Effects of Global Value Chain Position on the Carbon Emissions of Manufacturing Industry in China: An Empirical Study Based on the STIRPAT Model

Based on the input-output data from the World Input-Output Database( WIOD),the global value chain( GVC) position of China's manufacturing industry from 2003 to 2014 was calculated,and the relationship between the carbon emissions and global value chain position of China's manufacturing industry was studied based on the improved STIRPAT model. The results show that the improvement of global value chain position could significantly reduce the carbon emissions of China's manufacturing industry. In addition,foreign investment and energy structure hindered the low-carbon development of China's manufacturing industry. The effects of population size and research intensity on the carbon emissions of manufacturing industry were not significant. In the process of participating in the global value chain,China's manufacturing industry should effectively reduce carbon emissions by strengthening environmental regulation,optimizing energy structure and improving production technology.

The Effect of Catena Position on Greenhouse Gas Emissions from Dambo Located Termite (<i>Odontotermes transvaalensis</i>) Mounds from Central Zimbabwe

Methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2)O) are greenhouse gases (GHGs) which cause global warming. Natural sources of GHGs include wetlands and termites. Previous studies have quantified GHG emissions from upland termites and no study has reported GHG emissions from seasonal wetlands (dambo) located termite mounds. The objective of this study was to evaluate the effect of dambo catena position on termite mound distribution and GHG emissions. It was hypothesized that mound density and GHG emissions from Odontotermes transvaalensis mounds, vary with catena position. The evaluated catena positions were margin, mid-slope, lower slope and bottom. Mound density was significantly lower in the bottom when compared to the other catena positions. The mean GHG fluxes were 88 μg m2 hr-1, 0.78 mg m2 hr-1 and 1361 mg m2 hr-1 for N2) O, CH4 and CO2 respectively. Fluxes varied with catena position and were 0.48, 0.72, 1.35 and 0.79 mg m-2 hr-1 for CH4 , and 1173.7, 1440.7, 1798.7 and 922.8 mg m-2 hr-1 for CO2 in the margin, mid-slope, lower slope and the bottom catena position respectively. For N2) O, there were no significant differences between catena positions. It was concluded that dambo located Odontotermes transvaalensis termite mounds are an important source of GHGs, and emissions varied with catena position for CO2 and CH4.

Effect of Electron and/or Ion Nonthermality on Dust Acoustic Wave Propagation in a Complex Plasma in Presence of Positively Charged Dust Grains Generated by Secondary Electron Emission Process

In this paper we have developed a model to study the role of both electron and ion nonthermalities on dust acoustic wave propagation in a complex plasma in presence of positively charged dust grains. Secondary electron emission from dust grains has been considered as the source of positive dust charging. As secondary emission current depends on the flux of primary electrons, nonthermality of primary electrons changes the expression of secondary emission current from that of earlier work where primary electrons were thermal. Expression of nonthermal electron current flowing to the positively charged dust grains and consequently the expression of secondary electron current flowing out of the dust grains have been first time calculated in this paper, whereas the expression for nonthermal ion current flowing to the positively charged dust grains is present in existing literature. Dispersion relation of dust acoustic wave has been derived. From this dispersion relation real frequency and growth rate of the wave have been calculated. Results have been plotted for different strength of nonthermalities of electrons and ions.

Effects of sonic speed on location accuracy of acoustic emission source in rocks

To quantitatively study the location errors induced by deviation of sonic speed, the line and plane location tests were carried out. A broken pencil was simulated as acoustic emission source in the rocks. The line and plane location tests were carried out in the granite rod using two sensors and the cube of marble using four sensors, respectively. To compare the position accuracy between line and plane positions, the line poison test was also carried out on the marble surface. The results show that for line positioning, the maximum error of absolute distance is about 0.8 cm. With the speed difference of 200 m/s, the average value of absolute difference from the position error is about 0.4 cm. For the plane positioning, in the case of the sensor array of 30 cm, the absolute positioning distance is up to 8.7 cm. It can be seen that the sonic speed seriously impacts on the plane positioning accuracy. The plane positioning error is lager than the line positioning error, which means that when the line position can satisfy the need in practical engineering, it is better to use the line position instead of the plane location. The plane positioning error with the diagonal speed is the minimum one.

