Semi-implantable device based on multiplexed microfilament electrode cluster for continuous monitoring of physiological ions

Modern medicine is increasingly interested in advanced sensors to detect and analyze biochemical indicators.Ion sensors based on potentiometric methods are a promising platform for monitoring physiological ions in biological subjects.Current semi-implantable devices are mainly based on single-parameter detection.Miniaturized semi-implantable electrodes for multiparameter sensing have more restrictions on the electrode size due to biocompatibility considerations,but reducing the electrode surface area could potentially limit electrode sensitivity.This study developed a semi-implantable device system comprising a multiplexed microfilament electrode cluster(MMEC)and a printed circuit board for real-time monitoring of intra-tissue K^(+),Ca^(2+),and Na^(+)concentrations.The electrode surface area was less important for the potentiometric sensing mechanism,suggesting the feasibility of using a tiny fiber-like electrode for potentiometric sensing.The MMEC device exhibited a broad linear response(K^(+):2–32 mmol/L;Ca^(2+):0.5–4 mmol/L;Na^(+):10–160 mmol/L),high sensitivity(about 20–45 mV/decade),temporal stability(>2weeks),and good selectivity(>80%)for the above ions.In vitro detection and in vivo subcutaneous and brain experiment results showed that the MMEC system exhibits good multi-ion monitoring performance in several complex environments.This work provides a platform for the continuous real-time monitoring of ion fluctuations in different situations and has implications for developing smart sensors to monitor human health.

PARAMETERS OPTIMIZATION OF CONTINUOUS WAVELET TRANSFORM AND ITS APPLICATION IN ACOUSTIC EMISSION SIGNAL ANALYSIS OF ROLLING BEARING

Morlet wavelet is suitable to extract the impulse components of mechanical fault signals. And thus its continuous wavelet transform （CWT） has been successfully used in the field of fault diagnosis. The principle of scale selection in CWT is discussed. Based on genetic algorithm, an optimization strategy for the waveform parameters of the mother wavelet is proposed with wavelet entropy as the optimization target. Based on the optimized waveform parameters, the wavelet scalogram is used to analyze the simulated acoustic emission （AE） signal and real AE signal of rolling bearing. The results indicate that the proposed method is useful and efficient to improve the quality of CWT.

Real-Time Black Carbon Emissions from Light-Duty Passenger Vehicles Using a Portable Emissions Measurement System

Black carbon(BC)is considered the second largest anthropogenic climate forcer,but the radiative effects of BC are highly correlated with its combustion sources.On-road vehicles are an important source of anthropogenic BC.However,there are major uncertainties in the estimates of the BC emissions from on-road light-duty passenger vehicles(LDPVs),and results obtained with the portable emissions measurement system(PEMS)method are particularly lacking.We developed a PEMS platform and evaluated the on-road BC emissions from ten in-use LDPVs.We demonstrated that the BC emission factors(EFs)of gasoline direction injection(GDI)engine vehicles range from 1.10 to 1.56 mg.km^(-1),which are higher than the EFs of port fuel injection(PFI)engine vehicles(0.10–0.17 mg.km^(-1))by a factor of 11.The BC emissions during the cold-start phase contributed 2%–33%to the total emissions.A strong correlation(R^(2)=0.70)was observed between the relative BC EFs and average vehicle speed,indicating that traffic congestion alleviation could effectively mitigate BC emissions.Moreover,BC and particle number(PN)emissions were linearly correlated(R^(2)=0.90),and compared to PFI engine vehicles,the instantaneous PN-to-BC emission rates of GDI engine vehicles were less sensitive to vehicle specific power-to-velocity(VSPV)increase in all speed ranges.

Continuous Emission Spectrum Measurement for Electron Temperature Determination in Low-Temperature Collisional Plasmas

Continuous emission spectrum measurement is applied for the inconvenient diagnos- tics of low-temperature collisional plasmas. According to the physical mechanism of continuous emission, a simplified model is presented to analyze the spectrum in low temperature plasma. The validity of this model is discussed in a wide range of discharge parameters, including electron tem- perature and ionization degree. Through the simplified model, the continuous emission spectrum in a collisional argon internal inductively coupled plasma is experimentally measured to determine the electron temperature distribution for different gas pressures and radio-frequency powers. The inverse Abel transform is also applied for a better spatially resoluted results. Meanwhile, the result of the continuous emission spectrum measurement is compared to that of the electrostatic double probes, which indicates the effectiveness of this method.

