Effect of oxidizing treatment on electrocatalytic activity of boron‑doped amorphous carbon thin films

Chen‑Song Wang,Ni Suo,Hao Huang,Ai‑min Wu,Guo‑Zhong Cao,Gui‑Feng Zhang 한국탄소학회 2019 Carbon Letters Vol.29 No.5

Boron-doped amorphous carbon (BDAC) thin films with a regular oxygen reduction reaction (ORR) catalytic activity were synthesized in a hot filament chemical vapor deposition device using a mixture of CH4 and H2 as a gas source and B2O3 as a boron source and then oxidized in air at 380–470 °C for 15–75 min. Scanning electron microscope, transmission electron microscope, Raman spectroscopy, X-ray photoelectron spectroscopy, and electrochemical tests were used to characterize the physical and electrochemical properties of the BDAC catalysts. It was concluded that the BDAC catalyst oxidized at 450 °C for 45 min showed the best ORR catalytic activity in alkaline medium. The oxygen reduction potential and the transfer electron number n, respectively, are − 0.286 V versus Ag/AgCl and 3.24 from the rotating disk electrode experiments. The treated carbon film has better methanol resistance and stability than the commercial Pt/C catalyst.

Synthesis and application of 8-hydroxyquinoline modified magnetic mesoporous carbon for adsorption of multivariate metal ions from aqueous solutions

Wenlu Guo,Xiangguo Meng,Yan Liu,Liang Ni,Zhaoyong Hu,Rui Chen,Minjia Meng,Yun Wang,Juan Han,Min Luo 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

The new 8-hydroxyquinoline (8-HQ) modified magnetic mesoporous carbon (8-HQ-Ni-CMK-3) wasprepared and applied for adsorption of multivariate metal ions from aqueous solution. The preparedadsorbent was characterized by Fourier transform infrared, X-ray diffraction, scanning electronmicroscopy, transmission electron microscope, nitrogen adsorption-desorption isotherm, elementalanalysis, and vibrating sample magnetometer. The static adsorption behaviors toward multivariatemetal ions on graphite, the modified graphite by 8-HQ, magnetic mesoporous carbon, and 8-HQ-Ni-CMK-3 were compared, which showed that 8-HQ-Ni-CMK-3 had excellent adsorption capacity. Theremoval of multivariate metal ions using 8-HQ-Ni-CMK-3 by fixed-bed column was further investigated.

Elevated thyroid hormones caused by high concentrate diets participate in hepatic metabolic disorders in dairy cows

Chen Qu,Wu Chen,Yao Zhihao,Cai Liuping,Ni Yingdong,Mao Shengyong 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.8

Objective: High concentrate diets are widely used to satisfy high-yielding dairy cows; however, long-term feeding of high concentrate diets can cause subacute ruminal acidosis (SARA). The endocrine disturbance is one of the important reasons for metabolic disorders caused by SARA. However, there is no current report about thyroid hormones involved in liver metabolic disorders induced by a high concentrate diet. Methods: In this study, 12 mid-lactating dairy cows were randomly assigned to HC (high concentrate) group (60% concentrate of dry matter, n = 6) and LC (low concentrate) group (40% concentrate of dry matter, n = 6). All cows were slaughtered on the 21st day, and the samples of blood and liver were collected to analyze the blood biochemistry, histological changes, thyroid hormones, and the expression of genes and proteins. Results: Compared with LC group, HC group showed decreased serum triglyceride, free fatty acid, total cholesterol, low-density lipoprotein cholesterol, increased hepatic glycogen, and glucose. For glucose metabolism, the gene and protein expression of glucose-6- phosphatase and phosphoenolpyruvate carboxykinase 1 in the liver were significantly up-regulated in HC group. For lipid metabolism, the expression of sterol regulatory element-binding protein 1, long-chain acyl-CoA synthetase 1, and fatty acid synthase in the liver was decreased in HC group, whereas carnitine palmitoyltransferase 1α and peroxisome proliferator activated receptor α were increased. Serum triiodothyronine, thyroxin, free triiodothyronine (FT3), and hepatic FT3 increased in HC group, accompanied by increased expression of thyroid hormone receptor (THR) in the liver. Conclusion: Taken together, thyroid hormones may increase hepatic gluconeogenesis, β-oxidation and reduce fatty acid synthesis through the THR pathway to participate in the metabolic disorders caused by a high concentrate diet. Objective: High concentrate diets are widely used to satisfy high-yielding dairy cows; however, long-term feeding of high concentrate diets can cause subacute ruminal acidosis (SARA). The endocrine disturbance is one of the important reasons for metabolic disorders caused by SARA. However, there is no current report about thyroid hormones involved in liver metabolic disorders induced by a high concentrate diet.Methods: In this study, 12 mid-lactating dairy cows were randomly assigned to HC (high concentrate) group (60% concentrate of dry matter, n = 6) and LC (low concentrate) group (40% concentrate of dry matter, n = 6). All cows were slaughtered on the 21st day, and the samples of blood and liver were collected to analyze the blood biochemistry, histological changes, thyroid hormones, and the expression of genes and proteins.Results: Compared with LC group, HC group showed decreased serum triglyceride, free fatty acid, total cholesterol, low-density lipoprotein cholesterol, increased hepatic glycogen, and glucose. For glucose metabolism, the gene and protein expression of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase 1 in the liver were significantly up-regulated in HC group. For lipid metabolism, the expression of sterol regulatory element-binding protein 1, long-chain acyl-CoA synthetase 1, and fatty acid synthase in the liver was decreased in HC group, whereas carnitine palmitoyltransferase 1α and peroxisome proliferator activated receptor α were increased. Serum triiodothyronine, thyroxin, free triiodothyronine (FT3), and hepatic FT3 increased in HC group, accompanied by increased expression of thyroid hormone receptor (THR) in the liver.Conclusion: Taken together, thyroid hormones may increase hepatic gluconeogenesis, β-oxidation and reduce fatty acid synthesis through the THR pathway to participate in the metabolic disorders caused by a high concentrate diet.