Improved Study on Position Measurement System for Linear Motor Applied in Electromagnetic Launch System

The linear motor applied in electromagnetic emission system uses a closed loop position control strategy,which needs a set of position measurement system with high reliability,high resolution and integration to achieve real-time acquisition and analysis of position signals.The existing position controller is based on the simple logic chip design without memory function,and does not have the storage analysis and preprocessing function to position signals.Therefore,the system has insufficient scalability,low integration and reliability.Aiming at the improvement of the existing position measurement system,an intelligent position measurement system integrating the functions of position signals acquisition,processing and uploading,data storage and analysis is proposed in this paper,and its working principle and system composition are discussed in detail.The position,speed and acceleration obtained on the electromagnetic emission platform are in good agreement with the expected value of the system.As results,the feasibility and accuracy of the improved integrated intelligent position measurement system are verified,and the control performance of the system is also satisfied well,which can be good guidance and reference for subsequent engineering practice.

Combustion and NO_(x)Emission Characteristics of Coal Slime Solid Waste at Different Feeding Positions

The NO_(x)emission of coal slime burned in circulating fluidized bed(CFB)boilers could hardly meet the increasingly strict standards in China.Feeding coal slime from the top of furnace led to uneven combustion in furnace and cyclones,short residence time and overheated tail heating surface.The effects of feeding positions on the combustion uniformity and pollutant emission characteristics of coal slime were studied.The experimental results showed that the coal slime combustion was more uniform when feeding from the front wall and longer residence time was conducive to the control of NO_(x)emission.When the boiler temperature and excess air ratio were almost identical,the initial NO_(x)emissions were 45.0 mg·m^(−3)and 70.7 mg·m^(−3)when feeding from the front wall and the top of furnace,respectively;the NO_(x)emission was cut down 36.35%when feeding from the front wall,successfully meeting the ultra-low NO_(x)emission standard of China.The adoption of feeding from the front wall greatly reduced the original emission of NO_(x);the operation costs in the practical applications were saved to a large extent.

点火位置对X型转子发动机燃烧过程的影响

为探究X型转子发动机独特燃烧室内复杂湍流场与点火位置的耦合作用对混合气燃烧过程的影响,建立了X型转子发动机的三维计算流体动力学模型,并与试验结果进行对比验证,数值研究了不同点火位置下X型转子发动机缸内燃烧过程,揭示了点火位置对火焰传播、燃烧特性及污染物形成的影响规律。结果表明,在压缩末期,X型转子发动机燃烧室内形成了包括涡流和单向流的复杂湍流场,这与点火位置的耦合作用显著影响火焰传播过程。为了获得较高火焰传播速度,点火位置不宜布置在漩涡区处。点火位置位于凹坑中部时,可以充分利用四周空间和涡团与单向流场过渡处形成的较高速度场加速火焰传播,从而提前燃烧重心,增加放热速率,而且峰值压力提高了25%,指示热效率超过30%;同时其也具有较低的HC和CO排放量;但是由于其缸内峰值温度较大,导致NO排放量增加。

双向机制下企业自愿碳减排的三方博弈模拟

工业企业碳减排对平衡环境保护和经济发展尤为重要。基于政府和消费者双向机制探究企业自愿碳减排的影响因素,根据政府正向激励机制和消费者反向倒逼机制构建政府、企业和消费者三方演化博弈模型,分析了各参与方策略选择的演化稳定性,从系统动力学角度探讨三方主体策略选择不同时各个参数对企业自愿碳减排的影响机制,进一步分析了三方博弈系统中均衡点的稳定性。结果表明:企业选择自愿减排策略的概率与消费者低碳消费概率和政府非物质激励带给企业的收益额、减排成本补贴率、政府奖金、企业碳披露损失额等参数呈正相关;与企业的低碳营销费用、绿色积分价值、消费污染等参数呈负相关。最后,利用MATLAB 2016a进行数值仿真,验证了以上结论,并结合实际提出相关建议。

