Hg-CEMS烟气预处理关键问题研究与进展

鉴于汞在化石燃料和矿物资源中的天然禀赋以及能源与资源利用过程中汞污染物的排放与监管,研发我国自主知识产权的汞连续在线监测系统(Hg-CEMS)成为汞排放浓度监测的国家重大需求。烟气预处理技术是Hg-CEMS系统中最关键的组成部分,也是限制我国Hg-CEMS技术发展与应用的核心技术。对Hg-CEMS烟气预处理技术中的4个关键模块——稀释采样模块、Hg0/Hg^(2+)分离模块、Hg^(2+)还原模块、Hg^(2+)标气发生模块的研究进展进行全面综述。首先,介绍稀释采样技术的原理与应用,阐述音速小孔和热稀释引射器的结构和设计要点,论述数值模拟与优化设计相结合的方法。其次,针对Hg0/Hg^(2+)分离技术,综述湿法吸收、物理吸附和化学吸附的研究新进展,讨论选择性吸附剂KCl和CaO的理论和实验研究结果。第3,针对Hg^(2+)还原技术,概述湿化学还原、低温还原和高温分解还原的技术,论证低温还原技术中固态还原剂的活性成分、反应温度以及烟气成分对氧化态汞还原的影响,探讨高温分解还原技术中填充材料、酸性气体组分以及除酸剂对Hg^(2+)还原和抑制Hg0再氧化的新研究进展。最后,针对Hg^(2+)标气发生技术面临的技术难点,提出固态标气发生新技术理念并指出其工业应用的可行性。结合当前Hg-CEMS技术的研究发展和应用现状,提出上述4个关键模块的研究思路、解决方案与应用前景。

COPD患者lncRNA MIR155HG表达与肺功能的相关性及其对AECODP的辅助诊断价值

目的 探讨慢性阻塞性肺疾病(COPD)患者长链非编码RNA(lnc RNA) MIR155HG与肺功能的相关性,及其对慢性阻塞性肺疾病急性加重(AECOPD)的辅助诊断价值。方法 选取2018年10月—2021年3月南阳市中心医院COPD患者117例,其中稳定期患者60例(稳定期组)、AECOPD患者57例(AECOPD组),以60名健康体检者作为正常对照组。收集所有研究对象一般资料,并检测肺功能[第1秒用力呼气容积(FEV1)、用力肺活量(FVC),计算FEV1/FVC%和外周血单个核细胞(PBMC)中lnc RNAMIR155HG的表达。采用Logistic回归分析评估AECOPD的危险因素。采用受试者工作特征(ROC)曲线评价各项指标诊断AECOPD的效能。结果 AECOPD组、稳定期组、正常对照组白细胞(WBC)计数、中性粒细胞百分比(NEUT%)、降钙素原(PCT)、C反应蛋白(CRP)、纤维蛋白原(Fib)、PBMC中lnc RNA MIR155HG相对表达量依次降低(P<0.05),FEV1和FEV1/FVC%依次升高(P<0.05)。稳定期组和AECOPD组PBMC中lnc RNA MIR155HG相对表达量与WBC计数、NEUT%、PCT、CRP和Fib水平均呈正相关(P<0.001),与FEV1和FEV1/FVC%均呈负相关(P<0.001)。Logistic回归分析结果显示,lnc RNAMIR155HG表达升高、FEV1降低是发生AECOPD的危险因素[比值比(OR)值分别为2.381、0.682,95%可信区间(CI)分别为1.526~3.715、0.531~0.876]。ROC曲线分析结果显示,FEV1、lnc RNA MIR155HG单项和联合检测诊断AECOPD的曲线下面积(AUC)分别为0.826、0.854、0.939。结论 COPD患者PBMC中lnc RNA MIR155HG水平升高,且与炎症指标和肺功能相关,或可作为AECOPD的早期诊断标志物。

