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Research of compound Nd:YAG phase-conjugate resonator with stimulated Brillouin scattering (SBS) cell
Jun Qu,Weijun Zhang,Xiaoming Gao
Optica Applicata , 2005,
Abstract: How to improve the quality of output beam of phase conjugation cavity is a problem. In this paper, the output characteristic of compound phase-conjugate resonator with stimulated Brillouin scattering (SBS) cell was reported. The experimental results indicated it has high output energy and excellent stability. The output energy of the single pulse can reach 90 mJ, and the width of it is about 25 ns. The results of pulse widths, output energies and beam profiles were given.
An Overview on Piezoelectric Power Generation System for Electricity Generation  [PDF]
Xiaoming Sun
Journal of Power and Energy Engineering (JPEE) , 2017, DOI: 10.4236/jpee.2017.52002
Abstract: Coal, petroleum and natural gas will still be the basis of economic development for a long time. However, with a rapider consumption speed, these fossil fuels will be exhausted in the near future. In addition, the usage of these fossil fuels can also cause environmental pollution and greenhouse effect. To deal with energy security and environmental crisis, it is wise to work towards three directions: energy saving and emission reduction, energy recovery, exploration of new renewable energy. Currently, the electricity generation technology using piezoelectric material to recover the compressional or vibrational energy begins to draw attention. However, most of the researches are devoted to designing small self-powered devices. This paper presents an overview of the feasibility of piezoelectric power generation system for electric power system, in which the fundamentals of piezoelectric power generation and the feasible structure of the system are discussed.
Adaptive Quasi-PID Control Method for Switching Power Amplifiers  [PDF]
Xiaoming Sun
Journal of Power and Energy Engineering (JPEE) , 2017, DOI: 10.4236/jpee.2017.52003
Abstract: Quasi-PID control method that is able to effectively inhibit the inherent tracking error of PI control method is proposed on the basis of a rounded theoretical analysis of a model of switching power amplifiers (SPAs). To avoid the harmful impacts of the circuit parameter variations and the random disturbances on quasi-PID control method, a single neuron is introduced to endow it with self-adaptability. Quasi-PID control method and the single neuron combine with each other perfectly, and their formation is named as single-neuron adaptive quasi-PID control method. Simulation and experimental results show that single-neuron adaptive quasi-PID control method can accurately track both the predictable and the unpredictable waveforms. Quantitative analysis demonstrates that the accuracy of single-neuron adaptive quasi-PID control method is comparable to that of linear power amplifiers (LPAs) and so can fulfill the requirements of some high-accuracy applications, such as protective relay test. Such accuracy is very difficult to be achieved by many modern control methods for converter controls. Compared with other modern control methods, the programming realization of single-neuron adaptive quasi-PID control method is more suitable for real-time applications and realization on low-end microprocessors for its simple structure and lower computational complexity.
Analysis on Sensitivity of Power System Stability to Generator Parameters  [PDF]
Xiaoming Sun
Journal of Power and Energy Engineering (JPEE) , 2019, DOI: 10.4236/jpee.2019.71009
Abstract: The sensitivity of power system stability (including transient and dynamic stabilities) to generator parameters (including parameters of generator model, excitation system and power system stabilizer) is analyzed in depth by simulations. From the tables and plots of the resultant simulated data, a number of useful rules are revealed. These rules can be directly applied to the engineering checking of generator parameters. Because the complex theoretical analyses are circumvented, the checking procedure is greatly simplified, remarkably promoting the working efficiency of electrical engineers on site.
Fault Waveform Regenerator and Its Digital Closed-Loop Modification Technique  [PDF]
Xiaoming Sun
Journal of Power and Energy Engineering (JPEE) , 2019, DOI: 10.4236/jpee.2019.72002
Abstract: In order to provide a novel and more effective alternative to the commonly used relay protection testing device that outputs only the sinusoidal testing signals, the concept of fault waveform regenerator is proposed in this paper, together with its hardware structure and software flow chart. Fault waveform regenerator mainly depends on its power amplifiers (PAs) to regenerate the fault waveforms recorded by digital fault recorder (DFR). To counteract the PA’s inherent nonlinear distortions, a digital closed-loop modification technique that is different from the predistortion technique is conceived. And the experimental results verify the effectiveness of the fault waveform regenerator based on the digital closed-loop modification technique.
Re-Os dating of auriferous pyrite from the Zhenyuan super-large gold deposit in Ailaoshan gold belt, Yunnan Province, Southwestern China
GuiYong Shi,XiaoMing Sun,WeiJian Pan,BeiMing Hu,WenJun Qu,AnDao Du,Chao Li
Chinese Science Bulletin , 2012, DOI: 10.1007/s11434-012-5275-z
Abstract: Zhenyuan gold deposit is the largest super large gold deposit in the Ailaoshan gold belt, but its precise mineralization age is still lack. Re-Os isotopic age of the auriferous pyrite from the Zhenyuan gold deposit was determined by using a high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). The pyrite samples were decomposed in carius tubes, Os was separated by distillation and Re was extracted by acetone, respectively. The results show that the Re-Os isochron age is 229±38 Ma (MSWD=2.0, confidence level is 95%), with an initial 187Os/188Os value of 0.68±0.24 and a corresponding γOs value of 442±91. The Re/Os ratios of the pyrite vary from 40.8 to 100.5. The data suggest that at least one important ore-forming event was occurred during Indosinian epoch, and the ore-forming materials probably derived from mixed sources of crustal and mantle, while the later dominated. The Ailaoshan composite orogen experienced complicated evolutional processes, including formation of Precambrian-Early Paleozoic basement, subduction and orogenesis of Late Paleozoic era, collisional orogenesis of Late Hercynian-Indosinain epoch, and extensional or striking orogenesis of Yanshainan-Cenozoic epoch. The polycycle tectonic evolution and magmatism in this area caused multi-stage and superposition metallization characteristics of the Zhenyuan gold deposit: the mineralization probably occur mainly during the Indosinian collisional orogeny, while the minor gold ores of altered granite-porphyry and altered lamprophyre may be formed in the late superposition metallization.
