Wave Processes and Mass Transfer on the Copper-Stainless Steel Interface under Solid Phase Bonding by High-Temperature Rolling

The paper presents the study of hierarchy of deformation wave-processes from nano- to macro-structural level, which takes place in dissimilar materials, bonded by high-temperature vacuum rolling in solid phase. The focus was on the processes that occur on the interface of the bonded materials: mass trasfer of impurities and alloying elements stimulated by deformation, the study of nano- and micro-hardness.

Analysis of Energy Characteristics in the Process of Freak Wave Generation

The energy characteristics in the evolution of the wave train are investigated to understand the inherent cause of the freak wave generation. The Morlet wavelet spectrum method is employed to analyze the numerical, laboratory and field evolution data of this generation process. Their energy distributions and variations are discussed with consideration of corresponding surface elevations. Through comparing the energy characteristics of three cases, it is shown that the freak wave generation depends not only on the continuous transfer of wave train energy to a certain region where finally the maximum energy occurs, but also on the distinct shift of the converged energy to high-frequency components in a very short time. And the typical energy characteristics of freak waves are also given.

Voltage Characteristic Analysis of Ultra-high Voltage Half-wavelength Transmission System Based on Wave Process Method

The voltage characteristics of a half-wavelength transmission(HWLT)system lack mechanism explanation and systematic summary.In this paper,both the steady-state and fault voltage characteristics are analyzed and explained based on the wave process method.An analysis model is established for HWLT lines and wave propagation equations with different terminal conditions are deduced.For steady-state conditions,voltage profiles along HWLT lines are depicted and partial overvoltage occurs when there is an overload or low-power factor.In addition,fault voltage characteristics are analyzed under load-rejection or short-circuit conditions.The series resonance overvoltage will happen when short-circuit faults occur at certain positions and its peak value is influenced by grid strength or fault type.Furthermore,a refined transmission line model is presented to consider non-ideal factors and simulation results demonstrate that geomorphic conditions and electromagnetic environments influence line voltage characteristics to a certain extent.

Numerical analysis of tunnel reinforcing influences on failure process of surrounding rock under explosive stress waves

Based on mesoscopic damage mechanics, numerical code RFPA2D (dynamic edition) was developed to analyze the influence of tunnel reinforcing on failure process of surrounding rock under explosive stress waves. The results show that the propagation phenomenon of stress wave in the surrounding rock of tunnel and the failure process of surrounding rock under explosive stress waves are reproduced realistically by using numerical code RFPA2D; from the failure process of surrounding rock, the place at which surrounding rock fractures is transferred because of tunnel reinforcing, and the rockfall and collapse caused by failure of surrounding rock are restrained by tunnel reinforcing; furthermore, the absolute values of peak values of major principal stress, and the minimal principal stress and shear stress at center point of tunnel roof are reduced because of tunnel reinforcing, and the displacement at center point of tunnel roof is reduced as well, consequently the stability of tunnel increases.

The Process of a Laser-Supported Combustion Wave Induced by Millisecond Pulsed Laser on Aluminum Alloy

We study the process of a laser-supported combustion wave （LSCW） when an aluminum alloy is irradiated by a millisecond pulse laser based on the method of laser shadowgraphy. Under the condition of different laser parameters, the obtained results include the velocity, ignition threshold of LSCW and the variation law. The speed of LSCW increases with the laser energy under the same irradiation laser pulse width, and the speed of LSCW reduces with the increase of the laser pulse width under the same irradiation laser energy. Moreover, the ignition time of LSCW becomes shorter by increasing the laser number of the pulse and is not effected by changing the frequencies, when keeping the laser pulse width and energy unchanged. The results of the study can be applied in the laser propulsion technology and metal surface laser heat treatment, etc.

