Carbon-Ion-Implanted Nd, MgO-Codoped Near-Stoichiometric Lithium-Niobate Optical Waveguides

Ning-Ning Dong,Yang Tan,Yan-Xia Kong,Feng Chen,Hong-Ji Ma 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.6

Nd, MgO codoped near stoichiometric lithium niobate (Nd:MgO:SLN) is a promising laser gain crystal for infrared laser generations. We report on, to our knowledge for the first time, the planar waveguide formation in Nd:MgO:SLN crystal by MeV carbon ion implantation at dose of 1014 ions/cm2. The guiding properties are investigated by using the well-known m-line technique and end-face arrangement. The refractive index profiles of the waveguides show a typical “well + barrier” distribution, which could confine the light propagation in a non-leaky way. In addition, a numerical simulation of the light propagation shows that the waveguide modal distributions are in good agreement with the experimental data, which means potential applications for the formation of designable devices in Nd:MgO:SLN by using carbon ion implantation. Nd, MgO codoped near stoichiometric lithium niobate (Nd:MgO:SLN) is a promising laser gain crystal for infrared laser generations. We report on, to our knowledge for the first time, the planar waveguide formation in Nd:MgO:SLN crystal by MeV carbon ion implantation at dose of 1014 ions/cm2. The guiding properties are investigated by using the well-known m-line technique and end-face arrangement. The refractive index profiles of the waveguides show a typical “well + barrier” distribution, which could confine the light propagation in a non-leaky way. In addition, a numerical simulation of the light propagation shows that the waveguide modal distributions are in good agreement with the experimental data, which means potential applications for the formation of designable devices in Nd:MgO:SLN by using carbon ion implantation.

Synthesis and Characterization of KTiNbO5 Nano-particles by Novel Polymerizable Complex Method

Ning-ning Wang,Yun-xiang Lan,Jie He,Rui Dong,Jin-song Hu 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.9

The layered KTiNbO5 was successfully synthesized with titanium(IV) isopropoxide and niobium oxalate by a novel polymerized complex (PC) method. The morphology and structure of the as-prepared sample was characterized by means of High-Resolution Transmission Electron Microscope, powder X-ray diffraction, and Laser Raman Spectroscopy. The spectral response characteristic was recorded by using UV-vis Diffuse Reflectance Spectroscopy. Results show that KTiNbO5 as-prepared by PC method presents an uniform morphology of nano-particles, the mean particle sizes is ca. 28 nm corresponding to the (002), and the crystal structure can be well indexed to the orthorhombic phase. The sample as-prepared by PC method has higher band gap energy than that of the sample prepared by a solid-state reaction method due to the quantum size effect.

Identifying a Cinnamoyl Coenzyme A Reductase (CCR) Activity with 4-Coumaric Acid: Coenzyme A Ligase (4CL) Reaction Products in Populus tomentosa

Dong-Dong Wang,Hua Bai,Wei-Qi Chen,Hai Lu,Xiang-Ning Jiang 한국식물학회 2009 Journal of Plant Biology Vol.52 No.5

A cinnamoyl coenzyme A reductase (CCR, EC 1.2.1.44), one of the key enzyme involved in lignin biosynthesis, was cloned from Populus tomentosa (Chinese white poplar). At the same time, a 4CL1 gene was cloned from P. tomentosa, too. The two genes were subcloned in pQE31 vector and expressed in Escherichia coli M15. Both of them were purified by Ni-NTA. Purified CCR protein was digested by trypsin and analyzed by HPLC-MS; the peptide segments had 27% similarity with the sequence of the CCR protein. 4CL was thought to be a neighbor enzyme of CCR in lignin biosynthesis. In this paper, a 4CL1 from P. tomentosa was cloned, and its enzyme reaction products were extracted for the substrates of CCR. Three 4CL1 enzyme reaction products were monitored by HPLC-MS and then the CCR enzyme reaction was detected by GC-MS. In the CCR reaction, the three corresponding aldehyde (p-coumaraldehyde, caffealdehyde, and coniferaldehyde) were detected and identified by Frontier3 software. The results showed that the CCR that we cloned from P. tomentosa had affinities with 4CL1 enzyme reaction products and a ptCCR that was cloned from aspen (Li et al., Plant Cell Physiol 46(7):1073–1082, 2005) only had affinity with feruloyl-CoA. The different results maybe depend on the different study method. The method of exacting 4CL enzyme products as the substrates of CCR in the paper was reliable and can be used in lignin biosynthesis network to detect the enzymes in the neighborhood that depended on the polarity of the substrates and products. This CCR gene had eight homology sequence CCR gene when a BLAST was conducted in Populus trichocarpa genome database. The CCR homology genes in Populus suggested that some CCRs may take part in the lignin biosynthesis, too. The gene family would be the hot spot in the future study.

