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Optimization of listening time of S-MAC for wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 41-45,70页

作者： li Cheng wang Kui-ru ZHANG Jin-long ZHAO de-xin li wang Key Laboratory of Optical Communications and lightwave Technologies Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In wireless sensor networks, sensor nodes are usually battery-operated computing and sensing devices, hence operations are limited by the initially equipped batteries, which are hard to be recharged or replaced. ：In this sense, saving energy consumption becomes significant. As most energy waste is from the always-on wireless interface, S-MAC is suggested to reduce energy consumption by introducing periodic listen/sleep scheme. However, when designing the listening time, S-MAC fails to consider the traffic distribution factor. In this article, an optimization for this scheme is proposed based on the distribution model. Evaluations show that the optimized S-MAC achieves considerable improvement in energy and latency.

关键词： wireless sensor networks S-MAC traffic distribution energy waste latency

Numerical studies of atomic three-step photoionization processes with non-monochromatic laser fields

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Chinese Physics B 2022年第6期31卷 300-309页

作者： Xiao-Yong Lu li-de wang Yun-Fei li Science and Technology on Particle Transport and Separation Laboratory Tianjin 300180China

The atomic selective multi-step photoionization process is a critical step in laser isotope *** this work,we study three-step photoionization processes with non-monochromatic laser fields theoretically based on the semi-classical ***,three bandwidth models,including the chaotic field model,de-correlation model,and phase diffusion model,are introduced into the density matrix *** numerical results are compared with each other *** phase diffusion model is selected for further simulations in terms of the correspondence degree to physical ***,numerical calculations are carried out to identify the influences of systematic parameters,including laser parameters(Rabi frequency,bandwidth,relative time delay,frequency detuning)and atomic Doppler broadening,on photoionization *** order to determine the optimal match among different systematic parameters,the ionization yield of resonant isotope,and selectivity factor are adopted as evaluation indexes to guide the design and optimization *** results in this work can provide a rewarding reference for laser isotope separation.

关键词： non-monochromatic laser field bandwidth model ionization yield selectivity factor

Rational design of three-dimensional nitrogen and phosphorus co-doped graphene nanoribbons/CNTs composite for the oxygen reduction

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Chinese Chemical Letters 2016年第4期27卷 597-601页

作者： Jie wang Ze-Xing Wu li-li Han Yuan-Yang liu Jun-Po Guo Huolin L.Xin de-li wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education Hubei Key Laboratory of Material Chemistry and Service Failure School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Center for Functional Nanomaterials Brookhaven National Laboratory School of Materials Science and Engineering Tianjin University

In the present work, we report nitrogen and phosphorus co-doped 3-D structured carbon nanotube intercalated graphene nanoribbon composite. The graphene nanoribbons are prepared via partial exfoliation of multi-walled carbon nanotubes. In the graphene nanoribbons/CNTs composite, carbon nanotubes play a role of skeleton and support the exfoliated graphene nanoribbons to form the stereo structure. After high temperature heat-treatment with ammonium dihydrogen phosphate, the unique structure reserves both the properties of carbon nanotube and graphene, exhibiting excellent catalytic performance for the ORR with excellent onset and half-wave potential, which is similar to commercial Pt/C electrocatalysts.

关键词： Graphene nanoribbons Carbon nanotube Doping Electrocatalyst Oxygen reduction reaction

Numerical studies of isotopic selective photoionization of ytterbium in a three-step ionization scheme

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Chinese Physics B 2023年第5期32卷 395-404页

作者：卢肖勇王立德 Science and Technology on Particle Transport and Separation Laboratory CNNCTianjin 300180China

Selective photoionization of ytterbium isotope is studied numerically based on a three-step photoionization scheme,4f^(14)6s^(21)S_0(0 cm^(-1))→4f~(14)6s6p~3P_1(17992.008 cm^(-1))→(4f~(13)6s~26p)(7/2,3/2)_2(35196.98 cm^(-1))→auto-ionization state(52353 cm^(-1))→Yb^(+),by the density matrix theory with the consideration of atomic hyperfine structures and magnetic *** examine the physical model,the numerical isotopic abundance of ytterbium is compared with that from mass spectroscopy experiment,showing that they are in good agreement with each *** excitation process and ionization process of ytterbium,especially for odd isotopes,are discussed and analyzed in detail on this *** effects of frequency detuning,power densities,spectral bandwidths,polarization of two excitation lasers,and atomic Doppler broadening on the total ionization yield and isotopic abundance are investigated numerically and the optimal excitation conditions for~(176)Yb enrichment are identified semi-quantitatively.