Analysis of a Cold Wave Weather Process in Chengdu in March 2010

[Objective] The aim was to analyze one cold wave weather process in Chengdu in March in 2010.[Method] Based on the NCEP 1°×1° 6 h interval reanalysis data and daily observation data,using synoptic analysis and diagnosis methods,and combining with the cold wave forecast index in spring of Sichuan,a cold wave event covering the whole region between March 21 and 24,2010 was analyzed from the aspects of circulation background,influencing weather systems and weather causation.[Result] Results showed that the 500 high-altitude cold vortex,700-850 hPa low layer shear,and ground cold front were the main systems that influenced this cold wave;there was a ridge from Lake Balkhash across Lake Baikal at 500 hPa.The early stage of the process was controlled by the high pressure ridge and the temperature was increasing obviously.The daily mean temperature was high.The range of cold high pressure was large and the central intensity was 1 043.0 hPa;the cold air was strong and deep which was in accordance with the strong surface temperature reduction center.The strong north airstream of Lake Balkhash to Lake Baikal,ground cold high pressure center intensity changes,north and south ocean pressure and temperature differences,850 hPa temperature changes,cold advection movement route and intensity were considered as reference factors for the forecast of cold wave intensity.[Conclusion] The study provided theoretical basis for improving the forecast ability of cold wave weather.

Scattering Process of Internal Waves Propagating over a Subcritical Strait Slope onto a Shelf Region

The scattering process, which means the redistribution of energy fluy in modenumber space, is analyzed for internal waves propagating from the abyssal ocean onto a subcritical strait slope and then a shelf region. In light of Wunsch's work, the waves are analytically expressed as superimposition of eigensolutions. Two parameters have evident effects on the distribution of energy flux in the shelf region: one is the ratio of water depth in the shelf region to that in the abyssal ocean and the other is the ratio of the slope of the internal tide rays to the topographic slope. Generally, there are two patterns of energy flux distribution: the energy flux is focused around one modenumber or focused around two modenumbers. In any case, the range of modenumbers where energy flux is distributed is narrow.

Numerical simulation of non-gaussian process of wind waves

In this paper further mathematical analysis on 'correlation transfer technique' by Polge el al. is carried out, the tenable conditions and the extent of suitability for the said method are proved as well. In consideration of the influence of skewness of the sea surface elevation on spectral shape, a 'quasi-correlation transfer techique' is developed by the modification of the simulated target spectrum. Meanwhile, the numerical simulation of the non-Gaussian process of wind waves is carried out in view of the two conditions of the surface elevation probability distribution and the spectrum. By using its simulated results, the influence of skewness of the sea surface elevation on two parameters in the distribution of wave heights (which had been fitted by using the Weibull distribution) is analysed. The 'quasi- correlation tranfer technique' is verified and compared with the selection wave data observed in the Jiaozhou Bay in the period of 1980 to 1981. Results make clear (hat, as far as the statistical distribution of the wave heights and the distribution of the maximum (minimum) values of the sea surface elevation are concerned, the said method is obviously superior to the conventional mothed of the linear wave superposition, and that the simulated results are closer to the observation data.

A real time processing system of seismic waves using personal computers-Function and characteristics

Seismological Bureau of Sichuan Province, Chengdu 610041, China2) Center for Analysis and Prediction, State Seismological Bureau, Beijing 100036, China3) Observation Center for Prediction of Earthquakes and Volcanic Eruptions, Faculty of Sciences, Tohoku University, Sendai 98077, Japan

Measurement of intensity difference squeezing via non-degenerate four-wave mixing process in an atomic vapor

We report the measurement of the intensity difference squeezing via the non-degenerate four-wave mixing process in a rubidium atomic vapor medium. Two pairs of balanced detection systems are employed to measure the probe and the conjugate beams, respectively. It is convenient to get the quantum shot noise limit, the squeezed and the amplified noise power spectra. We also investigate the influence of the input extra quadrature amplitude noise of the probe beam. The influence of the extra noise can be minimized and the squeezing can be optimized under the proper parameter condition. We measure the -3.7-dB intensity difference squeezing when the probe beam has a 3-dB extra quadrature amplitude noise. This result is slightly smaller than -4.1 dB when the ideal coherent light （no extra noise） for the probe beam is used.

Intensification of the Banana Drying Processes by Using EFL Electromagnetic Waves

Drying of the banana in the hot water has a negative impact on the quality of the product and drying effect. The purposes of this study are increasing the drying rate, using the relatively low temperature to improve the quality (40℃, 50℃ and 60℃) and investigate the use of electromagnetic waves to increase the drying speed. Therefore, experiments are performed using 5 kHz,10 kHz and 15 kHz low frequency electromagnetic waves in the air velocity values of 0.5 m/s, 1 m/s, 1.5 m/s and 2 m/s and 40℃, 50℃, 60℃ centigrade degrees of air blast in a special compartment. Mathematical model of the drying process has been created as using the electrical circuits methods and experimental results. As a result, a simple equation describing the drying process has been obtained. Nonlinear expression of the diffusion coefficient for a different situation in this equation has been identified for the first time. The obtained theoretical results and experimental results have been provided a good agreement. This study is considered to be useful for all studies in the drying area.