基于HGS-IDWA算法的机器人路径规划研究

针对机器人路径规划问题,提出了融合饥饿游戏搜索(HGS)算法和改进动态窗口(IDWA)算法的优化思路。首先,利用HGS算法进行静态规划;其次,在动态规划阶段,针对传统DWA算法的路径选择不合理问题,引入新的目标函数以优化接近目标时的速度选择,在速度函数中加入障碍物数量以提升动态规划效率;最后,通过案例仿真与实地测试,分析机器人在规避动态障碍时获得的最佳路径。

一种具有识别Hg^(2+)和ClO^(-)荧光探针的设计和应用

设计合成了一种含双酯基的1,2,3-三氮唑化合物,与罗丹明B酰肼结合生成了具有“开-关”性质的荧光探针(简称L_(2)),应用光谱学表征了L_(2)的物理化学参数。L_(2)分别在DMF/Tris-HCl(1:1,v/v,pH=6.0,20μmol/L)和MeOH(20μmol/L)溶液中对Hg^(2+)和ClO^(-)显示出高选择性和灵敏性;利用荧光和紫外光谱分别测定了L_(2)对19种金属离子和14种阴离子的光学性能。实验表明,Hg^(2+)和ClO^(-)的存在使得L_(2)在585 nm和576 nm均有一个新的发射峰出现;同时伴随着荧光强度明显的增强,溶液体系发生了裸眼能识别的显色变化,表明Hg^(2+)可以将罗丹明分子的酰肼闭环结构转换为开环结构,并以1:2的比例方式生成了一种新配合物,这也被质谱、工作曲线、核磁滴定和TD-DFT计算的结果所证实;L_(2)对Hg^(2+)和ClO^(-)的检测限分别为7.45 nmol/L和0.67μmol/L。此外,生物活性测定显示L_(2)对HeLa细胞有非常低的毒性,并且可用于HeLa细胞中Hg^(2+)和ClO^(-)的细胞成像,表明L_(2)在体内可进行微测定Hg^(2+)和ClO^(-)的巨大潜力。

lncRNA-miR210HG在NSCLC患者癌组织中的表达及其临床意义

目的分析非小细胞肺癌(NSCLC)患者癌组织中长链非编码RNA(lncRNA)-miR210HG的表达及其临床意义。方法选取84例NSCLC患者,比较其癌组织及癌旁组织中lncRNA-miR210HG水平。按照lncRNA-miR210HG表达水平将患者分为高表达组和低表达组,比较两组临床病理参数和生存情况。多因素COX回归模型分析影响NSCLC患者预后的危险因素。结果NSCLC癌组织miR210和lncRNA-miR210HG表达水平均高于癌旁组织(P<0.05)。Ⅲ期、存在淋巴结转移的患者癌组织中lncRNA-miR210HG高表达者占比较高(P<0.05),高表达组总生存率和无进展生存率低于低表达组(P<0.05)。l ncRNA-miR210HG是影响NSCLC患者预后的独立危险因素(P<0.05)。结论NSCLC癌组织中lncRNA-miR210HG高表达与有无淋巴转移、临床分期有关,lncRNA-miR210HG是影响NSCLC患者预后的独立危险因素。

lncRNA-miR210HG、SH3BGRL3表达在非小细胞肺癌患者中的临床意义

目的分析长链非编码RNA(lncRNA)-miR210HG、SH3BGRL3表达在非小细胞肺癌(NSCLC)患者中的临床意义。方法选取76例NSCLC患者,比较癌组织和癌旁组织中lncRNA-miR210HG和SH3BGRL3 mRNA阳性表达率,并将患者分为阳性组和阴性组。比较lncRNA-miR210HG、SH3BGRL3阳性和阴性表达与临床病理特征的关系。比较各组生存情况。结果癌组织中lncRNA-miR210HG、SH3BGRL3表达水平高于癌旁组织(P<0.05)。lncRNA-miR210HG阳性表达者Ⅲ期占比、淋巴结转移占比高于阴性表达者;SH3BGRL3阳性表达者Ⅲ期占比、淋巴结转移占比、低中分化占比高于阴性表达者(P<0.05)。lncRNA-miR210HG、SH3BGRL3阳性组总生存率均低于阴性组(P<0.05)。结论lncRNA-miR210HG、SH3BGRL3在NSCLC癌组织中高表达,不同表达水平者TNM分期、淋巴结转移、分化程度不同。

