Amino-functionalized UiO-66-doped mixed matrix membranes with high permeation performance and fouling resistance

For the reduction of bovine serum proteins from wastewater,a novel mixed matrix membrane was prepared by functionalizing the substrate material polyaryletherketone(PAEK),followed by carboxyl groups(C-SPAEKS),and then adding amino-functionalized UiO-66-NH_(2)(Am-UiO-66-NH_(2)).Aminofunctionalization of UiO-66 was accomplished by melamine,followed by an amidation reaction to immobilize Am-UiO-66-NH_(2),which was immobilized on the surface of the membrane as well as in the pore channels,which enhanced the hydrophilicity of the membrane surface while increasing the negative potential of the membrane surface.This nanoparticle-loaded ultrafiltration membrane has good permeation performance,with a pure water flux of up to 482.3 L·m^(-2)·h^(-1) for C-SPAEKS/AmUiO-66-NH_(2) and a retention rate of up to 98.7%for bovine serum albumin(BSA)-contaminated solutions.Meanwhile,after several hydrophilic modifications,the flux recovery of BSA contaminants by this series of membranes increased from 56.2%to 80.55%of pure membranes.The results of ultra-filtration flux time tests performed at room temperature showed that the series of ultrafiltration membranes remained relatively stable over a test time of 300 min.Thus,the newly developed mixed matrix membrane showed potential for high efficiency and stability in wastewater treatment containing bovine serum proteins.

Impact Analysis of EV Charging with Mixed Control Strategy

EVs （electric vehicles） have been widely accepted as a promising solution for reducing oil consumption, air pollution and greenhouse gas emission. The number of EVs is growing very fast over the years. However, the high adoption of EVs will impose a burden on the power system, especially for neighborhood level network. In this paper, we propose a mixed control framework for EV charging scheduling to mitigate its impact on the power network. A metric for modeling customer＇s satisfaction is also proposed to compare the user satisfaction for different algorithms. The impacts of the proposed algorithms on EV charging cost, EV penetration and peak power reduction are evaluated with real data for a neighborhood level network. The simulation results demonstrate the effectiveness of the proposed algorithms.

Partition Equilibrium on the Interface Between a Charged Membrane and a Mixed Electrolyte Aqueous Solution

Ionic partition equilibrium on a charged membrane immersed in a mixed electrolyte solution was systematically investigated and several models were established for the determination of partition coefficients. On the basis of theoretical models, the effects of the concentration ratio λ of the fixed group(charged density) to reference electrolyte, the concentration ratio η between the two electrolytes existing in the solution and the valence of the electrolyte ions on the partition equilibrium in a positively charged membrane were analyzed and simulated within the chosen parameters in detail. The obtainable results can also be applicable to a sytem of mixed electrolytes contacting with a negatively charged membrane. The theoretical calculations were confirmed with the experimental data of model mixed electrolytes, NaCl+HCl and CaCl 2+NaCl partitioned in the system of self made negatively charged membrane sulphonated poly(phenylene oxide)(SPPO) with different charge densities.

Discharge mode and particle transport in radio frequency capacitively coupled Ar/O_(2) plasma discharges

Simulations are conducted on capacitively coupled Ar/O_(2)mixed gas discharges employing a one-dimensional fluid coupled with an electron Monte Carlo(MC)model.The research explores the impact of different O_(2)ratio and pressures on the discharge characteristics of Ar/O_(2)plasma.At a fixed Ar/O_(2)gas ratio,with the increasing pressure,higher ion densities,as well as a slight increase in electron density in the bulk region can be observed.The discharge remains dominated by the drift-ambipolar(DA)mode,and the flux of O(3P)at the electrode increases with the increasing pressure due to higher background gas density,while the fluxes of O(1D)and Ardecrease due to the pronounced loss rate.With the increasing proportion of O_(2),a change in the dominant discharge mode from a mode to DA mode can be detected,and the O_(2)-associated charged particle densities are significantly increased.However,Ar+density shows a trend of increasing and then decreasing,while for neutral fluxes at the electrode,Arflux decreases,and O(3P)flux increases with the reduced Ar gas proportion,while trends in O(1D)flux show slight differences.The evolution of the densities of the charged particle and the neutral fluxes under different discharge parameters are discussed in detail using the ionization characteristics as well as the transport properties.Hopefully,more comprehensive understanding of Ar/O_(2)discharge characteristics in this work will provide a valuable reference for the industry.