面向欧盟《电池和废电池法规》动力电池碳足迹的减排路径与情景

2023年8月17日,欧盟《电池和废电池法规》(简称新《电池法》)在欧盟正式生效,并引入电池护照概念。根据该法规,从2025年2月18日起,动力电池需提供电池的碳足迹信息,以突破欧盟贸易壁垒,促进国内动力电池的出口。本文以NCM三元5系电池为研究对象,对动力电池的碳足迹进行了梳理与分析,同时按照欧盟新《电池法》的要求,分析了在不同情景模式下电池的碳足迹减排情况。结果发现:①动力电池的碳排放减排关键在于正极材料,其碳排放占电芯原材料总碳排放的58%,其中正极前驱体在正极材料碳排放中的占比高达85%,其次是能耗碳排放,占电芯总碳排放的20%;②在使用可再生能源的情况下,5系电芯产品的碳足迹排放最低可以减少2.73%,最高可减少13.69%,其次仅使用正极再生材料减排,则5系电芯产品的碳足迹排放最低可减少1.81%,最高可减少7.86%;③在正极再生材料与可再生能源结合使用的情况下,5系电芯产品的碳足迹排放最低可减少4.55%,最高可减少21.55%。

Time-resolved characteristics of a nanosecond pulsed multi-hollow needle plate packed bed dielectric barrier discharge

In this paper,self-designed multi-hollow needle electrodes are used as a high-voltage electrode in a packed bed dielectric barrier discharge reactor to facilitate fast gas flow through the active discharge area and achieve large-volume stable discharge.The dynamic characteristics of the plasma,the generated active species,and the energy transfer mechanisms in both positive discharge(PD)and negative discharge(ND)are investigated by using fast-exposure intensified charge coupled device(ICCD)images and time-resolved optical emission spectra.The experimental results show that the discharge intensity,number of discharge channels,and discharge volume are obviously enhanced when the multi-needle electrode is replaced by a multihollow needle electrode.During a single voltage pulse period,PD mainly develops in a streamer mode,which results in a stronger discharge current,luminous intensity,and E/N compared with the diffuse mode observed in ND.In PD,as the gap between dielectric beads changes from 0 to250μm,the discharge between the dielectric bead gap changes from a partial discharge to a standing filamentary micro-discharge,which allows the plasma to leave the local area and is conducive to the propagation of surface streamers.In ND,the discharge only appears as a diffusionlike mode between the gap of dielectric beads,regardless of whether there is a discharge gap.Moreover,the generation of excited states N_(2)^(+)(B^(2)∑_(u)^(+))and N2(C^(3)Π_(u))is mainly observed in PD,which is attributed to the higher E/N in PD than that in ND.However,the generation of the OH(A^(2)∑^(+))radical in ND is higher than in PD.It is not directly dominated by E/N,but mainly by the resonant energy transfer process between metastable N_(2)(A^(3)∑_(u)^(+))and OH(X^(2)Π).Furthermore,both PD and ND demonstrate obvious energy relaxation processes of electron-to-vibration and vibration-to-vibration,and no vibration-to-rotation energy relaxation process is observed.