关键词： ytterbium isotope hyperfine structure selective photoionization

Passive mode locked diode-pumped Nd:GdYVO_4 laser with a GaAs absorber

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Optoelectronics Letters 2008年第6期4卷 422-424页

作者： DAI Wei li de-chuan wang Ming-jian ZHANG Shuai-yi YU Guo-lei li Jian College of Physics and Electronics Shandong Normal University Jinan 250014 China

A passively Q-switched mode-locked Nd:GdYVO4 laser is successfully demonstrated by using a piece of GaAs crystal grown at low temperature as the passively saturated absorber and the output coupler. Fundamental properties of the Nd: GdYVO4 laser are investigated. The maximum average output power of 3.5 W is obtained by using plainsphere when the incident pumping power is 10 W,which corresponds to an optical-optical coversion efficiency of 35%. The threshold power for the Q-switching mode-locked is 1.2 W. The maximum average output power of 1.72 W is obtained by using GaAs when the incident pumping power is 10 W,mode-locked pulse train with a repetition rate of ～113 MHz is achieved. At the incident laser pumping power of 7 W,the modulation depth is 100%.

关键词：滤波器 GaAs Nd:GdYVO4 激光器

development and Validation of a Nomogram for Predicting the 1-,3-,and 5-year Survival in Patients with Acinar-predominant Lung Adenocarcinoma

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Current Medical Science 2022年第6期42卷 1178-1185页

作者： Zhi-chao ZUO li-de wang Ke PENG Jing YANG Xiong li Zhi ZHONG Huan-ming ZHANG Xin OUYANG Qi XUE department of Radiology Xiangtan Central HospitalXiangtan411000China department of Thoracic Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China department of Spine Surgery the Second Xiangya HospitalCentral South UniversityChangsha410011China department of Plastic Surgery Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyang441000China

Objective This study aimed to develop a nomogram to predict the overall survival(OS)of patients with acinar-predominant adenocarcinoma(APA).Methods Data from patients with APA obtained from the Surveillance,Epidemiology,and End Results(SEER)database between 2008 and 2016 were *** prognostic factors were incorporated to construct a nomogram for predicting the 1-,3-,and 5-year OS in these *** discrimination and calibration abilities of the nomogram were assessed using a C-index and calibration curves,*** A total of 2242 patients with APA were randomly divided into a training cohort(n=1576)and validation cohort(n=666).The independent prognostic factors for OS incorporated into the nomogram included marital status,age,gender,differentiation grade,T stage,N stage,and M *** nomogram showed good prediction capability,as indicated by the C-index[0.713,95%confidence interval(CI):0.705–0.721 in the training cohort,and 0.662,95%CI:0.649–0.775 in the validation cohort].The calibration curves demonstrated that the 1-,3-,and 5-year OS probabilities were consistent between the observed and predicted outcome *** were divided into the high-risk and low-risk groups with the former showing significantly worse survival than the latter(Plished to predict the 1-,3-,and 5-year OS of patients with APA and was superior to the tumor size,lymph node,and metastasis staging system in terms of evaluating long-term prognosis.

关键词： acinar-predominant adenocarcinoma nomogram overall survival prediction model

Triptolide Inhibits Expression of Inflammatory Cytokines and Proliferation of Fibroblast-like Synoviocytes Induced by IL-6/sIL-6R-Mediated JAK2/STAT3 Signaling Pathway

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Current Medical Science 2021年第1期41卷 133-139页

作者： Jian-jing liN Ke TAO Nan GAO Hui ZENG de-li wang Jun YANG Jian WENG National&Local Joint Engineering Research Center of Orthopaedic Biomaterials Department of Bone and Joint SurgeryPeking University Shenzhen HospitalShenzhen518000China Arthritis Clinical and Research Center Peking University People’s HospitalBeijing100044China department of Rheumatism and Immunology Peking University Shenzhen HospitalShenzhen518000China department of Radiology Peking University Shenzhen HospitalShenzhen518000China