A Numerical Model of Coastal Processes of Sand Beaches Based on Long-Term Wave Series

A numerical model of shoreline change of sand beaches based on long-term field wave data is proposed, the explicit and implicit finite difference forms of the model are described, and an application of the model is presented. Results of the application indicate that the model is sensitive to the order of the input wave data, and that the effects of long-term wave series and the effects of the mean annual wave conditions on the model are different. Instead of a single wave condition, the wave series will make the calibration and the verification of the model more practical and the results of the model more reasonable.

ASYMPTOTICS OF THE SOLUTIONS TO STOCHASTIC WAVE EQUATIONS DRIVEN BY A NON-GAUSSIAN LéVY PROCESS

In this article, we consider the long time behavior of the solutions to stochastic wave equations driven by a non-Gaussian Levy process. We shall prove that under some appropriate conditions, the exponential stability of the solutions holds. Finally, we give two examples to illustrate our results.

无血清培养杂交瘤细胞在WAVE-25生物反应器的工艺研究

目的:在WAVE-25生物反应器上,探讨抗人CD52杂交瘤细胞无血清流加培养方式的工艺条件,通过多种抗体质量检测加以验证,建立规模化的生产工艺,为后期的工艺放大提供参考。方法:探索无血清培养CD52杂交瘤细胞在WAVE-25生物反应器的工艺参数,在反应过程中依据活细胞密度、活率、pH值、溶氧以及免疫球蛋白G(IgG)含量、葡萄糖(Gluc)、谷氨酰胺(L-Gln)、乳酸(Lac)、铵根离子(NH_(4)^(+))等生长代谢参数进行过程监测和调控;通过蛋白纯化,利用流式细胞术,十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)和分子排阻高效液相色谱(SEC-HPLC)对CD52单克隆抗体纯品(简称CD52纯抗)进行特异性和纯度的检测和鉴定。结果:无血清培养CD52杂交瘤细胞通过流加培养方式在WAVE-252L生物反应器可稳定大规模培养,蛋白纯化后获得的CD52纯抗产率和质量得到显著提高,产率从100 mg/L提高至350 mg/L,提高了3.5倍;纯度从92%提高至100%;相同浓度下荧光强度提高了69%。结论:CD52杂交瘤细胞在WAVE-25生物反应器可大规模培养,通过工艺参数和反应过程中生化指标的调控获得的CD52纯抗产率和质量都有显著的提高,可为后续的大规模化生产提供参考。

基于高压气体驱动的爆炸波模拟激波管冲击波衰减历程控制方法

基于高压气体驱动的爆炸波模拟激波管,一般采用驱动段、喉部、膨胀段的结构形式,可产生特征与爆炸波接近的模拟冲击波,是实验室中开展长正压作用时间爆炸毁伤效应研究的理想平台。通过调整激波管的变截面结构和驱动段形状,实现冲击波超压衰减历程的控制,是此类爆炸波模拟激波管设计面临的核心问题之一。基于实验室现有的爆炸波模拟激波管结构,建立了激波管内一维流动数值计算模型;参考统计学理论,提出了基于决定系数的激波管模拟冲击波与标准爆炸波相似度评价方法;进而以变截面激波管的流动特性为基础,研究了驱动段形状对冲击波衰减历程的影响机理。研究结果表明:采用距离喉部越远、截面直径越小的驱动段形状,以决定系数为量化标准、优化驱动段形状,控制稀疏波、压缩波在激波管内的运动过程,可以获得接近于爆炸波指数衰减特征的模拟冲击波。

一种基于人体生物电信号分析的健康监测实验系统的设计

设计了一种基于反射式光电容积脉搏波描记法(PhotoPlethyMography,PPG)进行心率变异性(Heart Rate Variability,HRV)短时分析的实验系统,使用国产主控处理器和脉搏波采集器采集脉搏波数据,经过滤波预处理、心率周期检测、HRV数据计算、MATLAB AppDesigner显示波形和数据存储,通过分析得到了关于人体HRV的健康监测数据。