基于新型阵列的储罐底板声发射定位方法

针对传统声发射源定位方法对储罐底板中心位置附近声发射信号接收不佳的问题,设计出一种8⁃4⁃2⁃1型伞状定位阵列,通过改变定位传感器组合,并将模式识别技术融入到新型阵列定位算法中,解决了罐底定位容易出现的漏定位和伪定位等问题,最后通过对比试验对该定位阵列的效果进行验证。试验结果表明,新型定位算法对罐底中心位置的定位精度提升了10.99%,重复定位、伪定位问题对定位结果的影响降低了31.22%。

基于声发射技术的煤矿巷道掘进机定位方法

声发射技术能够监测设备运行过程中产生的声波,通过分析这些声波的传播特性可以准确确定掘进机的位置。基于此,详细介绍声发射技术的基本原理,并通过实验分析该技术在煤矿巷道掘进机定位中的应用效果。实验结果表明,声发射技术不仅能够提供高精度的定位服务,而且能在煤矿巷道掘进过程中实时更新位置信息,有效提升掘进作业的安全性和效率。

基于动力定位技术的火电厂碳排放实时监测系统

为提升火电厂碳排放监测效果,设计一种基于动力定位技术的火电厂碳排放实时监测系统。首先设计火电厂碳排放在线监测装置,在气体浓度反演模块中,应用最小二乘法拟合法与多元函数求极值法实施测量气体的浓度反演。在烟气定位模块中实施火电厂烟气定位与测量。利用设计系统对某火电厂实施碳排放实时监测,测试结果表明,设计系统能够实现多处测点的火电厂碳排放实时监测,监测结果与实际情况相符;测点处采样探头上落下的烟尘量非常轻微,最低仅为0.005 mm,能够实现烟气定位与烟气差压测量,实用性能良好。

UWB技术在煤矿精准定位与能效管理中的应用

UWB(Ultra Wide Band,超宽带)技术在煤矿精准定位与能效管理中的应用研究日益深入。介绍了UWB技术的原理及其在煤矿环境下应用的优势,探讨了该技术在人员定位、设备跟踪、辅助运输等方面的具体应用。UWB技术的应用还显著提高了煤矿安全管理水平,优化了生产流程,实现了减人提效。同时,借助UWB技术实现的精准管理,有效降低了能源消耗,促进了节能减排。对UWB技术在煤矿中的实施挑战及解决方法的探讨,为煤矿智能化转型提供了理论依据和实践指导。

The establishment of crystal position look-up table for positron emission tomography with block detectors

A method has been developed to establish the crystal position look-up table for positron emission tomography with block detectors. It is based on the principle that the counts in crystal position histogram obey the Gaussian mixture model (GMM). This method has taken full consideration of the characteristics of the GMM and the detector itself. The experimental results have proved that it is simple, reliable, and universal.

Generation of reactive atomic species of positive pulsed corona discharges in wetted atmospheric flows of nitrogen and oxygen

The emission spectra of excited radicals（OH（A^2E）,O（3p^3 P）,Hα（3P）） and emissive species（N2^＋（B^2∑u^＋）,N2（C3Πu）） produced by positive pulsed high-voltage needle-plane corona discharges in atmospheric N2 and O2 flows wetted with 10%H2O at 80 ℃ are used to investigate the relative concentrations of the produced radicals.The results indicate that the tendencies of the concentrations of radicals with discharge conditions are similar to each other due to their similar excitation processes by electron collision.The influence of oxygen flow mixed with the nitrogen flow on the emission intensities of O（3p^5P → 3s^5S2^0.）,Hα（3P → 2S）,N2＋（B^2∑u^＋ → X^2∑g＋0-0）,and N2（C^3Πu → B^3Πg 1-0） is presented.When the flow rate of oxygen addition is varied from 0-30 ml min^-1,the emission intensities of O（3p^5P → 3s^5S2^0.）,Hα（3P → 2s）,and N2^＋（B^2∑u^＋ →X^2∑g 0-0） increase and reach a maximum.Then,if the oxygen flow rate increases further,the emission intensities tend to decrease.However,the intensity of N2（C^3Πu → B^3Πg1-0） decreases monotonously with the increasing oxygen flow,which indicates that the electron density decreases with the increasing oxygen flow.By the tendencies of the relative intensities to N2（C^3Πu → B^3Πg 1-0）,the concentrations of the total produced O,H,and N2^＋ are shown to increase with the oxygen flow.Based on the reactions for the production of H and O without and with the addition of O2,the analytic solutions for H and O production are derived in accordance with the experimental results.

