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Nuclear Science and Techniques 2020年第8期31卷 43-52页

作者： Sheng Lai Xiao-Bin Tang Jun-Xu Mu Zhao-peng Feng yun-peng liu Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Nuclear Technology Application and Radiation Protection in Astronautics Ministry of Industry and Information TechnologyNanjing 210016China

Stealth technology plays an important role in modern military conflicts, especially when used in fighter jets. Since airfoil structures have a leading edge, inlet, and surface bulge that are easily detected by radar, it is necessary to study the stealth of these structures. In this study,we investigate structures coated with radionuclides to generate plasma. Using simulation and calculation methods, the attenuation of 0.1–10 GHz electromagnetic waves propagating in plasma was studied. The results showed that the attenuation of low-frequency electromagnetic waves is greater than that of high-frequency electromagnetic *** attenuation of 0.1–1 GHz electromagnetic waves is found to be less than-2.7 d B,-3.0 d B, and-15.6 d B at the airfoil leading edge, inlet, and surface bulge structures, respectively. We also found that the attenuation of electromagnetic waves with 0°-incidence is greater than that of waves with 10°, 20°, and 30° incidence ***, the attenuation of electromagnetic waves decreases gradually as the incident angle increases.

关键词： Plasma stealth Radionuclide coating Electromagnetic waves Numerical simulation

Homing Guidance Law with Falling Angle and Flying Time Control

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Journal of Harbin Institute of Technology(New Series) 2014年第1期21卷 55-61页

作者： peng-yun liu Rui-Sheng Sun Wei-Ming Li School of Energy and Power Engineering Nanjing University of Science and Technology

In this paper,a new homing guidance method is used to control the flying time and falling angle for guided missiles. Through this approach,it finds the approximate solution to the quadratic equation of time-togo,which is used for the formula derivation of the flying time control command. In this guidance law design,the acceleration rate control command is adopted. The guidance law is composed of a PN guidance command and a flying time control command. Firstly,it obtains a desired falling angle with accurate guidance. Secondly,it introduces to satisfy the constraint of flying time. The flying time control requires an assumption on the future evolution of missile,which is called time-to-go. To cope with the time-varying speed of missiles,a method of compensating the estimation of time-to-go is presented. The new guidance law is evaluated by using a simulation of typical terminal guidance for rocket-propelled torpedo. The simulation results show that the guidance achieves excellent control performance and exhibits insensitivity to initial trajectory parameter over a widen flight envelope.

关键词： homing guidance law falling angle flying time rocket-propelled torpedo time-to-go

Correlativity between coal permeability and strain in quasi-plane strain state

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 493-499页

作者： Bao-Bin GAO yun-peng liu Stage Key Laboratory Cultivation Base for Gas Geology and Gas Control (Henan Polytechnic University) Jiaozuo 454000 China Opening Project of Key Laboratory of Deep Mine Construction Henan Polytechnic University Jiaozuo 454000 China School of Safety Science and Engineering Henan Polytechnic University Jiaozuo 454000 China

To simulate the variety of big coal sample permeability during the rupture process under quasi-plane strain state, a series of experiments have been performed by a set of self-made coal-gas coupling test system. The test results indicate that the development trend between the permeability rate-strain curve and the stress-strain curve of big coal sample is almost consistent. The permeability rate-strain curve is general hysteretic to stress-strain curve, indicating the close relativity between the evolvement of damage and the development of permeability rate. However, there is time interval between them and the perme- ability rate peaks value when the sample reaches the softened stage after the peak stress. Based on the characteristics of per- meability rate-strain curve, three stages were plotted out： the stage before minimum permeability rate （/co）, the stage between minimum and maximum of permeability rate and the stage after the maximum permeability rate （kmax）. According to the three stages of permeability rate, the segmental curve equations of permeability rate-strain were fitted： the first stage can be fitted with negative exponential function; the second stage can be fitted with Boltzmann equation; and the last stage can be fitted with multinomial equation.

关键词： permeability quasi-plane strain coal-gas coupling test system stress-strain

Adaptive Sliding Mode BTT Autopilot for Cruise Missiles with Variable-Swept Wings

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Journal of Harbin Institute of Technology(New Series) 2014年第2期21卷 33-42页

作者： Wei-Ming Li Rui-Sheng Sun Hong-Yang Bai peng-yun liu School of Energy and Power Engineering Nanjing University of Science and Technology

In this paper,an adaptive sliding mode method was proposed for BTT autopilot of cruise missiles with variable-swept wings. To realize the whole state feedback,the roll angle,normal overloads and angular rates were considered as state variables of the autopilot,and a parametric sliding mode controller was designed via feedback linearization. A novel parametric adaptation law was put forward to estimate the nonlinear timevarying parameter perturbations in real time based on Lyapunov stability theory. A sliding mode boundary layer theory was adopted to smooth the discontinuity of control variables and eliminate the control chattering. The simulation was presented for the roll angle and overload commands tracking in different configuration schemes. The results indicated that the controlled system has robust dynamic tracking performance in condition of the large-scale aerodynamic parametric variety resulted from variable-swept wings.