Experimental Investigation of the Effect of Mixed Additives on Homogeneous Charge Compression Ignition Combustion

The experimental investigation of homogeneous charge compression ignition (HCCI) process is carried out on a 4-cylinder diesel engine. One of the cylinders is modified for HCCI combustion with mixed additives. The influence of mixed additives on the HCCI combustion process is investigated. The experimental results indicate that the mixed additives are better than the single additives for HCCI fuel, causing ignition and heat release to be advanced and the peak of heat release rate to increase under the condition of different engine speeds and steady HCCI combustion. Moreover, with the increase in engine speed, the influence of mixed additives on HCCI combustion is more obvious. In addition, the mixed additives are beneficial to improve HCCI engine misfire at a high engine speed and make the engine operate stable.

Recent advances in Pb-Sn mixed perovskite solar cells

Organic-inorganic hybrid lead-tin perovskite solar cells(Pb-Sn PSCs)have attracted much attention because of their advantages of low toxicity,variable bandgap,and feasibility for all-perovskite tandem solar cells,and the current power conversion efficiency(PCE)has exceeded 23%.However,due to the rambunctious crystallization process,easily oxidized Sn(Ⅱ)and inadequate energy level arrangement,there are many defects in perovskite films resulting in serious carrier recombination,which makes PCE still lag Pb-based PSCs.The quality of perovskite films is an important factor affecting the overall device performance.The selection and optimization of transport layers not only determines the interface energy level arrangement but also affects the carrier transport.In this paper,the research progress in improving performance of Pb-Sn PSCs in recent years is reviewed from aspects of perovskite layer and transport layers.The profound understanding of different promotion methods is summarized as well.These results have certain guiding significance for the future development and commercial application of Pb-Sn PSCs.

Different Mixing Scenerio of Quasi-Degenerate Neutrino with Charged Lepton Correction

Theoretically, in order to achieve non-zero θ13 a little deviation from Tribimaximal Mixing (TBM) pattern is needed, especially on θ13 without perturbing the atmospheric and solar mixing angles. In this work we computed the neutrino mixing angles by disturbing the θ13 as well as θ12 in Bimaximal (BM) and Hexagonal mixing (HM) using non-diagonal charged lepton mass. Considering the standard form of mass texture which satisfies TBM we have shown the quasi-degenerate nature of neutrino. This quasi degenerate type of mass matrix for BM and HM is then used to calculate the deviated mixing pattern which are consistent with recent neutrino oscillation data.

基于混合储能荷电状态的光伏直流微网系统能量分配策略

针对混合储能系统在平抑光伏波动以及负荷投切时荷电状态(SOC)易越限问题,提出一种基于混合储能SOC的多模式协调控制策略。在传统低通滤波功率分配的基础上,提出一种基于超级电容荷电状态的动态功率修正策略,使超级电容出力后SOC向安全状态恢复;同时,为避免蓄电池频繁切换充放电状态,在其响应环节加入优化后的延时控制。此外,根据光伏出力情况、混合储能SOC,设计出满足直流微网系统动态平衡的六种运行模式,实时调节各储能单元出力情况。在MATLAB/Simulink中搭建了光伏直流微网混合储能系统仿真模型,仿真结果表明所提策略在各工况下均能稳定运行,有效延长了储能介质使用寿命。

含循环换电负荷及充电站的微电网多目标优化调度

电动换电重卡由于具有充电功率高、周期性强的循环换电负荷特性,一旦短时大量接入微电网中,将带来经济性和安全性的挑战。首先讨论电动汽车充电、循环换电负荷的不同特性,建立含循环换电负荷及充电站的微电网模型;提出一种综合考虑微电网经济性及联络线功率波动性的多目标调度优化方法;采用线性加权方法将多目标问题转化为单目标问题;最后利用CPLEX工具对仿真算例进行求解,仿真算例表明,所提优化方案可有效求解综合考虑不同权重下微电网净利润、联络线交换功率及换电站内电池最优调度问题,能在尽可能减小微电网与上级电网交换功率波动性的同时,使得微电网获得最大净利润。

基于改进麻雀搜索的雷暴云电荷反演方法

为解决雷暴云电荷反演方法精度较差、现有电荷反演模型受多站组网观测造成的环境误差影响等问题。在假设雷暴云层等厚模型的基础上,推导雷暴云电荷反演所需非线性方程组,建立基于三维大气电场的雷暴云电荷反演模型,通过正弦混沌映射函数优化麻雀搜索算法(SSA)种群初始化方式,提高种群分布的非线性,使用莱维飞行(Levy)函数和反向学习策略优化算法发现者的位置更新方式,提出一种基于改进麻雀搜索算法(ISSA)的雷暴云电荷反演方法。利用三维大气电场仪对地面电场数据进行观测并分析电场特征,使用混合策略改进的SSA算法反演雷暴云充电模型参数。实验结果表明,使用三维大气电场仪观测所得数据进行反演,能够有效消除多站组网观测造成的误差,对比SSA,改进后的ISSA算法反演所得雷暴云两秒相邻电荷量的偏差率均在1%左右,适应度值最低达到5.38,能较为精确的反演雷暴云电荷参数,为研究其充放电过程提供一定参考。