基于涤棉混纺织物的荧光碳点对Cr(Ⅵ)和Hg(Ⅱ)的检测

该文以废弃涤棉混纺织物为碳源,分别在乙二醇和硫酸溶液中通过溶剂热法合成了两种荧光碳点,实现了对溶液中Cr(Ⅵ)和Hg(Ⅱ)的检测。通过透射电镜与红外光谱表征了碳点的形貌与组成,并基于紫外吸收光谱和荧光光谱分析了碳点的电子跃迁形式及发光类型。在乙二醇体系中制得的碳点(ETCCDs)能够选择性检测Cr(Ⅵ),检出限为0.093 mg/L,其检测机理为荧光内滤效应;硫酸体系中制备的碳点(WTCCDs)能够选择性检测Hg(Ⅱ),检出限为0.018µmol/L,检测机理为能量转移。对实际水样中的Cr(Ⅵ)和Hg(Ⅱ)进行检测,验证了上述两种碳点的实用性。基于涤棉混纺织物制备的荧光碳点不仅实现了对两种重金属离子的检测,同时也为废旧纺织物的再生利用提供了借鉴意义。

特大型替打环用钢HG80的连续冷却相变行为

通过Formastor-F II热膨胀相变仪对HG80钢在连续冷却过程中的热膨胀曲线进行测定,结合微观组织和维氏硬度绘制其连续冷却转变曲线(CCT曲线),分析不同冷却速度对其组织转变的影响。结果表明:在连续冷却过程中,HG80钢发生了奥氏体向铁素体、珠光体、贝氏体和马氏体的相变;当冷却速度小于0.1℃/s时,HG80钢的组织为铁素体和珠光体,此时显微硬度较低,为214 HV2;当冷却速度为0.3~0.5℃/s时,组织为铁素体、珠光体和贝氏体,显微硬度增加到240 HV2;当冷却速度升高到3℃/s时,组织为铁素体和贝氏体,显微硬度为299 HV2;当冷却速度为5~20℃/s时,组织为贝氏体和马氏体,显微硬度快速增加;当冷却速度大于20℃/s时,只发生马氏体转变,显微硬度达到最高,为571 HV2。

An Environment‑Tolerant Ion‑Conducting Double‑Network Composite Hydrogel for High‑Performance Flexible Electronic Devices

High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic devices.However,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use in soft electronics.To resolve these issues,a method involving freeze–thawing and ionizing radiation technology is reported herein for synthesizing a novel double-network(DN)ICH based on a poly(ionic liquid)/MXene/poly(vinyl alcohol)(PMP DN ICH)system.The well-designed ICH exhibits outstanding ionic conductivity(63.89 mS cm^(-1) at 25℃),excellent temperature resistance(-60–80℃),prolonged stability(30 d at ambient temperature),high oxidation resist-ance,remarkable antibacterial activity,decent mechanical performance,and adhesion.Additionally,the ICH performs effectively in a flexible wireless strain sensor,thermal sensor,all-solid-state supercapacitor,and single-electrode triboelectric nanogenerator,thereby highlighting its viability in constructing soft electronic devices.The highly integrated gel structure endows these flexible electronic devices with stable,reliable signal output performance.In particular,the all-solid-state supercapacitor containing the PMP DN ICH electrolyte exhibits a high areal specific capacitance of 253.38 mF cm^(-2)(current density,1 mA cm^(-2))and excellent environmental adaptability.This study paves the way for the design and fabrication of high-performance mul-tifunctional/flexible ICHs for wearable sensing,energy-storage,and energy-harvesting applications.