Postoperative reactive lymphadenitis: A potential cause of false-positive FDG PET/CT

A wide variety of surgical related uptake has been reported on F18-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography(FDG PET/CT) scan, most of which can be differentiated from neoplastic process based on the pattern of FDG uptake and/or anatomic appearance on the integrated CT in image interpretation. A more potential problem we may be aware is postoperative reactive lymphadenitis, which may mimic regional nodal metastases on FDG PET/CT. This review presents five case examples demonstrating that postoperative reactive lymphadenitis could be a false-positive source for regional nodal metastasis on FDG PET/CT. Surgical oncologists and radiologists should be aware of reactive lymphadenitis in interpreting postoperative restaging FDG PET/CT scan when FDG avid lymphadenopathy is only seen in the lymphatic draining location from surgical site.

大断面隧道瓦斯涌出位置对瓦斯分布的影响规律

大断面瓦斯隧道掌子面上不同的涌出位置对隧道内的瓦斯扩散分布规律影响较大。基于何家坡大断面隧道穿越一定交角煤层的工程背景,采用计算流体动力学软件Fluent模拟了5个不同涌出位置的瓦斯在隧道内的扩散分布规律。研究结果表明:大断面隧道掌子面可划分为3个主要的瓦斯涌出区域,即风筒对侧左下部分(区域Ⅰ)、靠近风筒侧右上部分(区域Ⅲ)和中间部分(区域Ⅱ);瓦斯自掌子面涌出后向洞口扩散的过程依次可以概括为瓦斯聚集、瓦斯扩散与瓦斯稳定分布3个阶段;区域Ⅰ、Ⅱ与Ⅲ涌出的瓦斯分别在0.4H、0.8H与1.3H范围内聚集,并分别在1.2H、1.4H与1.9H范围内扩散,最终分别在1.2H、1.4H与1.9H范围以外稳定分布于拱顶稍偏向风筒对侧,其中,H为隧道的高度。在此基础上,对隧道内瓦斯监测传感器的布局提出了优化方案,可为瓦斯隧道施工中的瓦斯监测及传感器布置提供一定的理论借鉴。

可水声定位的水下弹载测试系统设计

为了获取水下弹体发射全过程的多通道飞行姿态数据,并且针对水下弹体发射入水后难以搜寻的问题,设计了一种可水声定位的水下弹载测试系统。采用STM32F103C8T6作为主控芯片,控制系统多通道数据采集、存储与超声波脉冲信号的发出。设计了功率放大电路和阻抗匹配电路,提高了系统工作效率。经过测试,加载在换能器上的激励电压峰-峰值达134 V,可驱动换能器发出超声波。实验结果表明,采集系统可以连续高精度地采集弹体全过程飞行数据,在水下3.8 m可探测到目标,达到实际使用要求。

基于声发射的扫地机器人外壳碰撞点定位研究

扫地机器人领域的核心问题是定位问题,对扫地机器人行进过程中的碰撞位置进行有效定位是提高清扫效率的关键。声发射作为一种新型的无损检测技术,它的信号特性让其能在各种材料环境下进行定位实验。基于声发射技术的时差定位系统对于碰撞信号这种突发型信号有较好的捕捉定位能力,采用声发射时差法研究扫地机器人外壳在发生碰撞时的对应位置并进行定位误差分析。结果表明,声发射时差定位法能简单且快速地对碰撞点进行有效定位,利用声发射时差定位计算出的坐标与实际碰撞点坐标的误差最大值为8.45 mm,最小值为0.7 mm。研究结果可为实验研究和工程中声发射事件的精确定位提供重要参考。