我国现场混装技术发展的现状与展望

现场混装技术是集原料运输、现场混制、炮孔装药等多工序于一体,并融炸药技术、爆破技术、装备技术等多门类于一身的新技术,具有本质安全、优质高效、绿色环保等优点,代表着国际上工业炸药技术与工程爆破技术的未来发展方向。首先总体回顾了国内外现场混装技术的发展沿革,进而指出我国现场混装技术发展现状,剖析了制约我国现场混装技术应用推广的原因,最后展望了我国现场混装技术的发展趋势,并提出促进我国现场混装技术发展的6条建议,对培育新质生产力有较强指导意义。

高原隧道现场混装炸药爆破试验效果分析

针对隧道传统包装炸药爆破炮孔数量多、作业人员密集等问题,基于现场混装炸药机械化装药及连续耦合装药结构优势,在高原隧道进行了60次现场混装炸药爆破试验,总结了不同人数的装药作业工效,开展了隧道孔网参数优化及周边孔光面爆破效果改进试验,将原包装爆破孔数151个优化至124个,同时周边孔间距由原45 cm逐步调整为60 cm,对比光面爆破效果。结果表明:相比传统包装炸药爆破,现场混装炸药爆破可提高人均作业工效40%以上,降低劳动强度约90%,显著减少危险作业人员,同时节省钻孔数量和起爆器材使用量15%以上及改善了爆破效果,提高了钻孔与挖装效率,提高循环进尺3%以上,有利于加快隧道施工进度。

试论焦丁在高炉高比例球团矿治炼中的作用

简要分析了高炉高比例球团矿治炼的难点,认为可通过矿焦混装技术来改善冶炼效果,并可适当提高焦丁人炉比例,将焦丁粒度下限调整为6~8mm。重点分析了焦丁在高炉冶炼中的作用,主要包括:①矿焦混装可限制球团矿滚动,稳定料面形状,焦丁比大于60kg/t时,焦丁对球团矿滚动的限制效果明显变强;②降低焦丁平均粒度,与矿石粒度相近,改善块状带透气性;③由于焦丁的存在,铁橄榄石相的生成量受到抑制,且在1050℃下能够被碳直接还原,避免了球团矿表面形成致密的金属铁壳,其还原性能得到改善;④加大焦丁量能进一步改善炉料的软化和熔滴性能,有利于缓解高球比冶炼时软熔带透气性差的问题。

一种细粒度的复式收费车道交通仿真模型及车道设置标准研究

为研究收费类型、收费亭间距、收费亭数量等条件的设置情况对复式收费车道通行能力的影响,构建了一种细粒度的复式收费车道交通仿真模型,经验证该模型的通行能力的模拟准确度达到约96%。基于该模型,对不同设置条件的通行能力仿真分析。结果表明:车流中ETC车辆的流量占比与混合复式收费车道的通行能力提升幅度呈负相关关系;车流中大型车占比越大则因收费亭间距不足带来的通行能力折减幅度越大,对应10%~50%的大型车流量占比范围,双亭、三亭复式收费车道在收费亭间距不足时通行能力折减幅度达到2.53%~11.63%;复式收费车道通行能力提升的幅度随收费亭数量增加而减小,且对于服务时间长的收费车道,增加复式收费亭可带来更加显著的通行能力提升效果。

稀盐酸对铸造镁合金回炉料混料判定的影响

在铸造镁合金熔炼过程中添加回炉料时,用稀盐酸滴在回炉料锯切的光洁面上,可根据合金表面与稀盐酸反应时不同的反应现象区分铸造镁合金材料牌号。有效识别回炉料成分,防止发生混料、造成成本浪费。

BCJ-4I型混装炸药车在石碌铁矿中深孔爆破的应用

针对石碌铁矿上向中深孔人工装药过程中,存在安全隐患大、工人劳动强度大、返粉率高、作业环境恶劣、作业效率低等缺点,引进先进的混装炸药车,应用专用乳胶基质及敏化剂溶液、闭环比例控制、无线遥控寻孔和自动送、退管等关键技术,实现装药作业机械化、自动化、智能化,降低了炸药成本,改善了爆破效果,同时减小了工人劳动强度,提高了作业安全性。