Mechanical properties and damage characteristics of solidified body-coal combination in continuous driving and gangue backfilling

Recovery of the coal buried under buildings,railways and water bodies and the residual coal in irregularly arranged fully mechanized mining faces is a common engineering problem facing underground coal mining.In this study,a mining technology of continuous driving and gangue backfilling(CDGB)was proposed.The technology,which can not only alleviate ground subsidence and gangue discharge,but also release the above-mentioned coals,contributes to green and efficient sustainable development of mining.The stability of the system of the solidified body-reserved coal pillar combination(S-C combination)is crucial to the CDGB technology.Therefore,it is of great significance to explore the mechanical and damage characteristics of S-C combination in the synergistic bearing process.First,four sets of differentshaped S-C combination specimens were fabricated and a S-C combination bearing structure in CDGB was constructed to explore the differences in mechanical characteristics and damage modes of different-shaped S-C combination specimens during CDGB.Subsequently,their surface strain field evolutions and acoustic emission(AE)response characteristics in the load-bearing process were obtained with the aid of the digital image correlation technique and the AE signal monitoring system.Furthermore,a damage evolution model based on AE parameters and mechanical parameters was established to clarify the damage evolution law.The following results were obtained:(1)The free area of S-C combination can serve as a quantitative index to evaluate the stability of the overburden control system;(2)The concept of critical value k of the free area was first proposed.When the free area exceeds the critical value k(free area ratio greater than 1.13),the deformation resistance and the free area changes becomes negatively correlated;(3)As the free area expands,the failure of the S-C combination specimen evolves from tensile failure to shear failure.The distribution characteristics of the axial strain field also verified such a change in the failure mode;(4)When the free area expands,the peak AE count gradually changes from“double peaks”to“a single peak”.In this process,the expansion of free area shortens the time for accumulating and releasing energy during loading.Micro cracks generated in the specimen change from a phased steep growth to a continuous increase,and the process in which micro cracks develop,converge,intersect and connect to form macro cracks accelerates.The damage evolution law concluded based on AE parameters and mechanical parameters can well characterize the damage evolution process of S-C combination,providing certain reference for the study on the synergistic bearing of S-C combination during CDGB.

A Perspective of Laser Sampling for Inductively Coupled Plasma-Atomic Emission Spectro metry for Rock and Mineral Analysis

The development of laser sampling for optical emission spectrometry is reviewed . Advantages and limitations of pulsed laser sampling are compared with those of continuous laser sampling . A novel method of laser sampling of liquid samples for inductively coupled plasma -atomic emission spectrometry has been proposed , and its analytical performance investigated.Experimental results showed that,as a method of sample introduction , laser vaporization of liquid samples enjoyed certain advantages , e.g.,much higher sensitivity, much lower detection limit and reduced sample volume , over solution nebulization . A perspective of the application of laser sampling-inductively coupled plasma - actomic emission spectrometry for rock and mineral analysis is estimated as well.

Real-Time Modelling and Optimisation for Water and Energy Efficient Surface Irrigation

The viability and sustainability of crop production is currently threatened by increasing water scarcity. Water scarcity problems can be addressed through improved water productivity and the options usually presumed in this context are efficient water use and conversion of surface irrigation to pressurised systems. By replacing furrow irrigation with drip or centre pivot systems, the water efficiency can be improved by up to 30% to 45%. However, the installation and application of pumps and pipes, and the associated fuels needed for these alternatives increase energy consumption. A balance between the improvement in water use and the potential increase in energy consumption is required. When surface water is used, pressurised irrigation systems increase energy consumption substantially, by between 65% to 75%, and produce greenhouse gas emissions around 1.75 times higher than that of gravity based irrigation systems so their use should be carefully planned keeping in view adverse impact of carbon emissions on the environment and threat of increasing energy prices. With gravity-fed surface irrigation methods, the energy consumption is assumed to be negligible. This study has shown that a novel real-time infiltration model REIP has enabled implementation of real-time optimisation and gravity fed surface irrigation with real-time optimisation has potential to bring significant improvements in irrigation performance along with substantial water savings of 2.92 ML/ha which is equivalent to that given by pressurised systems. The real-time optimisation and control thus offers a modern, environment friendly and water efficient system with close to zero increase in energy consumption and minimal greenhouse gas emissions.