Endostar Combined with Cisplatin Inhibits Tumor Growth and Lymphatic Metastasis of Lewis Lung Carcinoma Xenografts in Mice

Dong, Xiao-Peng,Xiao, Tian-Hui,Dong, Hong,Jiang, Ning,Zhao, Xiao-Gang Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.5

Objective: To investigate the effects of endostar, a recombined humanized endostatin, plus cisplatin on the growth, lymphangiogenesis and lymphatic metastasis of the Lewis lung carcinoma (LLC) in mice. Methods: A tumor model were established in C57BL/6 mice by intravenious transplantation of LLC cells. Then the mice were randomized to receive administration with NS, endostar, cisplatin, or endostar plus cisplatin. After the mice were sacrificed, tumor multiplicity, tumor size and lymph node metastasis were assessed. Then the expression of vascular endothelial growth factor-c (VEGF-C) and podoplanin were determined by immunohistochemical staining. Results: Endostar plus cisplatin significantly suppressed tumor growth. lymphatic metastasis and prolonged survival time of the mice without obvious toxicity. The inhibition of lymphatic metastasis was associated with decreased microlymphatic vessel density (MLVD) and expression of VEGF-C. Conclusions: Endostar combined with cisplatin was more effective to suppress tumor growth and lymphatic metastasis than either agent alone. Thus this may provide a rational alternative for lung carcinoma treatment.

Wear Mechanism Analysis and Its Effects on the Cutting Performance of PCBN Inserts during Turning of Hardened 42CrMo

Ning Li,Yong-Jie Chen,Dong-Dong Kong 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.9

Super-strength steel 42CrMo after quenched and tempered has been widely applied to crucial parts due to the properties such as good impact toughness and high fatigue limit. However, it falls into the category of most difficult-to-cut material because of its high cutting resistance and low thermal conductivity, which can easily lead to tool breakage. To increase efficiency, ensure quality and reduce costs, wear modes and its corresponding mechanism of PCBN inserts were experimentally investigated during turning of the hardened 42CrMo (62-65 HRC) in this paper. The results suggest brittle fracture is the main failure mode. The wear mechanism was mainly abrasive wear and adhesion/diffusion wear, accompanying oxidation wear and chipping. Within the cutting range studied in this work, the operation for turning instead of grinding can be realized and the optimal cutting speed range is 140-170 m/min. The static forces fluctuate with tool wear, while other performance indexes such as maximum cutting forces, impact forces, cutting power, specific cutting energy, and coefficient of friction at the tool-chip interface all show a rising trend with tool wear, which can be extracted as features. The research results obtained in this paper will provide guidelines for the industrial production and tool wear real-time monitoring.

Study on the coupling relationship between wear and dynamics under steady uniform temperature field of planetary gear system

Ning Dong,Jianxing Zhou,Ruiting Tong,Quanwei Cui,Yiyi Kong,Junshang Feng,Shichen Xiao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.12

Wear of tooth profiles and thermal deformation caused by temperature changes are difficult to avoid in gear systems and have important effects on the performance, even to failure. In this paper, a dynamic wear prediction model with coupled thermal deformation and wear is proposed to study the interaction between wear and dynamics of planetary gear system under temperature field, accounting for the effect of temperature on material properties. The system's performance under different wear cycles and temperatures is analyzed. The results show that the difference in the structure makes the curve shape of the thermal deformation error for the external and internal gear pairs completely different, which in turn affects the dynamic response. The distribution and the degree of fluctuation of tooth profile wear depth change as the mesh cycle increases. The early wear is beneficial to the system's uniform load performance and vibration, and the performance decreases as the wear increases, but the external and internal gear pairs are affected by wear to a different extent. The thermal deformation and wear errors have competing or facilitating mechanisms depending on the temperature difference and the degree of wear.

