Catalytic reduction of CO2 to HCO2 by nanoscale nickel-based bimetallic alloy under atmospheric pressure

Yi Zhao,Tianhao Wang,Yongbin Wang,Runlong Hao,Han Wang,Yuhong Han 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.77 No.-

Carbon dioxide (CO2) was converted into formate (HCO2) in a catalytic reduction system mainlycomposed of potassium borohydride (KBH4) and nanoscale bimetallic nickel–copper alloy (NBN–C), inwhich, the average CO2 conversion efficiency of 41.92% was obtained under the optimal experimentalconditions, with a HCO2selectivity of 53.42%. Various characterization methods were employed toinvestigate the physicochemical properties of NBN–C and the results indicated that NBN–C was a coreshellmesoporous catalyst with key active sites containing Ni0 and Cu0, at which the catalytic reduction ofCO2 took place. The reaction mechanism was proposed based on these characterizations and relevantliteratures.

Phase Stability and Thermo-Physical Properties of Nickel-Aluminum Binary Chemically Disordered Systems via First-Principles Study

Zhiqin Wen,Yuhong Zhao,Jianhua Li,Hua Hou 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.6

The effect of Al content and crystal structures on ground state, phase stability, elasticity and thermodynamics of Ni1−xAlx(x = 0.25, 0.50 and 0.75) binary chemically disordered systems are investigated using first-principles method in combinationwith quasi-harmonic Debye-Grüneisen model. The special quasirandom structures are applied to model disordered bodycenteredcubic (bcc) and face-centered cubic (fcc) phases. The Gibbs free energy of mixing of equiatomic Ni0.5Al0.5is thelowest. The nonmagnetic fcc structure’ Ni1−xAlx are predicted to be more favorable phases. Disordered Ni1−xAlx are lessstable than ordered L21Ni3Aland B2 NiAl, and L21phase is the most likely to form a nuclear growth. The somewhat differentimpact of Al content on elastic properties has been extracted that the resistance to volume change, shear deformation andelastic deformation of Ni1−xAlx decrease with increasing Al content. For bcc and fcc phases, Ni0.75Al0.25and Ni0.25Al0.75arepredicted to be ductile behavior, while Ni0.5Al0.5exhibit brittleness. The structural, vibrational and electronic contributionsare taken into account to study the thermodynamic properties at finite temperature. The lattice constants a and volumetricthermal expansion coefficient α of Ni1−xAlx systems increase with the increase of Al content. Nevertheless, it is decreasingfor heat capacity Cv and Cvvib. The vibrational entropy Svib of bcc Ni0.25Al0.75is the largest in considered temperature. The α,Cvvib and Svib of disordered Ni1−xAlx are larger than that of ordered Ni3Aland NiAl. Vibrational and electronic entropy arethe dominating at finite temperature stabilization mechanism.

Changes in Protein Phosphorylation during Salivary Gland Degeneration in Haemaphysalis longicornis

Qi Xiao,Yuhong Hu,Xiaohong Yang,Jianna Tang,Xiaoshuang Wang,Xiaomin Xue,Mengxue Li,Minjing Wang,Yinan Zhao,Jingze Liu,Hui Wang 대한기생충학ㆍ열대의학회 2020 The Korean Journal of Parasitology Vol.58 No.2

The ticks feed large amount of blood from their hosts and transmit pathogens to the victims. The salivary gland plays an important role in the blood feeding. When the female ticks are near engorgement, the salivary gland gradually loses its functions and begins to rapidly degenerate. In this study, data-independent acquisition quantitative proteomics was used to study changes in the phosphorylation modification of proteins during salivary gland degeneration in Haemaphysalis longicornis. In this quantitative study, 400 phosphorylated proteins and 850 phosphorylation modification sites were identified. Trough RNA interference experiments, we found that among the proteins with changes in phosphorylation, apoptosis-promoting Hippo protein played a role in salivary gland degeneration.

Evaluating fermentation quality, in vitro digestibility and aerobic stability of a total mixed ration ensiled with different additives on Tibet plateau

Dong, Zhihao,Wang, Siran,Zhao, Jie,Li, Junfeng,Liu, Qinhua,Bao, Yuhong,Shao, Tao Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.2

Objective: To investigate the improvement in utilization efficiency of total mixed ration (TMR) on Tibetan plateau, TMR were ensiled with different additives. Methods: A total of 150 experimental silos were prepared in a completely randomized design to evaluate the six treatments: i) control (without additive), ii) Lactobacillus buchneri (L. buchneri), iii) acetic acid, iv) propionic acid, v) 1,2-propanediol; and vi) 1-propanol. After 90 days of ensiling, silos were opened for fermentation quality and in vitro analysis, and then subjected to an aerobic stability test for 14 days. Results: Treating with L. buchneri, acetic acid, 1,2-propanediol and 1-propanol decreased propionic acid contents and yeast number, whereas increased (p<0.05) pH, acetic acid and ethanol contents in the fermented TMR. Despite increased dry matter (DM) loss in the TMRs treated with 1,2-propanediol and 1-pronanol, additives did not affect (p>0.05) all in vitro parameters including gas production at 24 h (GP24), GP rate constant, potential GP, in vitro DM digestibility and in vitro neutral detergent fibre digestibility. All additives improved the aerobic stability of ensiled TMR to different extents. Specially, aerobic stability of the ensiled TMR were substantially improved by L. buchneri, acetic acid, 1,2-propanediol, and 1-propanol, indicated by stable pH and lactic acid content during the aerobic stability test. Conclusion: L. buchneri, acetic acid, 1,2-propanediol, and 1-propanol had no adverse effect on in vitro digestibility, while ensiling TMR with the additives produced more acetic acid and ethanol, subsequently resulting in improvement of aerobic stability. There is a potential for some fermentation boosting additives to enhance aerobic stability of fermented TMR on Tibetan plateau.