Ionization Engineering of Hydrogels Enables Highly Efficient Salt‑Impeded Solar Evaporation and Night‑Time Electricity Harvesting

Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy utilization.Hydrogels,as a tunable material platform from the molecular level to the macroscopic scale,have been considered the most promising candidate for solar evaporation.However,the simultaneous achievement of high evaporation efficiency and satisfactory tolerance to salt ions in brine remains a challenging scientific bottleneck,restricting the widespread application.Herein,we report ionization engineering,which endows polymer chains of hydrogels with electronegativity for impeding salt ions and activating water molecules,fundamentally overcoming the hydrogel salt-impeded challenge and dramatically expediting water evaporating in brine.The sodium dodecyl benzene sulfonate-modified carbon black is chosen as the solar absorbers.The hydrogel reaches a ground-breaking evaporation rate of 2.9 kg m−2 h−1 in 20 wt%brine with 95.6%efficiency under one sun irradiation,surpassing most of the reported literature.More notably,such a hydrogel-based evaporator enables extracting clean water from oversaturated salt solutions and maintains durability under different high-strength deformation or a 15-day continuous operation.Meantime,on the basis of the cation selectivity induced by the electronegativity,we first propose an all-day system that evaporates during the day and generates salinity-gradient electricity using waste-evaporated brine at night,anticipating pioneer a new opportunity for all-day resource-generating systems in fields of freshwater and electricity.

In Situ Deposition of Drug and Gene Nanoparticles on a Patterned Supramolecular Hydrogel to Construct a Directionally Osteochondral Plug

The integrated repair of bone and cartilage boasts advantages for osteochondral restoration such as a long-term repair effect and less deterioration compared to repairing cartilage alone.Constructing multifactorial,spatially oriented scaffolds to stimulate osteochondral regeneration,has immense significance.Herein,targeted drugs,namely kartogenin@polydopamine(KGN@PDA)nanoparticles for cartilage repair and miRNA@calcium phosphate(miRNA@CaP)NPs for bone regeneration,were in situ deposited on a patterned supramolecular-assembled 2-ureido-4[lH]-pyrimidinone(UPy)modified gelation hydrogel film,facilitated by the dynamic and responsive coordination and complexation of metal ions and their ligands.This hydrogel film can be rolled into a cylindrical plug,mimicking the Haversian canal structure of natural bone.The resultant hydrogel demonstrates stable mechanical properties,a self-healing ability,a high capability for reactive oxygen species capture,and controlled release of KGN and miR-26a.In vitro,KGN@PDA and miRNA@CaP promote chondrogenic and osteogenic differentiation of mesenchymal stem cells via the JNK/RUNX1 and GSK-3β/β-catenin pathways,respectively.In vivo,the osteochondral plug exhibits optimal subchondral bone and cartilage regeneration,evidenced by a significant increase in glycosaminoglycan and collagen accumulation in specific zones,along with the successful integration of neocartilage with subchondral bone.This biomaterial delivery approach represents a significant toward improved osteochondral repair.

A Generic Strategy to Create Mechanically Interlocked Nanocomposite/Hydrogel Hybrid Electrodes for Epidermal Electronics

Stretchable electronics are crucial enablers for next-generation wearables intimately integrated into the human body.As the primary compliant conductors used in these devices,metallic nanostructure/elastomer composites often struggle to form conformal contact with the textured skin.Hybrid electrodes have been consequently developed based on conductive nanocomposite and soft hydrogels to establish seamless skin-device interfaces.However,chemical modifications are typically needed for reliable bonding,which can alter their original properties.To overcome this limitation,this study presents a facile fabrication approach for mechanically interlocked nanocomposite/hydrogel hybrid electrodes.In this physical process,soft microfoams are thermally laminated on silver nanowire nanocomposites as a porous interface,which forms an interpenetrating network with the hydrogel.The microfoam-enabled bonding strategy is generally compatible with various polymers.The resulting interlocked hybrids have a 28-fold improved interfacial toughness compared to directly stacked hybrids.These electrodes achieve firm attachment to the skin and low contact impedance using tissue-adhesive hydrogels.They have been successfully integrated into an epidermal sleeve to distinguish hand gestures by sensing mus-cle contractions.Interlocked nanocomposite/hydrogel hybrids reported here offer a promising platform to combine the benefits of both materials for epidermal devices and systems.

