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| 1 | Measurement of the echo reduction for underwater acoustic passive materials by using the time reversal technique显示文摘A measuring method of the echo reduction of passive materials by using the time reversal(TR) technique is presented. To measure the echo reduction of a sample with this approach, the received signals are firstly focused according to the TR theory. Then, the sample is removed and the TR processing is again employed to realize the focus of the received signal.Finally, the echo reduction of the sample is evaluated with these focusing signals. Besides, to calibrate the measured echo reduction via the TR technique, a standard sample is employed to measure a constant coefficient that only depends on the measurement environment. An aluminum plate sample and a steel plate sample with the same size of 1.1 mxl.O m x0.005 m axe tested in a wave guide tank. The experimental results show that the calibrated values are well consistent with theoretical results under the free field at the measured frequency range of0.5-20 kHz. The relative errors of all the measured values are less than 10% and the values of the expanded uncertainty are less than 1.5 dB. The TR processing focuses the energy in spatial domain and temporal domain, so it can be used to measure the echo reduction of passive materials in the environments with reflections induced by boundaries and low frequency sources. | YAN Xiaowei LI Jianlong HE Zhiguang | 2016 | Chinese Journal of Acoustics2016，35，3： | 7 |
| 2 | Focusing in solids and application in acoustic imaging显示文摘Focusing in solids by surface transducer arrays(STA)and the acousticfield distribution on the focal axis are studied in this paper.The relation betweenthe source element width and the field strength at different order focuses is alsodiscussed.Numerical calculation is used to get the focal field distribution as theelement width is changed.Some practical problems such as the minimumdistinguishable frequency,the transversal and longitudinal resolution are investi-gated when this kind of focusing is used for NDT and acoustic imaging.Someexplorative experiments have been done to demonstrate the theory. | QIAO Donghai, WANG Chenghao ZHOU Yuying(Institute of Acoustics, Academia Sinica, Beijing 100080) | 1992 | Chinese Journal of Acoustics1992，11，4： | 5 |
| 3 | 33 ku protein associated several polypeptides with nearly the same molecular weight but not the same isoelectric point显示文摘The 33 ku protein, prepared from NaCI-treated PSII particles, has shown an single band by SDS-PAGE. After being dialyzed against the low-osmotic medium at 4癈, it has been found that the 33 ku protein degraded into several small fragments. This result suggests that the preparations of 33 ku protein probably contain some latent proteinases. it has also been found, by the 2-D electrophoresis and IEF, that the preparations of 33 ku protein not dialyzed against the low-osmotic medium contain several polypeptides with nearly the same molecular weight but not the same isoelectric point as the 33 ku protein. | Hui Yu Bin Kang Jie Wei Liangbi Li Tingyun Kuang | 2000 | Chinese Science Bulletin2000，45，1： | 3 |
| 4 | A method of laser focusing control in microlaser-induced breakdown spectroscopy显示文摘This paper presents a method for the automatic adjustment of the laser defocusing amount in micro-laser-induced breakdown spectroscopy. A microscopic optical imaging system consisting of a CCD camera and a 20× objective lens was adopted to realize the method. The real-time auto-focusing of the system was achieved by detecting the effective pixels of the light spot generated by the laser pointer. The focusing accuracy of the method could achieve 3 μm. The element concentrations of Mn and Ni in low-alloy steels were analyzed at a crater diameter of about 35 μm using the presented method. After using the presented method, the determination coefficients of Mn and Ni both exceeded 0.997, with the root-mean-square errors being 0.0133 and 0.0395, respectively. Scanning analysis was performed on the inclined plane and the curved surface by means of focusing control and non-focusing control. Ten characteristic spectral lines of Fe were selected as the analysis lines. With the focusing control, the average relative standard deviations obtained on the inclined plane and curved surface were both less than 5%, and much less than the values without focusing control, 14.6% and 40.39%. | 汪为 孙兰香 张鹏 郑黎明 齐立峰 董伟 | 2019 | Plasma Science and Technology2019，21，3： | 3 |
| 5 | Blood glucose management in the patient undergoing cardiac surgery: A review显示文摘Both diabetes mellitus and hyperglycemia per se are associated with negative outcomes after cardiac surgery. In this article, we review these associations, the possible mechanisms that lead to adverse outcomes, and the epidemiology of diabetes focusing on those patients requiring cardiac surgery. We also examine outpatient and perioperative management of diabetes with the same focus. Finally, we discuss our own efforts to improve glycemic management of patients undergoing cardiac surgery at our institution, including keys to success, results of implementation, and patient safety concerns. | Pingle Reddy Brian Duggar John Butterworth | 2014 | World Journal of Cardiology2014，6，11： | 3 |