Study on wear evolution of spur gears considering dynamic meshing stiffness

Ning Dong,Quanwei Cui,Jianxing Zhou,Ruiting Tong,Haiwei Wang,Feng-xia Lu 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.7

Wear is an inevitable phenomenon in gear systems and has a great impact on performance and longevity. In view of the fact that the actual variation of meshing stiffness in the double teeth contact region and the nonlinear relationship between meshing stiffness and force are ignored in previous wear prediction studies, a new method with loss-of-lubrication is proposed in this study. A translational-torsional dynamic model is developed for the coupling effect between wear and dynamic characteristics of external spur gears. To obtain more precise dynamic responses, the meshing stiffness and force are coupled with tooth wear, taking into account the structural coupling effect and nonlinear contact. The tooth surface is then discretized, and a wear model is developed based on Archard wear equation, in which the average pressure is used for the engaging point. Experiments and numerical simulations are carried out to analyze the wear pattern and the interaction between wear and dynamic responses. The results show that the progressive wear process is self-adaptive. Meanwhile, the area with the largest wear depth moves slightly from the dedendum and addendum to the pitch line as the wear cycle increases. When the wear depth is at the level of the tooth profile deviation, the influence of wear on meshing stiffness is very small within the single tooth contact region. However, there is a significant decrease in the stiffness of the double teeth contact, and this decrease is related to the wear cycle and torque. At the initial wear phase, as the load increases, the fluctuation of the wear depth within the engaging-in region intensifies and the overall wear depth increases. With the increment of rotate speed, the engaging-in impact makes the fluctuant area of wear depth become larger.

Effect of cell-penetrating peptide-conjugated estrogen-related receptor ${\beta}$ on the development of mouse embryos cultured in vitro

Yang, Ning Jie,Seol, Dong-Won,Jo, Junghyun,Jang, Hyun Mee,Yoon, Sook-Young,Lee, Dong Ryul The Korean Society for Reproductive Medicine 2014 Clinical and Experimental Reproductive Medicine Vol.41 No.1

Objective: Estrogen related receptor ${\beta}$ (Esrrb) is a member of the orphan nuclear receptors and may regulate the expression of pluripotencyrelated genes, such as Oct4 and Nanog. Therefore, in the present study, we have developed a method for delivering exogenous ESRRB recombinant protein into embryos by using cell-penetrating peptide (CPP) conjugation and have analyzed their effect on embryonic development. Methods: Mouse oocytes and embryos were obtained from superovulated mice. The expression of Oct4 mRNA and the cell number of inner cell mass (ICM) in the in vitro-derived and in vivo-derived blastocysts were first analyzed by real time-reverse transcription-polymerase chain reaction and differential staining. Then 8-cell embryos were cultured in KSOM media with or without $2{\mu}g/mL$ CPP-ESRRB protein for 24 to 48 hours, followed by checking their integration into embryos during in vitro culture by Western blot and immunocytochemistry. Results: Expression of Oct4 and the cell number of ICM were lower in the in vitro-derived blastocysts than in the in vivo-derived ones (p<0.05). In the blastocysts derived from the CPP-ESRRB-treated group, expression of Oct4 was greater than in the non-treated groups (p<0.05). Although no difference in embryonic development was observed between the treated and non-treated groups, the cell number of ICM was greater in the CPP-ESRRB-treated group. Conclusion: Treatment of CPP-ESRRB during cultivation could increase embryos' expression of Oct4 and the formation rate of the ICM in the blastocyst. Additionally, an exogenous delivery system of CPP-conjugated protein would be a useful tool for improving embryo culture systems.

Supplementation With Cell-Penetrating Peptide-Conjugated Estrogen-Related Receptor β Improves the Formation of the Inner Cell Mass and the Development of Vitrified/Warmed Mouse Embryos

Yang, Ning Jie,Seol, Dong-Won,Jo, Junghyun,Jang, Hyun Mee,Yoon, Sook-Young,Lee, Woo Sik,Lee, Dong Ryul Springer-Verlag 2016 Reproductive sciences Vol.23 No.11

Synthesis and Characterization of KTiNbO₅ Nano-particles by Novel Polymerizable Complex Method

Wang, Ning-Ning,Lan, Yun-Xiang,He, Jie,Dong, Rui,Hu, Jin-Song Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.9

The layered $KTiNbO_5$ was successfully synthesized with titanium(IV) isopropoxide and niobium oxalate by a novel polymerized complex (PC) method. The morphology and structure of the as-prepared sample was characterized by means of High-Resolution Transmission Electron Microscope, powder X-ray diffraction, and Laser Raman Spectroscopy. The spectral response characteristic was recorded by using UV-vis Diffuse Reflectance Spectroscopy. Results show that $KTiNbO_5$ as-prepared by PC method presents an uniform morphology of nano-particles, the mean particle sizes is ca. 28 nm corresponding to the (002), and the crystal structure can be well indexed to the orthorhombic phase. The sample as-prepared by PC method has higher band gap energy than that of the sample prepared by a solid-state reaction method due to the quantum size effect.