Complexation Between Borate ion and Hydroxyl Groups of Phenol-Formaldehyde Resol Resin

The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexation can proceed completely and rapidly at room temperature. Borate ion attacks phenol hydroxyl groups and adjacent position hydroxymethyl groups on the phenol ring of the resin, and forms the coordinate bond between boron atom in borate ion and oxygen atom in the hydroxyl groups. The complexation is a quantitative reaction. The complex is a six member ring containing two oxygens and one boron. The complexation can release hydrogen ions resulting in the decreasing pH in the resin solution.

Synthesis and Adsorption Properties of Polystyrene-supported Chelating Resins Containing Heterocyclic Functional Groups

A series of new chelating resins with incorporating heterocyclic functional groups： pyridine, thiadizole, benzothizole into macroporous chloromethylated polystyrene were synthesized via hydrophilic spacer arm of polyethylene glycol containing sulfur. These chelating resins were found to show high adsorption capacities for Ag^＋, Hg^2＋, Au^3＋ and Pd^2＋, and the presence of spacer arm can enhance adsorption ability due to increase the hydrophilicity of the chelating resins.

Synthesis and Adsorption Properties of Chelating Resins Containing Sulfoxide and Heterocyclic Functional Groups

Several of new chelating resins containing sulfoxide and heterocyclic functional groups （3-aminopyridine and 2-mercaptobenzothiazole） based on macroporous chloromethylated polystyrene were synthesized and characterized by elemental analysis and infrared spectra. Their adsorption capacities towards Zn^2＋, Cu^2＋, Pb^2＋, Hg^2＋ and Ag^＋ at pH 3.0 and 6.0 were investigated in detail. It was found that the adsorption capacities of the resins containing bis[（3-pyridylaminoethyl）sulfoxide or （2-benzothiazolylthioethyl）sulfoxide for the above ions were higher than that on ones containing single above-mentioned groups.

Analysis of Functional Group of Alkaline Phosphatase from DFRKN-1

To further understand characters of alkaline phosphatase and provide reference for in-depth study of the mechanism of NFRKN-1 invading into knot nem-atode and its development and utilization, the effects of metal ions, organic reagents and chemical modifier on activity of alkaline phosphatase from DFRKN-1 were analyzed in the paper. The results showed that Mg^2＋ , Ba^2＋ and K^＋ under certain concentrations activated enzyme significantly and Zn^2＋ could inhibit enzyme activ-ity. Methanol, ethanol and ethylene glycol inhibited enzyme activity in similar degrees. Histidine residue and Lysine residue are essential groups of alkaline pbos-phatase; sulflaydryl of cysteine was not an essential group, but disulfide bond played an important role in maintaining the active conformation of alkaline phospha-tase.

基于PSO-CNN的储能锂离子电池组荷电状态评估

将卷积神经网络(convolutional neural network,CNN)的权值和阈值作为粒子群算法(particle swarm optimization,PSO)的粒子,将CNN的损失函数作为PSO的适应度函数,从而构建PSO-CNN算法对储能锂离子电池组的荷电状态(state of charge,SOC)进行预测。以储能系统现场采集的充放电数据为样本,分别采用本文算法、基于PSO优化的支持向量机(support vector machine,SVM)、CNN进行训练,并在完整充放电数据集上对比3种算法的预测效果。结果表明本文算法收敛性好、预测精度高。最后采用另一储能现场的数据验证本文算法具有良好的鲁棒性,可以广泛适用于储能系统锂离子电池组SOC的在线预测。

Interface engineering via molecules/ions/groups for electrocatalytic water splitting

The electrochemical water splitting to produce hydrogen converts electric energy into clean hydrogen energy,which is a groundbreaking concept of energy optimization.To achieve high efficiency,numerous strategies have been developed to enhance the performance of electrocatalysts.Among these,interface engineering with molecules/ions/groups,serves as a versatile approach for optimizing the performance of electrocatalysts in water splitting.On the basis of numerous achievements in high-performance electrocatalysts engineered through molecules/ions/groups at interface,a comprehensive understanding of these advancements is crucial for guiding future progress.Herein,after providing a concise overview of the background,the interface engineering via molecules/ions/groups for electrocatalytic water splitting is demonstrated from three perspectives.Firstly,the engineering of electronic state of electrocatalysts by molecules/ions/groups at interface to reduce the Gibbs free energy of the corresponding reactions.Secondly,the modification of local microenvironment surrounding electrocatalysts via molecules/ions/groups at interface to enhance the transfer of reactants and products.Thirdly,the protection of electrocatalysts with molecule/ion/group fences improves their durability,including protecting active sites from leaching and defending them against harmful species.The fundamental principles of these three aspects are outlined for each,along with pertinent comments.Finally,several research directions and challenges are proposed.