High-Resolution Broadband Millimeter-Wave Astrophysical Spectrometer with Triple Product Acousto-Optical Processor

An advanced conceptual design of a high-bit-rate triple product acousto-optical processor is presented that can be applied in a number of astrophysical problems. We briefly describe the Large Millimeter Telescope as one of the potential observational infrastructures where the acousto-optical spectrometer can be successfully used. A summary on the study of molecular gas in relatively old (age > 10 Myr) disks around main sequence stars is provided. We have identified this as one of the science cases in which the proposed processor can have a big impact. Then we put forward triple product acousto-optical processor is able to realize algorithm of the space-and-time integrating, which is desirable for a wideband spectrum analysis of radio-wave signals with an improved resolution providing the resolution power of about 105 - 106. It includes 1D-acousto-optic cells as the input devices for a 2D-optical data processing. The importance of this algorithm is based on exploiting the chirp Z-transform technique providing a 2D-Fourier transform of the input signals. The system produces the folded spectrum, accumulating advantages of both space and time integrating. Its frequency bandwidth is practically equal to the bandwidth of transducers inherent in acousto-optical cells. Then, similar processor is able to provide really high frequency resolution, which is practically equal to the reciprocal of the CCD-matrix photo-detector integration time. Here, the current state of developing the triple product acousto-optical processor in frames of the astrophysical instrumentation is shortly discussed.

天然酯绝缘油对220 kV电力变压器主绝缘性能的影响分析

为了分析天然酯绝缘油对高压变压器绝缘性能的影响,本研究以一台220 kV电力变压器为研究对象,对其进行波过程计算得到雷电冲击全波下的节点电位与油道梯度电压,并建立变压器主绝缘电场计算模型得到工频及雷电全波电压下的电场分布,再计算绝缘裕度。结果表明:天然酯绝缘油变压器在工频下主绝缘裕度较大,而在雷电全波下该值较小。通过改进天然酯绝缘油变压器的绝缘结构,可缩小天然酯绝缘油变压器中压、高压绕组间主绝缘距离约6%,增大调压绕组匝绝缘厚度及角环半径,可使其在雷电全波下的绝缘裕度最小值提高15%,同时有效节约了成本。

江苏寒潮天气过程风险预评估方法研究

利用江苏省1961—2020年70个国家级及1300多个区域自动气象站同时段的日最低气温重构数据,选取最低气温48 h最大降温幅度、累计降温幅度、过程日极端最低气温和寒潮过程持续天数共4个要素作为寒潮灾害气象致灾因子,综合信息熵权法和专家打分法确定各致灾因子权重,构建寒潮过程致灾危险性评估模型,形成致灾危险性指数长时间序列,采用百分位法确定危险等级。基于智能网格气温预报数据,计算寒潮过程预估致灾危险性指数,在此基础上结合承灾体暴露度及脆弱性信息,构建寒潮过程风险预评估模型,对高分辨率人口、国内生产总值(Gross Domestic Product,GDP)和小麦等承灾体进行风险预估,同时考虑前期气温对小麦生长的影响,修正了小麦脆弱性指标。结果表明:(1)江苏省历年寒潮过程发生频次总体呈现20世纪后40年多、21世纪前20年少的态势,北部地区发生频次显著多于南部地区;寒潮过程的气象致灾因子强度大体上具有西部强于东部、北部强于南部的分布特征;(2)通过对2022年11月28日—12月3日江苏全省性寒潮天气过程的个例分析,可以得出与实际灾情基本相符的寒潮天气过程的致灾危险性预评估和风险预估结果。

受限空间中斜爆震波波系结构及其演化

为了研究真实发动机中受限空间内斜爆震波的宏观波系结构,采用欧拉方程结合详细反应机理的数值模拟方法,开展了受限空间的斜爆震波的数值模拟,分析了不同转折角下斜爆震波波系结构及其演化过程。结果表明,在上壁面转折处膨胀波的影响下,斜爆震波反射形成的马赫杆在前移过程中衰减,最终会在上扩张壁面附近形成高温回流区和低温三角区的稳定结构,三角区由转折处波系、回流区和下游斜爆震波组成。随转折角增大,最终在转折处点处依次形成激波、弱压缩波和膨胀波,与斜爆震波相交,交点下游的斜爆震波衰减,在末端出现解耦现象。