关键词： BTT autopilot adaptive sliding mode control variable-sweep wing

LEUKOCYTOSIS AND RETINOIC ACID SYNDROME IN PATIENTS WITH ACUTE PROMYELOCYTIC LEUKEMIA TREATED WITH ARSENIC TRIOXIDE

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Chinese Medical Sciences Journal 2006年第3期21卷 171-174页

作者： Bo Jin Ke-zuo Hou yun-peng liu Ping Yu Department of Medical Oncology the First Affiliated Hospital China Medical University Shenyang 110001

Objective To study the incidence of leukocytosis and retinoic acid （RA） syndrome in newly diagnosed and relapsed acute promyelocytic leukemia （APL） patients treated with arsenic trioxide （ATO）. Methods Thirty patients with newly diagnosed or relapsed APL received ATO for remission induction at the dose of 10 mg/d. RA syndrome was defined when patient was with one or more of the following signs or symptoms： fever, dyspnea, serous cavity effusion, muscular pain, pulmonary infiltration, weight gain, or pulmonary infiltration on chest X-ray. Results Twenty-three （77%） patients achieved complete remission, mean time to remission was 37. 1 days. Leukocytosis was observed in 14 （47%） patients, mean time to leukocytosis was 12. 7 days, median baseline leukocyte count for patients with leukocytosis was 3.1 x 109/L, which was higher than that for patients who did not de,.＇elop leukocytosis （2.6 × 10^9/L, z = - 2. 635, P = 0. 008）. No other cytotoxic therapy was administered, and the leukocytosis resolved in all cases. The RA syndrome was observed in 9 （30%） patients, mean time to diagnose of RA syndrome was 13.9 days, median baseline leukocyte count for patients with RA syndrome was 3.6 × 10^9/L, which was higher than that for patients who did not develop RA syndrome （2. 6 × 10^9/L, z = - 1. 909, P =0. 046）. No patient died of RA syndrome. Conclusion Leukocytosis and RA syndrome are associated with ATO and baseline leukocyte count respectively, and there is distinct link between leukocytosis and RA syndrome.

关键词： arsenic trioxide acute promyelocytic leukemia leukocytosis retinoic acid syndrome

Dependence of Performance of Organic Light-emitting Devices on Sheet Resistance of Indium-tin-oxide Anodes

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Chemical Research in Chinese Universities 2006年第4期22卷 427-431页

作者： ZHOU Liang ZHANG Hong-jie YU Jiang-bo MENG Qing-guo peng Chun-yun liu Feng-yi DENG Rui-ping peng Ze-ping LI Zhe-feng Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

The dependence of the performance of organic light-emitting devices（OLEDs） on the sheet resistance of indiumtin-oxide（ITO） anodes was investigated by measuring the steady state current density brightness voltage characteristics and the electroluminescent spectra. The device with a higher sheet resistance anode shows a lower current density, a lower brightness level, and a higher operation voltage. The electroluminescence（EL） efficiencies of the devices with the same structure but different ITO anodes show more complicated differences. Furthermore, the shift of the light-emitting zone toward the anode was found when an anode with a higher sheet resistance was used. These performance differences are discussed and attributed to the reduction of hole injection and the increase in voltage drop over ITO anode with the increase in sheet resistance.

关键词： Organic light-emitting device(OLED) Indium-tin-oxide(ITO) Sheet resistance Balance of holes and electrons

Correction of distorted X-ray absorption spectra collected with capillary sample cell

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Nuclear Science and Techniques 2023年第7期34卷 179-188页

作者： Hao Wang Yue-Cheng Lai Jia-Jun Zhong yun-peng liu Lei Yao Li-Xiong Qian Xue-Qing Xing Zhong-Jun Chen Guang Mo Zhong-Hua Wu Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

In certain exceptional cases,capillary samples must be used to measure X-ray absorption spectra(XAS).However,the inho-mogeneous thickness of capillary samples causes XAS *** study discusses the distortion and correction of the XAS curve caused by the inhomogeneous thickness of capillary *** relationship between the distorted XAS curveμ′d_(eq)(measured values)and the real absorption coefficientμ_(s)d_(eq)(true values)of the sample was *** distortion was slight and negligible when the vertical size(2h)of the X-ray beam spot was smaller than 60%of the capillary tube’s inner diameter(2R_(in)).When h/R_(in)>1,X-ray leakage is inevitable and should be avoided during *** X-ray leakage caused by an X-ray beam spot size larger than the inner diameter of the capillary tube leads to serious compressed distortion of the XAS *** h/R_(in)<1,the distorted XAS data were well *** errors and their influence on the corrected XAS are also *** and corrections for distortions verify the feasibility and effectiveness of the corrected method.