| 6 | Experimental study on filtering,transporting, concentrating and focusing of microparticles based on optically induced dielectrophoresis显示文摘The key problem to be solved for the dielectrophoresis (DEP) application is to provide dynamically reconfigurable microelectrodes and low-cost methodology for bioparticle manipulation.The emergence of optically induced DEP (ODEP) based on photoconductive effect provides a potential solution for the above problem.In this paper,an ODEP chip is designed and fabricated,and the corresponding experimental platform was established,whereupon four types of particle manipulation regimes–filtering,transporting,concentrating and focusing based on ODEP are experimentally demonstrated and the operating performances are quantitatively analyzed.The experiment results show that the functions and performances of ODEP manipulation are heavily dependent on the geometrical shape,scales and speed of optical patterns,actuating signal frequency and the electric conductivity of the solution.The manipulation efficiency can increase by more than 50% via increasing the optical line width.Moreover,the efficiency is obviously affected by the inclination angle of the optical oblique lines in the manipulation of particle focusing.Additionally,the maximum velocity of particles increases with the increment of the inside radius and the thickness of the optical trapping ring.Particle manipulation efficiency is always related to signal frequency and solution conductivity,and empirically,satisfactory performance and high efficiency are obtained when the solution electric conductivity ranges from 5×10-4 S/m to 5×10-3 S/m. | ZHU XiaoLu,YIN ZhiFeng,GAO ZhiQiang & NI ZhongHua Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments,Southeast University,Nanjing 211189,China | 2010 | Science China(Technological Sciences)2010，53，9： | 3 |
| 7 | Spontaneous pneumomediastinum and Macklin effect:Overview and appearance on computed tomography显示文摘Spontaneous pneumomediastinum(SPM) is described as free air or gas located within the mediastinum that is not associated with any noticeable cause such as chest trauma.SPM has been associated with many conditions and triggers,including bronchial asthma,diabetic ketoacidosis,forceful straining during exercise,inhalation of drugs,as well as other activities associated with the Valsalva maneuver.The Macklin effect appears on thoracic computed tomography(CT) as linear collections of air contiguous to the bronchovascular sheaths.With the recent availability of multidetector-row CT,the Macklin effect has been seen in the clinical setting more frequently than expected.The aim of this review article is to describe the CT imaging spectrum of the Macklin effect in patients with SPM,focusing on the common appearance of the Macklin effect,pneumorrhachis,and persistent SPM with pneumatocele. | Sadayuki Murayama Shinji Gibo | 2014 | World Journal of Radiology2014，6，11： | 3 |
| 8 | Introduction to Progress in Natural Science:Materials International | | 2012 | Progress in Natural Science:Materials International2012，22，4： | 2 |
| 9 | Numerical simulation of flow focusing pattern and morphological changes in two-phase flow inside nozzle显示文摘The flow focusing nozzle is a new type of nozzle that performs effective atomization of the discrete phase by means of high-speed motion of the continuous phase.The flow pattern and its morphological changes have a significant effect on the atomization, but the influence of different parameters on the morphological change of the flow pattern remains unclear.The flow focusing pattern and morphological changes in the two-phase flow inside the nozzle were simulated numerically, based on the volume of fluid method.The results demonstrate that the ratio of the nozzle-to-capillary distance and capillary diameter, the gas–liquid velocity ratio, and capillary diameter have significant effects on the flow pattern.When the ratio of the nozzle-to-capillary distance H and capillary diameter D increases, or the capillary diameter D increases, the flow pattern tends to transform into a laminar form; however, when the gas–liquid velocity ratio V increases, the flow pattern tends to transform into a turbulence form.Furthermore, we define the cone-shaped expansion rate, cone-shaped focusing rate,and cone angle in order to study the morphological changes in the cone shape inside the nozzle.The results indicate that the morphological change of the cone shape and flow pattern transformation is interrelated.When the cone shape tends to be unstable, the flow pattern changes towards flow blurring, whereas, a stable cone indicates that the flow tends to exhibit a droplet pattern. | Jin Zhao Zhi Ning Ming Lü Geng Wang | 2019 | Chinese Journal of Chemical Engineering2019，27，1： | 2 |