用超声/电声谱监测锂电池正极浆料的合浆及包覆质量

在前期工作的基础上,利用超声/电声学方法对锂电池浆料合浆工艺的质量控制参数进行了探索,对不同来源和不同批次的N-甲基吡咯烷酮(NMP)体系磷酸铁锂电池(LFP)浆料进行了粒度、zeta电位及其微观电学参数的测定。结果显示,对于分散较好的合格样品,浆料的粒度、zeta电位、表面电荷密度可基本重现;而对于原料粒度检测不合格的样品,不仅浆料粒度分布呈现双峰,zeta电位有较大的波动,且表面电荷密度降低,批次间不稳定。研究表明,超声法直接测定锂电池合浆过程中的原浓浆料粒度直观有效,对于工艺质控非常重要;在合浆过程中,因导电添加剂团聚的存在,很难均匀包覆在LFP颗粒上。因此,zeta电位和双电层厚度可以成为导电剂是否分散和包覆均匀的关键质量控制参数。

含EV充换储一体站的交直流混合配电网优化运行

为了促进电动汽车产业的进一步发展,构建了计及充换储一体站(CSSIS)的交直流混合配电网多时间尺度优化调度模型。首先,基于快充用户行为和城市交通特征分别构建了充电站模型和换电站模型,再结合储能电站模型完成了CSSIS建模。然后,在计及CSSIS、微型燃气轮机和可再生新能源等接入的交直流混合配电网中,构建了优化调度模型。为降低预测精度误差的影响,采用了多时间尺度协调优化策略处理。该模型属于非线性非凸混合整数规划问题,采用线性化和二阶锥松弛方法将其转化为可用商业求解器处理的混合整数二阶锥凸优化模型。最后,以改进的IEEE 50节点系统为例进行了仿真分析,仿真结果验证了交直流混合配电网形式具有更强的适应性,以及CSSIS具有高效参与电网优化运行的能力。

Defect-rich Mg-Al MMOs supported TEPA with enhanced charge transfer for highly efficient and stable direct air capture

Due to the advantages of low energy consumption and high CO_(2) selectivity, the development of solid amine-based materials has been regarded as a hot research topic in the field of DAC for the past decades.The adsorption capacity and stability over multiple cycles have been the top priorities for evaluation of practical application value. Herein, we synthesized a novel DAC material by loading TEPA onto defect-rich Mg_(0.55)Al-O MMOs with enhanced charge transfer effect. The optimal Mg_(0.55)Al-O-TEPA67% demonstrates the highest CO_(2)uptake of(3.0 mmol g^(-1)) and excellent regenerability, maintaining ~90% of the initial adsorption amount after 80 adsorption/desorption cycles. The in situ DRIFTS experiments suggested the formation of bicarbonate species under wet conditions. DFT calculations indicated that the stronger bonding between Mg_(0.55)Al-O support and solid amine was caused by the abundance of oxygen defects on MMOs confirmed by XPS and ESR, which favors the charge transfer between the support and amine,resulting in intense interaction and excellent regenerability. This work for the first time conducted comprehensive and systematic investigation on the stabilization mechanism for MMOs supported solid amine adsorbents with highest uptake and superior cyclic stability in depth, which is different from the most popular SiO_(2)-support, thus providing facile strategy and comprehensive theoretical mechanism support for future research about DAC materials.

Charge transfer and orbital reconstruction of non‐noble transition metal single‐atoms anchored on Ti_(2)CT_(x)‐MXenes for highly selective CO_(2) electrochemical reduction

Inspired by MXene nanosheets and their regulation of surface functional groups,a series of Ti_(2)C‐based single‐atom electrocatalysts(TM@Ti_(2)CT_(x),TM=V,Cr,Mn,Fe,Co,and Ni)with two dif‐ferent functional groups(T=–O and–S)was designed.The CO_(2)RR catalytic performance was stud‐ied using well‐defined ab initio calculations.Our results show that the CO_(2) molecule can be more readily activated on TM@Ti_(2)CO_(2) than the TM@Ti_(2)CS_(2) surface.Bader charge analysis reveals that the Ti_(2)CO_(2) substrate is involved in the adsorption reaction,and enough electrons are injected into the 2π*u orbital of CO_(2),leading to a V‐shaped CO_(2) molecular configuration and partial negative charge distribution.The V‐shaped CO_(2) further reduces the difficulty of the first hydrogenation reac‐tion step.The calculatedΔG of the first hydrogenation reaction on TM@Ti_(2)CO_(2) was significantly lower than that of the TM@Ti_(2)CS_(2) counterpart.However,the subsequent CO_(2) reduction pathways show that the UL of the potential determining step on TM@Ti_(2)CS_(2) is smaller than that of TM@Ti_(2)CO_(2).Combining the advantages of both TM@Ti_(2)CS_(2) and TM@Ti_(2)CO_(2),we designed a mixed functional group surface with–O and–S to anchor TM atoms.The results show that Cr atoms an‐chored on the surface of mixed functional groups exhibit high catalytic activity for the selective production of CH4.This study opens an exciting new avenue for the rational design of highly selec‐tive MXene‐based single‐atom CO_(2)RR electrocatalysts.