었다. 이상의 결과를 종합할 때, 임상에서 니켈-티타늄 합금 와이어에 굴곡을 부여하기 위해 열처리하는 경우 초탄성 특성은 유지될 수 있으나, 부하-변위 곡선의 상방 증가가 나타나므로, 와이어에 의한 교정력이 증가될 수 있음에 유의하여야 한다. Objective: Nickel-titanium alloy wire possesses excellent spring-back properties, shape memory and super-elasticity. In order to adapt this wire to clinical use, it is necessary to bend as well as to control its super-elastic force. The purpose of this study is to evaluate the effects of heat treatment on the load-deflection properties and transitional temperature range (TTR) of nickel-titanium wires. Methods: Nickel-titanium wires of different diameters (0.016" × 0.022", 0.018" × 0.025" and 0.0215" × 0.028") were used. The samples were divided into 4 groups as follows: group 1, posterior segment of archwire (24 mm) without heat treatment; group 2, posterior segment of archwire (24 mm) with heat treatment only; group 3, anterior segment with bending and heat treatment; group 4, anterior segment with bending and 1 sec over heat treatment. Three point bending test was used to evaluate the change in load-deflection curve and obtained DSC (different scanning calorimetry) to check changes in A_(f) temperature. Results: In the three point bending test, nickel-titanium wires with heat treatment only had higher load-deflection curve and loading and unloading plateau than nickel-titanium wires without heat treatment. Nickel-titanium wires with heat treatment had lower Af temperature than nickel-titanium wires without heat treatment. Nickel-titanium wires with heat treatment and bending had higher load-deflection curve than nickel-titanium wires with heat treatment and nickel-titanium wires without heat treatment. Nickel-titanium with heat treatment of over 1 sec and bending had the highest load-deflection curve. Nickel-titanium wires with heat treatment and bending had lower Af temperature, Nickel-titanium wires with heat treatment of over 1 sec and bending had the lowest Af temperature. Conclusion: From the results of this study, it can be stated that heat treatment for bending of Nickel-titanium wires does not deprive the superelastic property but can cause increased force magnitude due to a higher load-deflection curve.

수열합성된 나노구조 니켈/니켈 수산화물의 상과 형태 및 슈퍼커패시터 적용

엄승용,정진주,김도형 한국물리학회 2021 새물리 Vol.71 No.6

Urchin-like nanostructured nickel/nickel hydroxides (NNHO) were successfully synthesized by using the hydrothermal method, and the phase and the morphology of the nanostructured nickel/nickel hydroxide were controlled by using different synthesis temperatures. The diameter of the nanostructured NNHO synthesized at a relatively high temperature wes bigger than that of the samples synthesized at low temperature, which could be explained by using Ostwald ripening. The phase of the as-synthesized nanostructure was composed of crystalline metallic nickel on the inside and amorphous nickel hydroxide on the surface. To compare the electrochemical properties, the as-synthesized samples are converted to nickel oxide (NO) by annealing at different temperatures. The as-synthesized NNHO showed the highest specific capacitance, as well as easy electrolyte accessibility, because NNHO had not only an easily accessible nanostructure but also the synergistic effect of crystalline nickel and amorphous nickel hydroxide. The present work can contribute to the synthesis of nanostructured NNHO and to the applications of supercapacitors using heterostructure materials. 성게 모양의 나노구조 니켈/니켈 수산화물(NNHO)을 수열합성법으로 합성하였다. 나노구조 NNHO의상과 형태는 합성 온도와 합성 후 열처리 온도에 의해 조절되었다. 상대적으로 고온에서 합성된 나노구조NNHO의 직경은 저온에서 합성된 샘플보다 직경이 크고, 이는 오스트발트 숙성 (Ostwald ripening)에의해 설명된다. 합성된 나노구조 NNHO의 상은 내부의 결정성 금속 니켈과 표면의 비정질 니켈 수산화물로구성된다. 전기화학적 특성을 비교하기 위해, 합성된 NNHO를 열처리하여 니켈 산화물(NO)로 상전이시켰다. 순환전압전류법 및 정전류 충방전 측정 결과, 합성된 NNHO가 NO에 비해서 더 높은 전기용량과쉬운 전해질 접근성을 보였으며, 이것은 NNHO가 쉽게 접근 가능한 나노구조를 가질 뿐만 아니라 결정질니켈과 비결정질 니켈 수산화물의 시너지 효과 (synergistic effect) 에 의한 것이다. 이 연구는 나노구조 NNHO의 합성과 이종 구조 물질을 활용한 슈퍼커패시터 응용 연구에 기여할 수 있을 것으로 기대된다.

Steam reforming of liquefied natural gas (LNG) for hydrogen production over nickel–boron–alumina xerogel catalyst

Park, Seungwon,Yoo, Jaekyeong,Han, Seung Ju,Song, Ji Hwan,Lee, Eo Jin,Song, In Kyu Pergamon Press 2017 International journal of hydrogen energy Vol.42 No.22

<P><B>Abstract</B></P> <P>A series of mesoporous nickel–boron–alumina xerogel (<I>x</I>-NBA) catalysts with different boron/nickel molar ratio (<I>x</I> = 0–1) were prepared by an epoxide-driven sol–gel method. The effect of boron/nickel molar ratio on the catalytic activities and physicochemical properties of nickel–boron–alumina xerogel catalysts was investigated in the steam reforming of liquefied natural gas (LNG). All the mesoporous <I>x</I>-NBA catalysts showed similar surface area. Introduction of boron increased interaction between nickel and support. In addition, introduction of boron into <I>x</I>-NBA catalysts reduced methane activation energy and increased nickel surface area. Promotion of boron had a positive effect on the catalytic activity due to the increase of adsorbed methane and nickel surface area. The amount of adsorbed methane and nickel surface area exhibited volcano-shaped trends with respect to boron/nickel molar ratio. LNG conversion and hydrogen yield increased with increasing the amount of adsorbed methane and with increasing nickel surface area. Among the catalysts, 0.3-NBA, which retained the largest amount of adsorbed methane and the highest nickel surface area, showed the best catalytic performance. It was also revealed that <I>x</I>-NBA catalysts showed strong coke resistance during the steam reforming reaction.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ni–B–Al<SUB>2</SUB>O<SUB>3</SUB> (<I>x</I>-NBA) catalysts with different B/Ni molar ratio (<I>x</I> = 0–1) were prepared. </LI> <LI> Hydrogen was produced by steam reforming of liquefied natural gas (LNG). </LI> <LI> Hydrogen yield increased with increasing the amount of adsorbed methane. </LI> <LI> Hydrogen yield increased with increasing nickel surface area. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>