低浓度轻稀土离子的选择性萃取分离

本文研究了采用1,7-二氮杂15冠5醚(2N15C5)从多离子共存的复杂硫酸盐体系中选择性萃取分离轻稀土离子的过程。结果表明:水相中的高浓度杂质离子主要通过诱导稀土硫酸钠盐沉淀的生成来影响复杂硫酸盐体系的稳定性,从而降低2N15C5对轻稀土离子的选择性萃取分配比。在水相pH<2.0、[SO_(4)^(2-)]/Σ[RE^(3+)]<10、相比R_(O/A)=2∶1、混相时间10 min的情况下,轻稀土离子组与重稀土离子组的单级萃取分离系数可达23.0023,经5级逆流萃取处理后,对应的累积萃取分离系数可达36.7016。该分组萃取分离法可从离子吸附型稀土矿原地浸出尾液中选择性萃取分离低浓度轻稀土离子,负载有机相经稀盐酸洗杂、乙二胺四乙酸溶液反萃处理后可得到轻稀土富集液,轻稀土离子的综合收率为83.98%。

共存离子对粘质沙雷氏菌吸附钇的影响

本研究以粘质沙雷氏菌为吸附剂,以水溶液中的钇离子对吸附对象,研究了钇溶液中存在铝、铁、锌和镁离子对粘质沙雷氏菌吸附钇的影响。结果表明,铝离子严重抑制粘质沙雷氏菌对钇的吸附,铁、锌和镁离子对吸附的抑制较弱,多种离子共存对粘质沙雷氏菌吸附钇的抑制程度依次为:锌+铁+铝>铝+铁>锌+铁>锌+铝。共存离子对粘质沙雷氏菌吸附钇都有抑制作用,这可能是由于它们和钇离子竞争吸附在粘质沙雷氏菌表面吸附,吸附的抑制程度不同应该是因为粘质沙雷氏菌吸附这些共存离子的活性基团不同。红外光谱分析结果证实了粘质沙雷氏菌的羧基、氨基和羟基是吸附铁、镁和锌离子的主要官能团,而羧基和羟基是吸附铝离子的主要官能团。

生物炭的化学改性及其对重金属离子的吸附性能

生物炭的化学改性中,表面修饰和负载可增加化学吸附位点来实现对重金属离子的吸附,被认为是有效提高生物炭吸附性能的可行之法。本文面向化学改性,将上述两类改性方法细分为六种,阐述和讨论了各种改性方法的原理及优缺点。最后,对化学改性生物炭未来发展趋势进行了展望。

A study of phosphate adsorption by different temperature treated hydrous cerium oxides

An alkaline precipitation method was introduced to produce hydrous cerium oxides.The prepared powder was characterized by Brunauer-Emmett-Teller（BET） nitrogen adsorption-desorption,X-ray diffraction（XRD）,Fourier transform infrared（FTIR） spectrometry,and thermal gravimetry（TG） approaches.The adsorbent has a chemical formula of CeO2·nH2O（n 2） and a cubic fluorite-type structure after high temperature treatment.Adsorption capacity of different temperature treated hydrous cerium oxides does not directly correlate with BET specific surface area.Phosphate adsorption isotherms follow the Langmuir equation below the treatment temperature of 800°C.Phosphate adsorption causes no change on the structure of a hydrous cerium oxides,and no signs of CePO4 precipitates are found.The ion-exchanging structure of hydrous cerium oxide plays a fundamental role in phosphate adsorption.The structure is highly temperature resistant and forms adsorption sites which adsorb both water and some anions.Complete loss of adsorption ability cannot be achieved unless the treatment temperature is higher than 1200°C.Mechanism study shows that the adsorption of phosphates is mainly an anion-exchange process.