Pten Regulates Development and Lactation in the Mammary Glands of Dairy Cows
Zhuoran Wang, Xiaoming Hou, Bo Qu, Jie Wang, Xuejun Gao, Qingzhang Li
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0102118
Abstract: Pten is a tumor suppressor gene regulating many cellular processes, including growth, adhesion, and apoptosis. In the aim of investigating the role of Pten during mammary gland development and lactation of dairy cows, we analyzed Pten expression levels in the mammary glands of dairy cows by using western blotting, immunohistochemistry, and quantitative polymerase chain reaction (qPCR) assays. Dairy cow mammary epithelial cells (DCMECs) were used to study the function of Pten in vitro. We determined concentrations of β-casein, triglyceride, and lactose in the culture medium following Pten overexpression and siRNA inhibition. To determine whether Pten affected DCMEC viability and proliferation, cells were analyzed by CASY-TT and flow cytometry. Genes involved in lactation-related signaling pathways were detected. Pten expression was also assessed by adding prolactin and glucose to cell cultures. When Pten was overexpressed, proliferation of DCMECs and concentrations for β-casein, triglyceride, and lactose were significantly decreased. Overexpression of Pten down-regulated expression of MAPK, CYCLIN D1, AKT, MTOR, S6K1, STAT5, SREBP1, PPARγ, PRLR, and GLUT1, but up-regulated 4EBP1 in DCMECs. The Pten siRNA inhibition experiments revealed results that opposed those from the gene overexpression experiments. Introduction of prolactin (PRL) increased secretion of β-casein, triglyceride, and lactose, but decreased Pten expression levels. Introduction of glucose also increased β-casein and triglyceride concentrations, but did not significantly alter Pten expression levels. The Pten mRNA and protein expression levels were decreased 0.3- and 0.4-fold in mammary glands of lactating cows producing high quality milk (milk protein >3.0%, milk fat >3.5%), compared with those cows producing low quality milk (milk protein <3.0%, milk fat <3.5%). In conclusion, Pten functions as an inhibitor during mammary gland development and lactation in dairy cows. It can down-regulate DCMECs secretion of β-casein, triglyceride, and lactose, and plays a critical role in lactation related signaling pathways.
Inhibition of dynamin-related protein 1 protects against myocardial ischemia–reperfusion injury in diabetic mice
Cong Huo,Feng Fu,Mingge Ding,Qianqian Dong,Xiaoming Wang,Xin Jia,Xing Li,Yinxian Qu,Zheng Liu,Zhenghua Liu
- , 2017, DOI: 10.1186/s12933-017-0501-2
Abstract: Many cardioprotective pharmacological agents failed to exert their protective effects in diabetic hearts subjected to myocardial ischemia/reperfusion (MI/R). Identify the molecular basis linking diabetes with MI/R injury is scientifically important and may provide effective therapeutic approaches. Dynamin-related protein 1 (Drp1)-mediated mitochondrial fission plays an important role in MI/R injury under non-diabetic conditions. Importantly, recent studies indicated that Drp1-mediated mitochondrial fission is enhanced in the myocardium of diabetic mice. The above evidences suggested that Drp1 may be one critical molecule linking diabetes with MI/R injury. We hypothesized that inhibition of Drp1 may be effective to reduce MI/R injury in diabetic hearts
Erratum to: Inhibition of dynamin-related protein 1 protects against myocardial ischemia–reperfusion injury in diabetic mice
Cong Huo,Feng Fu,Mingge Ding,Qianqian Dong,Xiaoming Wang,Xin Jia,Xing Li,Yinxian Qu,Zheng Liu,Zhenhua Liu
- , 2017, DOI: 10.1186/s12933-017-0540-8
Abstract: After publication of the original article [1], it came to the authors’ attention that Zhenhua Liu’s name had been spelled incorrectly in the author list. The author list is correct in this erratum
Role of Character Strengths and Stress in Psychological Symptoms among Chinese Secondary Vocational School Students  [PDF]
Tingting Li, Xiaoming Liu
Psychology (PSYCH) , 2016, DOI: 10.4236/psych.2016.71007
Abstract: Background: Character strengths are important psychology resources, which affect the academic and social development of students at secondary vocational schools. Purpose: We aimed to clarify the relationship between character strengths, psychological stress, and psychological symptoms among these students from a positive psychological perspective. By focusing on virtues and strengths, we suggest improvements to school education and family upbringing. Sample: A total of 282 secondary vocational school students were recruited. Design and Method: Students were asked to complete the Chinese Virtues Questionnaire, Life Stress Rating Scale, and Symptom Checklist-90. Statistical analyses were conducted using SPSS 19.0. Results: Regression analyses indicated that the interaction between relationship strengths and family stress explained 45% of the variance in psychological symptoms. This study clarified the positive role of character strengths in stressful situations. Thus, helping secondary vocational school students recognize and use their strengths is conducive to improving their health. Conclusion: Our results should also help teachers and parents adopt a strengths perspective, which might encourage students to explore and develop their strengths.
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