| 10 | Far-field vector-diffraction of off-axis parabolic mirror under oblique incidence显示文摘Based on a full vector-diffraction theory, a detailed theoretical study is carried out, aiming at providing a clear insight into the effects of different focusing and off-axis parabola parameters on far-field vector-diffraction properties of an offaxis parabolic mirror in the presence of misalignments of the incoming beam. The physical origin of these effects is also explored. The results show that the far-field intensity profile is altered by the distortion-, coma-, and astigmatism-like aberrations, which are caused by oblique incidence rather than inherent aberrations for the off-axis configuration. The radius of 90% encircled energy also increases but does not change monotonically with incident beam size increasing, or rather,it first decreases and then increases. The focal shift strongly depends on the effective focal length and oblique incidence angle, but it is almost independent of the beam size, which affects the focusing spot patterns. The intensity distribution produces a higher astigmatic image with off-axis angle increasing. Coma-like aberration starts to become dominant with beam size increasing and results in larger curved propagation trajectory. The incident polarization also affects the intensity distribution. The variation in the Strehl ratio with oblique incidence angle strongly depends on the misalignment direction and beam size as well. In addition, we find that the difference in locus between the catacaustic and the diffraction focus in the meridian is small. But the locus of the sagittal foci is obviously different from the locus of the meridian foci and the catacaustic focus. Moreover, the peak intensity of the sagittal focus is maximum, and the ratio of the peak intensity to that in the meridian plane is approximately 1.5. Understanding these effects is valuable for assessing a practical focused intensity and describing the motion of charged particles under a strong electric field in ultraintense laser–matter interaction. | 曾夏辉 陈曦曜 | 2020 | Chinese Physics B2020，29，3： | 2 |
| 11 | A new journal on sustainable development of coal science and mining engineering launched by the China Coal Society and Springer显示文摘China Coal Society(CCS)and Springer have announced that they will launch a new authoritative journal with a total dedication on coal science and mining engineering.The new journal,International Journal of Coal Science and Mining Engineering(JCSME)will be launched in early 2014.JCSME aims to be a peer-reviewed academic OA journal focusing on key topics of coal scientific research and mining development. | | 2013 | 煤炭学报2013，38，12： | 2 |
| 12 | Ultrasonic beam focusing characteristics of shear-vertical waves for contact-type linear phased array in solid显示文摘We investigate the beam focusing technology of shear-vertical(SV) waves for a contact-type linear phased array to overcome the shortcomings of conventional wedge transducer arrays. The numerical simulation reveals the transient excitation and propagation characteristics of SV waves. It is found that the element size plays an important role in determining the transient radiation directivity of SV waves. The transient beam focusing characteristics of SV waves for various array parameters are deeply studied. It is particularly interesting to see that smaller element width will provide the focused beam of SV waves with higher quality, while larger element width may result in erratic fluctuation of focusing energy around the focal point. There exists a specific range of inter-element spacing for optimum focusing performance. Moreover, good beam focusing performance of SV waves can be achieved only at high steering angles. | 戴宇翔 阎守国 张碧星 | 2020 | Chinese Physics B2020，29，3： | 2 |
| 13 | Vertical focusing study in the central region of the CYCIAE-100 cyclotron显示文摘The vertical focusing is one of the primary problems in the central region of cyclotrons. This focusing effect brought about by the magnetic field is inclined to be weak near the center of the machine due to the fact that the flutter is small, while the electric focusing forces incurred from the dee gaps become very strong. Since the electric focusing effect is dependent on the RF phase, we have proceeded to carry out analytical calculations and numerical simulation about the vertical focusing in the central region of CYCIAE100, including magnetic focusing, electric focusing and the defocusing effect from the space charge effect. All the results have been used for the design of the central region for CYCIAE-100 and a good vertical focusing has been obtained. | 姚红娟 张天爵 管锋平 钟俊晴 | 2009 | Chinese Physics C2009，33，S2： | 1 |
| 14 | Research on Dielectric Focusing Lens Antenna for HPM Atmospheric Breakdown Experiments显示文摘To distinguish the dielectric surface breakdown from the atmospheric breakdown, one method for atmospheric breakdown experiment by loading dielectric focusing lens is proposed. The focusing characteristics of dielectric focusing lens are investigated for the microwave frequency on the order of 1.3GHz to 9.3GHz, the lens focal length on the order of 0.3m to 0.9m and the dielectric constant on the order of 0.3 to 0.9. Simulations show that higher frequency, shorter focal length, and fitter dielectric constant result in better focus effect that the rising and falling edges of electric field strength change faster near the focus which is closer to the theoretical value. A dielectric focusing lens for the S-band is optimally designed with the polytetrafluoroethylene of 0.32 m thickness, 0.6m diameter,and 0.4m focal length. The focus indicator of dielectric lens is measured and the atmospheric breakdown experiment is carried out. The experimental values of atmospheric breakdown are consistent with the theoretical values. The electric field strength with the lens at the focus is 5–6times greater than that without focusing lens. The image of atmospheric breakdown by the dielectric lens focusing method experiment is clearer than that by the direct radiation method. | YU Daojie CHAI Mengjuan ZHOU Dongfang ZHOU Changlin WEI Jinjin HU Junjie CAI Beibing ZHAO Tongcheng | 2019 | Chinese Journal of Electronics2019，28，1： | 1 |