双氰胺涂层修饰二氧化锰复合材料的构建及其储锌性能提升机制

二氧化锰(MnO_(2))由于具有高理论容量、高工作电压和环境友好等优点被认为是水系锌离子电池中最有应用潜力的正极材料之一。然而,由于不稳定的晶体结构及放电时锰溶解等导致其严重的容量衰减。基于此,本论文采用双氰胺(DCDA)对α-MnO_(2)进行表面包覆,并研究了DCDA包覆层对α-MnO_(2)电化学性能的影响机制。结果表明,DCDA包覆层的物理限域作用提高了α-MnO_(2)的结构稳定性并抑制了放电时锰的溶解。更重要的是,DCDA中具有孤对电子的氮原子与阳离子的静电相互作用,放电时可抑制Mn^(2+)的溶解,充电时可促进Mn^(2+)沉积,从而有效地抑制了锰活性物质的流失。与未改性的α-MnO_(2)阴极相比,α-MnO_(2)@DCDA正极的循环稳定性显著提高,在3 A/g的大电流密度下,1500次循环后仍然具有102.6 mA·h/g的稳定容量,容量保持率超过60%。这项工作为实现MnO_(2)基锌离子电池的稳定循环提供了一条有效途径。

Er^(3+) ion concentration effect on transient and steady-state behavior in Er^(3+):YAG crystal

The effect of Er3＋ ion concentration on transient and steady-state behavior in 45-nm Er3＋ ：YAG crystal is investigated. It is shown that by changing the signal field, the coherent field and the concentration of Er3＋ ions in the crystal, the absorption, dispersion, and group index of the weak probe field can be adjusted. Also, it is found that the probe absorption occurs in the presence of population inversion and probe amplification is obtained in the absence of population inversion.

Chloride Ion Transmission Model under the Drying-wetting Cycles and Its Solution

The chloride ion transmission model considering diffusion and convection was established respectively for different zones in concrete by analyzing chloride ion transmission mechanism under the dryingwetting cycles. The finite difference method was adopted to solve the model. The equation of chloride ion transmission model in the convection and diffusion zone of concrete was discreted by the group explicit scheme with right single point （GER method） and the equation in diffusion zone was discreted by FTCS difference scheme. According to relative humidity characteristics in concrete under drying-wetting cycles, the seepage velocity equation was formulated based on Kelvin Equation and Darcy＇s Law. The time-variant equations of chloride ion concentration of concrete surface and the boundary surface of the convection and diffusion zone were established. Based on the software MATLAB the numerical calculation was carried out by using the model and basic material parameters from the experiments. The calculation of chloride ion concentration distribution in concrete is in good agreement with the drying-wetting cycles experiments. It can be shown that the chloride ion transmission model and the seepage velocity equation are reasonable and practical. Studies have shown that the chloride ion transmission in concrete considering convection and diffusion under the drying-wetting cycles is the better correlation with the actual situation than that only considering the diffusion.

GRAFT POLYMERIZATION OF ACRYLAMIDE ONTO HOMOPOLYMER OF 5-METHYL-5-HEXEN-2, 4-DIONE INITIATED BY CERIC ION

The homopolymerization of 5-methyl-5-hexen-2,4-dione (methacryloylacetone, MAA), a vinyl monomer having beta-diketone group, was carried out in the presence of benzophenone (BP)/N, N-dimenthyl-4-toluidine (DMT) system. Graft polymerization of acrylamide initiated by eerie ion onto the homopolymer film was investigated and the mechanism of the grafting reaction was proposed on the basis of ESR study. The grafted copolymer was characterized by means of grafting percentage, water absorption, XPS spectra and scanning electron photomicrographs.

Synthesis and Characterization of the Endohedral Plumbaspherene[Rh@Pb_(12)]^(3-)

The endohedral plumbaspherene cluster anion [Rh@Pbl2]3- was synthesized by the reaction of K4Pb9 with Rh（PPh3）3Cl in ethylenediamine （en） solution in the presence of 18-crown-6 （1,4,7,10,13,16-hexaoxacyclooctadecane）, and characterized by single-crystal X-ray diffraction and energy-dispersive X-ray （EDX） analysis. The novel zintl ion cluster [Rh@Pbl2]^- represents the first structurally characterized plumbaspherene Pb12 cluster with Ih point symmetry encapsulating a group 9 element in a spherical tetrel deltahedron. And the discovery of anion [Rh@Pb12]3- also provides direct proof for previous reports on the observation of [M@Pb12]x± （clusters in mass spectrometric experiments proved by quantum-chemical calculations）. DFT computations indicate that the icosahedral cluster anion [Rh@Pb12]3- is isostructural and isoelectronic with [Ir@Sn12]3-.