Novel Method to Improve the Microstructure and Mechanical Properties of 45 Steel

Tao Gu,Shuaixin Zhang,Yuhong Zhao,Yurong Yang,Huafeng Liu,Li Wu,Jianhua Liu,Hua Hou 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.4

Aiming at the problems of poor hardenability and low mechanical strength of 45 steel after quenching and tempering atnormal pressure, 45 steel was quenched and tempered under high pressure. The microstructure of 45 steel after high pressurequenching and tempering was analyzed by optical microscope, scanning electron microscope and transmission electronmicroscope, its hardness and compressive strength were tested by hardness tester and electronic universal testing machine,and compared with samples treated by the same process under atmospheric pressure. The results show that uniform andcompact tempered sorbite can be obtained after high pressure quenching and tempering of 45 steel, and the precipitatedgranular carbides are finely dispersed, thus improving the mechanical properties of 45 steel. Under a pressure of 3 GPa,quenching at 900 °C for 15 min and 550 °C for 60 min tempering, the hardness and compressive yield strength of 45 steelwere 36.3 HRC and 971 MPa, respectively, which were respectively 25.17% and 20.77% higher than the corresponding valuesobtained with the same process under atmospheric pressure quenching and tempering. This work provides a new method toeffectively improve the mechanical properties of 45 steel.

A polymeric composite protective layer for stable Li metal anodes

Guo Suogang,Wang Li,Jin Yuhong,Piao Nan,Chen Zonghai,Tian Guangyu,Li Jiangang,Zhao Chenchen,He Xiangming 나노기술연구협의회 2020 Nano Convergence Vol.7 No.21

Lithium (Li) metal is a promising anode for high-performance secondary lithium batteries with high energy density due to its highest theoretical specific capacity and lowest electrochemical potential among anode materials. However, the dendritic growth and detrimental reactions with electrolyte during Li plating raise safety concerns and lead to premature failure. Herein, we report that a homogeneous nanocomposite protective layer, prepared by uniformly dispersing ­AlPO 4 nanoparticles into the vinylidene fluoride-co-hexafluoropropylene matrix, can effectively prevent dendrite growth and lead to superior cycling performance due to synergistic influence of homogeneous Li plating and electronic insulation of polymeric layer. The results reveal that the protected Li anode is able to sustain repeated Li plating/stripping for > 750 cycles under a high current density of 3 mA cm −2 and a renders a practical specific capacity of 2 mAh cm −2 . Moreover, full-cell Li-ion battery is constructed by using ­LiFePO 4 and protected Li as a cathode and anode, respectively, rendering a stable capacity after 400 charge/discharge cycles. The current work presents a promising approach to stabilize Li metal anodes for next-generation Li secondary batteries.

Solidification Structure Evolution and Grain Refinement Mechanism of a Deeply Undercooled Ni65Cu35 Alloy

Xiaolong Xu,Yukang An,Hua Hou,Yuhong Zhao 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.2

The maximum 320 K undercooling of Ni65Cu35 alloy was obtained by means of cyclic superheating in the state of moltenglass. The solidification structuresat different undercoolings were systematically studied. There are two grain refinementsatlow and high undercoolings. It was generally believed that the grain refinement atlowundercooling was caused by dendritesuperheat remelting. Electron backscattering diffraction was used to characterize the solidification structure athighundercooling,and obvious random orientation, high-angle grain boundaries and twin boundaries were found, indicating grainrefinement was caused by recrystallization under highundercooling. There were almost no visible dislocation defects in theTEM bright-field images at high undercooling, and the microstructure hardness decreased obviously after grain refinement. This further illustrated the rapid accumulation of stress and defects in recalescenceare completely abreacted in recrystallizationduring post-recalescence period, at the same time as the driving force to promote the second grain refinement inthe microstructure.

Mercury Ions Mediated Phosphorus Containing Carbon Dots as Fluorescent Probe for Biothiols Screening

Han Du,Hu Xu,Yun Zhao,Dan Li,Yuhong Wang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.10

In this study, we report the mercury ions (Hg2+) mediated phosphorus-containing carbon dots (PCDs) as a selective "off–on" fluorescence probe for glutathione (GSH), cysteine (Cys) and homocysteine (Hcys). PCDs obtained by hydrothermal reaction are sensitive to Hg2+ ions and its fluorescence can be significantly quenched owing to the electron transfer from the lowest unoccupied molecular orbital (LUMO) of PCDs to Hg2+. Interestingly, the weak fluorescence of Hg2+-mediated PCDs could be gradually recovered with the addition of GSH, Cys and Hcys. This can be attributed to the formation of Hg2+–S complex due to the super affinity of Hg2+–sulfydryl bond. The formation of Hg2+–S complex extremely reduces the oxidation ability of Hg2+ that inhibits the electron transfer from LUMO of PCDs to Hg2+ and re-opens the native electron transition from LUMO to the highest occupied molecular orbital (HOMO) of PCDs. Thus, the green fluorescence of PCDs is switched on. Furthermore, the present Hg2+-mediated PCDs assay exhibits a high selectivity for GSH, Cys and Hcy and has been successfully used to detect the total biothiols content in human urine samples.