Parameter analysis of integral Fourier hologram and its resolution enhancement

Chen, Ni,Park, Jae-Hyeung,Kim, Nam The Optical Society 2010 Optics express Vol.18 No.3

<P>We present a parameter analysis of the integral Fourier hologram that is generated from multiple orthographic view images of a three-dimensional object. The maximum view angle, the lens array pitch, and the projection angle step are analyzed to reveal their effects on the maximum size of the reconstructed object and its maximum spatial frequency. With these analyses, we propose a lens array shift method to enhance the resolution of the reconstructed object from the Fourier hologram. The principles are verified by computational and optical experiment.</P>

Using Situational Simulation Nursing Guidance to Improve The Correct Rate of postoperative Wound Dressing For Elder Patients and Caregivers

Ni-Yuan Chen,Shu-Chuan Chiang 한국간호과학회 2019 한국간호과학회 학술대회 Vol.2019 No.10

Protein Kinase CK2 Modulates the Calcium Sensitivity of Type 3 Small-conductance Calcium-activated Potassium Channels in Colonic Platelet-derived Growth Factor Receptor Alpha-positive Cells From Streptozotocin-induced Diabetic Mice

Ni-Na Song,Xu Huang,Hong-Li Lu,Chen Lu,Jie Chen,Wen-Xie Xu 대한소화기 기능성질환∙운동학회 2023 Journal of Neurogastroenterology and Motility (JNM Vol.29 No.2

Background/AimsThe gastrointestinal symptom of diabetes mellitus, chronic constipation, seriously affects patients’ life. Whereas, the mechanism of chronic constipation is still ambiguous, resulting in a lack of effective therapies for this symptom. As a part of the smooth muscle cells, interstitial cells of Cajal, and platelet-derived growth factor receptor alpha-positive (PDGFRα+) cells syncytium (SIP syncytium), PDGFRα+ cells play an important role in regulating colonic motility. According to our previous study, in PDGFRα+ cells in colons of diabetic mice, the function of the P2Y1 purinergic receptor/type 3 small-conductance calcium-activated potassium (SK3) channel signaling pathway is strengthened, which may lead to colonic dysmotility. The purpose of this study is to investigate the changes in SK3 channel properties of PDGFRα+ cells in diabetic mice. MethodsWhole-cell patch clamp, Western blotting, superoxide dismutase activity measurement, and malondialdehyde measurement were main methods in the present study. ResultsThe present study revealed that when dialysed with low calcium ion (Ca2+) solution, the SK3 current density was significantly decreased in PDGFRα+ cells from diabetic mice. However, the SK3 current density in PDGFRα+ cells was enhanced from diabetic mice when dialysed with high Ca2+ solution. Moreover, hydrogen peroxide-treatment mimicked this phenomenon in SK3 transgenic HEK293 cells. The subunit of SK3 channels, protein kinase CK2, was up-regulated in colonic muscle layers and hydrogen peroxide-treated HEK293 cells. Additionally, protein phosphatase 2A, the subunit of SK3 channels, was not changed in streptozotocin-treated mouse colons or hydrogen peroxide-treated HEK293 cells. ConclusionThe diabetic oxidative stress-induced upregulation of CK2 contributed to modulating SK3 channel sensitivity to Ca2+ in colonic PDGFRα+ cells, which may result in colonic dysmotility in diabetic mice.