关键词： XAS Capillary Compression distortion Correction Python

Silicon PIN photodiode applied to acquire high-frequency sampling XAFS spectra

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Nuclear Science and Techniques 2022年第7期33卷 15-24页

作者： yun-peng liu Lei Yao Bing-Jie Wang Jia-Jun Zhong Hao Wang Li-Xiong Qian Zhong-Jun Chen Guang Mo Xue-Qing Xing Wei-Fan Sheng Zhong-Hua Wu Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing100049China

Experimental techniques based on SR facilities have emerged with the development of synchrotron radiation(SR)***,detector miniaturization has become significant for the development of SR experimental *** this study,the miniaturization of a detector was achieved by coupling a commercial silicon PIN photodiode(SPPD)into a beamstop,aiming for it not only to acquire X-ray absorption fine structure(XAFS)spectra,but also to protect the subsequent two-dimensional detector from high-brilliance X-ray radiation damage in certain combination *** mini SPPD detector coupled to a beamstop was used as the rear detector in both the conventional sampling scheme and novel high-frequency(HF)sampling scheme to collect the transmission XAFS *** ion chambers were also used to collect the transmission XAFS spectra,which were used as the *** XAFS spectra were quantitatively analyzed and compared;the results demonstrated that the XAFS spectra collected by this SPPD in both the conventional sampling scheme and HF sampling scheme are *** study provides a new detector-selection scheme for the acquisition of the quick-scanning XAFS(QXAFS)and HF sampling XAFS *** SPPD detector presented in this study can partially meet the requirements of detector miniaturization.

关键词： Silicon PIN photodiodes Beamstop XAFS High frequency sampling

Synthesis and Antibacterial Activities of Selenide Derivatives of Benzisoselenazolone

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Wuhan University Journal of Natural Sciences 2001年第4期6卷 851-853页

作者： Yang Li ping, Wu jun, peng yun shan, liu Xiu fang, Xu Han sheng College of Chemistry and Molecular, Wuhan University, Wuhan 430072, China Wuhan University College of Chemistry and Molecular Wuhan China (GRID:grid.49470.3e) (ISNI:***)

A series of Benzisolselenazolone (BISA) derivatives were synthesized and evaluated for their antibacterial activities againstE coli. by using LKB-2277 bioactivity monitor. Other bioactivities were tested by the method of High Throughput Screening for pharmaceutical activity compounds (HTP) BISA derivatives 3b, at the concentration of 40 μg/mL, showed 100%antibacterial activity and 62%inhibition rate of aldose reductase (at the concentration of 5μg/mL). These new compound structures have determined by IR,1H NMR and MS spectra.

关键词： BISA Ebselen antibacterial activity NO synthase Aldose reductase

Risk factors for lymph node metastasis and evaluation of reasonable surgery for early gastric cancer

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World Journal of Gastroenterology 2007年第38期13卷 5133-5138页

作者： Ying-Ying Xu Bao-Jun Huang Zhe Sun Chong Lu yun-peng liu Department of Medical Oncology First Hospital of China Medical University Shenyang 110001 Liaoning Province China Department of Surgical Oncology First Hospital of China Medical University Shenyang 110001 Liaoning Province China

AIM: To give the evidence for rationalizing surgical therapy for early gastric cancer with different lymph node status. METHODS: A series of 322 early gastric cancer patients who underwent gastrectomy with more than 15 lymph nodes retrieved were reviewed in this study. The rate of lymph node metastasis was calculated. Univariate and multivariate analyses were performed to evaluate the independent factors for predicting lymph node metastasis. RESULTS: No metastasis was detected in No.5, 6 lymph nodes (LN) during proximal gastric cancer total gastrectomy, and in No.10, 11p, 11d during for combined resection of spleen and splenic artery and in No.15 LN during combined resection of transverse colon mesentery. No.11p, 12a, 14v LN were proved negative for metastasis. The global metastastic rate was 14.6% for LN, 5.9% for mucosa, and 22.4% for submucosa carcinoma, respectively. The metastasis in group Ⅱ?was almost limited in No.7, 8a LN. Multivariate analysis identified that the depth of invasion, histological type and lymphatic invasion were independent risk factors for LN metastasis. No metastasis from distal cancer (≤ 1.0 cm in diameter) was detected in group Ⅱ?LN. The metastasis rate increased significantly when the diameter exceeded 3.0 cm. All tumors (≤ 1.0 cm in diameter) with LN metastasis and mucosa invasion showed a depressed macroscopic type, and all protruded carcinomas were > 3.0 cm in diameter. CONCLUSION: Segmental/subtotal gastrectomy plus D1/D1 + No.7 should be performed for carcinoma (≤ 1.0 cm in diameter, protruded type and mucosa invasion).Subtotal gastrectomy plus D2 or D1 + No.7, 8a, 9 is the most rational operation, whereas No.11p, 12a, 14v lymphadenectomy should not be recommended routinely for poorly differentiated and depressed type of submucosa carcinoma (> 3.0 cm in diameter). Total gastrectomy should not be performed in proximal, so does combined resection or D2+/D3 lymphadenectomy.

关键词： Lymph node Metastasis Surgery Early gastric cancer