| 15 | High frequency acoustic microscopy with Fresnel zoom lens显示文摘The acoustic field distributions and the convergent beams generated by the planar-structure Fresnel zone transducers on solid surface are investigated. Because only 0 and 180 degree phase transducers are used, an imaging system with the Fresnel zoom lens could work at very high frequency, which overcomes the frequency limit of the traditional phased array acoustic imaging system. Simulation results are given to illustrate the acoustic field distributions along the focal axis and the whole plane as well. Based on the principle of scanning of the focus with the change of frequency for the excited signal, an experimental imaging system is also built. Acoustic Fresnel zone transducers are fabricated at center frequency of 400 MHz. Measurements and detections of the known hole flaws at different depths of the fused quartz sample are presented to show that the imaging system with Fresnel zoom lens could move its focus by only changing the frequency of the excited signal. | QIAO DongHai LI ShunZhou WANG ChengHao | 2007 | Science China(Physics,Mechanics & Astronomy)2007，50，1： | 1 |
| 16 | Glutathione S-Transferase Isoenzymes as Marker in Preneoplasia of Rat Chemical Hepatocarcinogenesis显示文摘It has been generally accepted that about 85% of cancers are caused by chemical factors and the chemically induced carcinogenic process can be divided into two or three stages, i. e. initiation and promotion, or together with further progression. The initiation is usually considered to be an irreversible process, but it can be blocked to further progress to cancer. For this reason, searching of objective markers for identifying initiated cells has played an important role in defining the preneoplastic lesion. So far, a large number of studies have been carried out on this object, including biochemistry, histopathology, histochemistry, immunohistochemistry, etc., and nearly thirty histochemical and other phenotypic changes have been found associated with the putative preneoplastic liver | 左瑾 方福德 丁濂 谢大英 | 1993 | Chinese Science Bulletin1993，38，7： | 1 |
| 17 | Study on Energy Spectrum Instability in the Processes of Propagating and Breaking of Focusing Waves显示文摘Based on phase focusing theory, focusing waves with different spectral types and breaking severities were generated in a wave flume. The time series of surface elevation fluctuation along the flume were obtained by utilizing 22 wave probes mounted along the mid-stream of the flume. Based on the wave spectrum obtained using fast Fourier transform(FFT), the instability characteristics of the energy spectrum were reported in this paper. By analyzing the variation of total spectral energy, the total spectral energy after wave breaking was found to clearly decrease, and the loss value and ratio gradually increased and tended to stabilize with the enhancement of breaking severity for different spectral types. When wave breaking occurred, the energy loss was primarily in a high-frequency range of f/fp>1.0, and energy gain was primarily in a low-frequency range of f/fp<1.0. As the breaking severity increased, the energy gain-loss ratio decreased gradually, which demonstrates that the energy was mostly dissipated. For plunging waves, the energy gain-loss ratio reached 24% for the constant wave steepness(CWS) spectrum, and was slightly larger at approximately 30% for the constant wave amplitude(CWA) spectrum, and was the largest at approximately 42% for the Pierson-Moskowitz(PM) spectrum. | ZHANG Yi-hui LIANG Shu-xiu SUN Zhao-chen | 2019 | China Ocean Engineering2019，33，1： | 1 |
| 18 | Moving chemical reaction boundary and isoelectric focusing (Ⅲ)——Comparisons between the transference numbers of H+ in the acids HBr, HCl and HI, and OH- in the alkali KOH | 曹成喜 | 1999 | Progress in Natural Science:Materials International1999，9，8： | 1 |
| 19 | Breaking the diffraction limit in far field by planar metalens显示文摘Optical lens is of fundamental importance in both scientific researches and industrial communities,especially for the aspects of optical focusing and imaging.In traditional optics,the light modulation property is limited by the Rayleigh Criterion(0.61λ/NA),and therefore the development of an ideal lens that produces sub-diffraction limit focusing and imaging has been a dream of lens makers all the time.Intensive | Fei Qin MingHui Hong | 2017 | Science China(Physics,Mechanics & Astronomy)2017，60，4： | 1 |
| 20 | 精神医学中的生物统计学(10):进行临床试验时对缺失数据的预防和处理(英文) | Kousick BISWAS | 2012 | 上海精神医学2012，24，04X： | 1 |
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