Numerical and experimental method for the prediction of the propagation life of fatigue crack on metallic materials

Chen Ni,Lin Hua,Xiaokai Wang,Zhou Wang,Zhikui Ma 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.9

A prediction method for the propagation life of fatigue crack for cracked components was provided and verified in this study to predict the propagation life of fatigue cracks on components in engineering applications conveniently and directly. In the simulation aspect, a finite element (FE) model of cracked specimen was created to obtain the stress intensity factor range ΔK. The FE model was verified by comparing simulated ΔK to a formulary calculated one. The simulated ΔK could be used for studying the relationship with crack size. In the experimental aspect, the fatigue crack propagation test was conducted on three specimens. The material coefficients C and m were fitted according to Paris’ law. The load cycles with different crack depths were recorded in the testing process. The propagation life of fatigue cracks of specimen was predicted via the relationship between ΔK and crack size a according to Paris’ law. The comparison between predicted life and experimental life of specimens indicated the feasibility of the method. The proposed prediction method in this study for the propagation life of fatigue cracks can be used in engineering applications.

Metal-Doped In2O3 Nanosphere Arrays with Enhanced Gas-Sensing Property

Xuanji Zhang,Ni Deng,Xianjia Chen,Yanting Yang,Jing Li,BO HONG,DINGFENG JIN,Xiaoling Peng,XINQING WANG,Hongliang Ge,HONGXIAO JIN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.3

In2O3 and metal-doped (Ni or Ce) In2O3 mesoporous three-dimensional (3D) nanospheres arrays were synthesized via nanocasting using mesoporous silica as hard templates. Effects of Ni or Ce doping on the structure, optical and gas-sensing properties of the In2O3 nanospheres were investigated. Both the undoped and the doped In2O3 nanospheres showed single-phase structure without any impurity. The nanospheres were about 20 nm in size and they stacked closely to formrigid 3D mesoporous structure. Achange in the value of optical band gap was observed upon metal doping. The room temperature photo luminescence behavior also showed some differences between pure and doped In2O3. Compared with pure In2O3 nanospheres, the metal-doped In2O3 exhibited superior response, fast recovery and good selectivity to ethanol. The enhanced gas-sensing properties might be related to the doping of metal ion and its effective contribution towards the oxygen vacancies, conductivity and crystallite size of the grains.

STANCU TYPE GENERALIZATION OF MODIFIED GAMMA OPERATORS BASED ON q-INTEGERS

Chen, Shu-Ni,Cheng, Wen-Tao,Zeng, Xiao-Ming Korean Mathematical Society 2017 대한수학회보 Vol.54 No.2

In this paper, we propose the Stancu type generalization of a kind of modified q-Gamma operators. We estimate the moments of these operators and give the basic convergence theorem. We also obtain the Voronovskaja type theorem. Furthermore, we obtain the local approximation, rate of convergence and weighted approximation for these operators.

Resolution enhanced Fourier Hologram using integral imaging with lens array shifting

Ni Chen,Jae-Hyeung Park,Nam Kim,Seok-Hee Jeon 한국통신학회 2009 한국통신학회 워크샵 Vol.2009 No.6

We propose a method to enhance the resolution ortlle 3D object reconstruction from its Fourier hologram. In this method we capture the 3D object by using a lens array, and we shift the lens array to three directions, i.e. left, top, and left top. In addition to the conventional one, we get four sets of element images. Using these four sets of element images, we synthesize one set of clcment images. From this synthesized element image we get the orthographic images. Since the number of the element images is four times to the conventional one, the resolution of the orthographic image is increased. Then we generate Fourier hologram from the high resolution orthographic image. Finally we reconstruct the 3D object from the Fourier hologram. The resolution of the reconstruction object is enhanced due to the high resolution of the Fourier hologram. We verified the method experimentally.