Calculation of Solidification Process of Continuous Cast Bar

In this paper,it presents the results of calculation of solidification process of copper continuous cast bar by cross section size 120 mm × 70 mm with application of Pro Cast 2010 software. The estimation of mould design effect on solidification process of continuos copper cast bar is completed at various speeds of casting.Profiles of liquid metal cavities and temperature allocations in the cast bar at various casting speeds are defined.The analysis of received liquid metal cavity profiles shows that a new mold construction allows significantly decrease of the length of the liquid metal cavity during continuous copper casting at HAZELETTcasting machine and the increase of maximum casting speed from 10 to 11 m / min. Adequacy of the results of copper continuous cast bar solidification process calculation is confirmed by the experimental data.

Influence of fluorescence time characteristics on the spatial resolution of CW-stimulated emission depletion microscopy

As one of the most important realizations of stimulated emission depletion （STED） microscopy, the continuous- wave （CW） STED system, constructed by using CW lasers as the excitation and STED beams, has been investigated and developed for nearly a decade. However, a theoretical model of the suppression factors in CW STED has not been well established. In this investigation, the factors that affect the spatial resolution of a CW STED system are theoretically and numerically studied. The full-width-at-half-maximum （FWHM） of a CW STED with a doughnut-shaped STED beam is also reanalyzed. It is found that the suppression function is dominated by the ratio of the local STED and excitation beam intensities. In addition, the FWHM is highly sensitive to both the fluorescence rate （inverse of fluoresce lifetime） and the quenching rate, but insensitive to the rate of vibrational relaxation. For comparison, the suppression function in picosecond STED is only determined by the distribution of the STED beam intensity scaled with the saturation intensity. Our model is highly consistent with published experimental data for evaluating the spatial resolution. This investigation is important in guiding the development of new CW STED systems.

高铁服务供给对碳减排的影响——基于空间溢出效应

交通基础设施建设深刻影响环境质量,却鲜有研究关注高铁发展对于碳排放的影响。本文基于直接环境效应和间接经济效应双重路径,理论剖析高铁服务供给实现碳减排的内在机制,进而将空间计量模型与连续型双重差分相结合,基于高铁服务频次数据实证考察高铁服务供给如何影响城市碳排放,及其在空间维度的溢出效应。研究发现,高铁服务供给有助于减少本地碳排放,同时具有碳减排空间溢出效应;时间维度上,高铁服务供给的本地减排效应立竿见影且渐趋强化,而对于周边地区碳排放的影响则存在明显的时滞特征;机制检验表明高铁服务供给能够基于交通工具替代发挥空间减排效应;高铁服务供给的碳减排效应在资源禀赋维度和地理位置维度表现出异质特征。本文进一步丰富了高铁与碳减排研究内容,既拓展了碳减排的交通基础设施建设路径,亦为高铁发展的环境效应提供了有力佐证。

国内固定排放源二氧化碳排放连续监测应用现状和问题初探

碳监测是我国“十四五”生态环境监测体系的重要组成部分,也是支撑我国“双碳”目标落地的重要技术方向。随着碳监测技术的发展成熟,固定排放源二氧化碳排放连续监测技术逐渐具备了推广的条件。本文总结了国内外二氧化碳排放连续监测技术的发展和应用现状,结合当前我国相关政策要求和标准发布情况,分析了当前我国二氧化碳排放连续监测中存在的问题,提出了加强企业碳监测管理的相关建议。

聚合物水泥防水涂料用苯丙乳液的研制及其各因素影响研究

通过预乳化半连续种子乳液聚合法自制了JS防水涂料专用苯丙乳液,并由此制备了聚合物水泥防水涂料。研究了乳化剂用量及其分配对苯丙乳液粒径及其吸水率的影响,同时通过尝试不同的方法降低乳液残留单体减少VOC排放。在自制苯丙乳液的基础上探究不同液粉比对聚合物水泥防水涂料拉伸性能的影响,通过添加一些不同的助剂来提升聚合物水泥防水涂料的综合性能。

非分散红外CEMS在超低排放气态污染物监测中的应用探讨

现有非分散红外CEMS在使用过程中,由于烟气中的水分和CH_(4)等因素的交叉干扰,会造成SO_(2)和NO的监测结果出现偏差,难以满足超低排放的监测要求。分析了非分散红外CEMS工作时出现冷凝水的原因,以及烟气中水分和CH4对SO2红外吸收波段干扰特点,提出了解决样气管中冷凝水和降低烟气中含水率的方法,并给出了消除CH4对SO2测量数据干扰的方法和CEMS的优化方案,实际应用表明:改进后的CEMS对水汽及烟气中其他组分具有极强的抗干扰性,为超低排放气态污染物监测提供了准确的监测方法。