叔胺型响应表面活性剂的合成及性能研究

以油酸和N,N-二甲基-1,3-丙二胺为原料,氟化钠为催化剂,合成了一种具有CO_(2)响应性的长链叔胺(油酸酰胺丙基二甲基叔胺(DMOA)),测定了其通入CO_(2)和N2下的电导率,证实了合成的DMOA溶液具有CO_(2)响应性能。测定了在通入CO_(2)下DMOA与反离子复配的表面张力,发现将DMOA与二元反离子草酸钠复配能显著降低溶液的表面张力。研究了DMOA与草酸钠复配体系的黏度的CO_(2)响应性能,结果表明,复配体系能够显著提高体系的黏度,并具有CO_(2)响应性和循环可逆性。研究了复配体系的起泡性能和在石蜡膜上的接触角,发现在通入了CO_(2)条件下,复配体系能够降低起泡性能和与疏水表面的接触角。

功能化聚芳醚酮固载铜离子抑菌膜制备及表征

为了使微孔滤膜具有抑菌功能,以自制的侧链含苯并咪唑结构聚芳醚酮为膜材料,利用苯并咪唑基团与Cu^(2+)间的配位作用,通过非溶剂致相分离法(NIPS)和金属离子配位改性法制备抑菌型微孔滤膜。对固载Cu^(2+)前后的微滤膜的微观结构、抗污性能、抑菌性能、耐溶剂性能以及膜的Cu^(2+)固载量等进行测试与表征。结果表明,Cu^(2+)能够被固载至含有苯并咪唑结构的微孔滤膜上。所制备的Cu^(2+)螯合膜对大肠杆菌的抑制率可达63%,且随着开孔率的增加,膜的抑菌性能有所提升。其中,抑菌圈实验和Cu^(2+)流失速率测试实验进一步说明了Cu^(2+)与聚合物分子链上的苯并咪唑基团间的相互作用能够将Cu^(2+)约束在膜内,有效缓解金属离子流失现象。

两性纤维素基吸附剂的制备及其吸附性能研究

本研究以蔗渣制备的微晶纤维素为基体,以含氨基和羧基的两性小分子为功能试剂,以环氧氯丙烷为交联剂,采用交联法制备了一种具有高羧基含量(5.11 mmol/g)和氨基含量(7.43 mmol/g)的两性纤维素基吸附剂,并解析了重金属离子在其表面的竞争吸附行为和吸附动力学。结果表明,该吸附剂可在120 min内将1.0 mg/L的Cr(Ⅵ)、Pb(Ⅱ)、Cd(Ⅱ)和2.0 mg/L的Cu(Ⅱ)同步去除至0.0030 mg/L以下,使溶液中重金属离子残余浓度符合国家安全饮用水标准GB 5749—2022,实现了低浓度多种重金属离子的同步高效去除;吸附剂对重金属离子的吸附吻合Langmuir吸附等温线模型,以单层化学吸附为主,对Cr(Ⅵ)、Cu(Ⅱ)、Pb(Ⅱ)和Cd(Ⅱ)的理论最大吸附容量分别为373.1、128.4、134.4和113.3 mg/g。

优化炭表面氧官能团增强锌离子电容器的电容性能

锌离子电容器(ZICs)具有能量密度高、倍率性能好、循环寿命长、成本低等优点,近年来得到了广泛的研究。在碳基阴极表面引入氧官能团是提高水系ZICs电容性能的有效策略。然而,氧官能团的存在是否有利于提高乙醇(EtOH)基ZICs的电容性能,目前还没有被深入研究。本文采用硝酸氧化和进一步热处理的方法对阴极活性炭表面的氧官能团进行了优化。在ZnCl2/EtOH电解液中,优化后的样品在电流密度为1 A g^(−1)时比电容达到195 F g^(−1),比未改性的样品(125 F g^(−1))提高了56%。同时,ZICs也表现出良好的循环稳定性,在3 A g^(−1)下的稳定循环次数超过16000次,并且保持100%的库仑效率。这是因为氧官能团,特别是羧基和酯基(―COO)的存在,为Zn2+氧化还原反应提供了丰富的电化学活性位点。因此,本研究通过优化氧官能团增强了炭阴极的电容性能,并为EtOH基ZICs的商业应用提供了研究基础。

官能团调控对石墨烯正极电化学性能的影响

为了系统分析石墨烯正极材料中含氧官能团的量对材料电化学性能的影响,通过氧化石墨的低温膨胀法及后处理手段制备出3种不同官能团含量的石墨烯粉体材料,并进行了系统的理化表征和电化学性能表征。结果表明,当石墨烯材料用作锂离子电容器正极时,在其比表面积略微降低的前提下,若氧原子摩尔分数提高约14.5%,可逆比容量提升约13.4%;若氧原子摩尔分数降低约79%,可逆比容量降低约80.1%。说明含氧官能团的量是影响材料可逆比容量的关键因素。将此类石墨烯正极材料应用于软包型锂离子电容器器件中,器件表现出较好的电化学特性(在60 C充放电倍率下,器件容量保持率仍有47%)。