Triptolide,a component of the Chinese herb Tripterygium wilfordii Hook F,has been proved to be effective in the treatment of rheumatoid arthritis(RA).However,its underlying mechanisms on RA have not yet been well *** observed the inhibitory effect of triptolide on the expression of inflammatory cytokines and proliferation of fibroblast-like synoviocytes(FLS)induced by the complex of interleukin-6(IL-6)and the soluble form of the IL-6 receptor(sIL-6R).Furthermore,to clarify the underlying mechanisms,we treated FLS with the Janus-activated kinase 2(JAK2)inhibitor/signal transducer and activator of transcription 3(STAT3)activation blocker *** this study,immunohistochemical staining was used to identify vimentin(+)and CD68(−)in *** FLS proliferation was measured by cell proliferation assay,and the cell cycles were analyzed by flow ***,EliSA was used to detect the expression of the inflammatory factors in culture *** expression levels of p-JAK2,JAK2,p-STAT3 and STAT3 were investigated through Western blotting *** results showed that IL-6/sIL-6R significantly increased the cell proliferation and expression of inflammatory cytokines,including IL-6,interleukin-1β(IL-1β)and vascular endothelial growth factor(VEGF).Triptolide or AZD1480 inhibited the cell proliferation and inflammatory cytokine expression in IL-6/sIL-6R-stimulated FLS by suppressing JAK2/*** study suggested that the physiological effects of triptolide on RA were due to its contribution to the inhibition of the inflammatory cytokine expression and FLS proliferation by suppressing the JAK2/STAT3 signaling *** may provide an innovative insight into the effect of triptolide in preventing RA pathogenesis.

关键词： triptolide inflammatory cytokines proliferation fibroblast-like synoviocytes JAK2/STAT3

Effect of cyclic heat treatment on microstructure and mechanical properties of 50CrV4 steel

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Journal of Central South University 2015年第2期22卷 409-415页

作者：李红英韩茂盛李德望李俊徐德超 School of Materials Science and Engineering Central South University Research Institute Baoshan Iron & Steel Co.Ltd.

An annealed 50 Cr V4 steel was subjected to cyclic heat treatment process that consists of repeated short-duration(200 s)held at 840 °C(above Ac3 temperature of 790 °C) and short-duration(100 s) held at 700 °C(below Ac1 temperature of 710 °C). The spheroidization ratio of cementite and the average size of particles increase with increasing the cyclic number of heat treatment. After5-cycle heat treatment, the spheroidization ratio of cementite is 100%, and the average size of the cementite particles is about0.53 μm. After cyclic heat treatment, the hardness, ultimate tensile strength and yield strength of the experimental steel gradually decrease with increasing cyclic number of heat treatment. The elongation of the as-received specimens is about 7.4%, the elongation of the 1-cycle specimen is 14.3%, and the elongation of 5-cycle specimen reaches a peak value of 22.5%, thereafter marginally decreases to 18.3% after 6-cycle heat treatment. Accordingly, the fractured surface initially exhibits the regions of wavy lamellar fracture. By increasing the cyclic number of heat treatment cycles, the regions of dimples consume the entire fractured surface gradually. Some large dimples can be found in the fracture surface of the specimen subjected to six heat treatment cycles.

关键词： cyclic heat treatment accelerated spheroidization mechanical properties

Nitric Oxide Emission Following Wetting of Dry Soils in Subtropical Humid Forests

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Pedosphere 2009年第6期19卷 692-699页

作者： li de-Jun and wang Xin-Ming 2 State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China) [a]State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 (China)

Information about soil nitric oxide （NO） emissions from subtropical forests is quite limited, and even less is known about the pulse emission of NO when wetting soils after a long period of dryness. In this study, we measured NO fluxes following wetting of dry soft in a broadleaf forest and a pine forest in subtropical China. Large pulses of NO fluxes were observed after soil wetting in both forests. NO fluxes increased significantly within 0.5 h following wetting in both forests and reached peak 1 and 4 h after soil wetting in the pine forest and the broadleaf forest, respectively. In the broadleaf forest, averaged peak flux of NO pulses was 157 ng N m^-2 s^-1, which was 8 times the flux value before wetting, and in the pine forest, the averaged peak flux was 135 ng N m-2 s 1, which was 15.5 times the flux value before wetting. The total pulses-induced NO emissions during the dry season were roughly estimated to be 29.4 mg N m^-2 in the broadleaf forest and 22.2 mg N m^-2 in the pine forest or made up a proportion of 4.6% of the annual NO emission in the broadleaf forest and 5.3% in the pine forest.

关键词： dry season flux. NO. pulse subtropical China