金属材料表面发射率测量装置的设计与应用

【目的】针对测量管壳式热交换器的管束表面发射率精度低、成本高的问题,设计了测量金属材料表面发射率的装置,提出测量金属材料表面发射率的方法。【方法】该装置结合温度平滑算法后,可以对设备全工作状态时被测材料表面发射率进行测量。【结果】使用该方法对块状钢材样品在200~500℃温度区间内进行测试,结果表明,标准算法下的温度仍然存在波动,且会造成发射率的振荡。而采用优化算法对于噪声和发射率有明显的平滑作用,即使面对外部环境扰动也有足够的抗性。【结论】研究结果可为相关设备炉内温度的精确测量提供参考。

锅炉连排污水回收效益探究

中信锦州金属股份有限公司自备电厂三台75 t/h立式排渣旋风炉连排污水从汽包排出时,带有较高焓值且水质较好,通过连排扩容器回收一部分蒸汽后,污水温度、压力仍然较高,如果直接排至总污水,会造成一部分能源浪费,同时也使热电厂总污水排量增加。本文主要探讨分析热电厂锅炉连排污水回收方式和效益,以实现节能、减排、降成本的目标。

CEMS在液化天然气接收站中的设计探讨

针对液化天然气接收站中浸没燃烧式汽化器(SCV)燃烧烟气中NO_(x)的特点,设计了烟气排放连续监测系统(CEMS),详细介绍了CEMS的组成,采样方式、分析仪的选取,烟气参数监测单元和数据采集与处理单元的设置等,对CEMS的安装和后期维护提出了相应的建议方案。该系统设计方案不但可以监控烟气排放是否达标,还可以监测烟气中的CO浓度来反映SCV低氮燃烧器的燃尽效率,有效降低生产维护费用。

防爆连续固液分离洗涤工艺探讨

针对易燃易爆、有毒有害料浆采用传统固液分离工艺,存在设备腐蚀、不利于安全生产、开车率低和维护困难等问题,采用单台防爆翻盘真空过滤机,并优化固液分离洗涤流程,即可实现封闭式连续固液分离,多次洗涤的工艺要求,且达到安全生产、三无排放、节能减排的目的。

燃气轮机烟气排放超标原因分析及设备选型建议

烟气排放连续监测系统作为火力发电厂固定污染源排放监测的重要环保设施,其监测数据关系到火电厂的污染源排放是否符合国家环保要求。由于烟气排放连续监测系统设备选型问题,某公司燃气轮机机组污染源监测数据出现异常,甚至超出排放标准。结合现场实际情况,分析该公司烟气排放连续监测系统设备的工作原理,对氮氧化物(NO_(x))、二氧化硫(SO_(2))以及烟尘排放浓度超标原因进行了具体陈述,提出了设备选型建议。

利用DCS系统网络实现炼化企业固定污染源在线监测数据上传

针对炼化企业污染排放特点及环保监管需求,本文重点介绍如何利用DCS系统网络实现固定污染源在线监测数据上传,并对在线监测在实际运用中平台数据显示离线等故障现象进行解析。

Effects of continuously regenerating diesel particulate filters on regulated emissions and number-size distribution of particles emitted from a diesel engine

The effects of continuously regenerating diesel particulate filter （CRDPF） systems on regulated gaseous emissions, and number-size distribution and mass of particles emanated from a diesel engine have been investigated in this study. Two CRDPF units （CRDPF-1 and CRDPF-2） with different specifications were separately retrofitted to the engine running with European steady-state cycle （ESC）. An electrical low pressure impactor （ELPI） was used for particle number-size distribution measurement and mass estimation. The conversion/reduction rate （RcR） of hydrocarbons （HC） and carbon monoxide （CO） across CRDPF-1 was 83% and 96.3%, respectively. Similarly, the RCR of HC and CO and across CRDPF-2 was 91.8% and 99.1%, respectively. The number concentration of particles and their concentration peaks; nuclei mode, accumulation mode and total particles; and particle mass were highly reduced with the CRDPF units. The nuclei mode particles at downstream of CRDPF-1 and CRDPF-2 decreased by 99.9% to 100% and 97.8% to 99.8% respectively; and the particle mass reduced by 73% to 92.2% and 35.3% to 72.4%, respectively, depending on the engine conditions. In addition, nuclei mode particles increased with the increasing of engine speed due to the heterogeneous nucleation initiated by the higher exhaust temperature, while accumulation mode particles were higher at higher loads due to the decrease in the air-to-fuel ratio （A/F） at higher loads.