Mechanical reliable,NIR light-induced rapid self-healing hydrogel electrolyte towards flexible zinc-ion hybrid supercapacitors with low-temperature adaptability and long service life

Hydrogel electrolytes hold great potential in flexible zinc ion supercapacitors(ZICs)due to their high conductivity,good safety,and flexibility.However,freezing of electrolytes at low temperature(subzero)leads to drastic reduction in ionic conductivity and mechanical properties that deteriorates the performance of flexible ZICs.Besides,the mechanical fracture during arbitrary deformations significantly prunes out the lifespan of the flexible device.Herein,a Zn^(2+)and Li^(+)co-doped,polypyrrole-dopamine decorated Sb_(2)S_(3)incorporated,and polyvinyl alcohol/poly(N-(2-hydroxyethyl)acrylamide)double-network hydrogel electrolyte is constructed with favorable mechanical reliability,anti-freezing,and self-healing ability.In addition,it delivers ultra-high ionic conductivity of 8.6 and 3.7 S m^(-1)at 20 and−30°C,respectively,and displays excellent mechanical properties to withstand tensile stress of 1.85 MPa with tensile elongation of 760%,together with fracture energy of 5.14 MJ m^(-3).Notably,the fractured hydrogel electrolyte can recover itself after only 90 s of infrared illumination,while regaining 83%of its tensile strain and almost 100%of its ionic conductivity during−30–60°C.Moreover,ZICs coupled with this hydrogel electrolyte not only show a wide voltage window(up to 2 V),but also provide high energy density of 230 Wh kg^(-1)at power density of 500 W kg^(-1)with a capacity retention of 86.7%after 20,000 cycles under 20°C.Furthermore,the ZICs are able to retain excellent capacity even under various mechanical deformation at−30°C.This contribution will open up new insights into design of advanced wearable flexible electronics with environmental adaptability and long-life span.

1,3-氧硫戊环为受体的Hg^(2+)荧光探针的设计、合成及性能

Hg^(2+)是毒性最强的重金属离子之一,会造成空气、土壤和水的污染,严重损害人体健康,开发有效的分析方法检测环境体系中的Hg^(2+)尤为重要。荧光探针因其灵敏度高、选择性好、响应速度快、可实时在线检测等优点,已广泛应用于Hg^(2+)检测。以Hg^(2+)促进硫代缩醛的去保护反应设计合成了一种全新的以1,3-氧硫戊环为受体的开启型Hg^(2+)荧光探针[2-(pyren-1-yl)-1,3-oxathiolane,POX],通过^(1)H NMR、^(13)C NMR和HRMS对POX结构进行表征,考察了POX在CH_(3)CH_(2)OH/H_(2)O中对Hg^(2+)的选择性、竞争性、浓度滴定、pH滴定、时间依赖性、检出限和识别机理等。研究结果表明,POX可在较宽的pH范围内对Hg^(2+)快速识别,并表现出高度的选择性和灵敏度;向POX中加入Hg^(2+)后,在386 nm处出现明显的荧光发射峰,表明POX对Hg^(2+)呈现出显著的荧光“开启”效应,其识别过程几乎不受其他金属离子干扰;荧光滴定实验表明POX在Hg^(2+)浓度为0~6.5μmol·L^(-1)范围内具有良好的线性响应(R^(2)=0.9994),检出限为0.168μmol·L^(-1),在实际水样中检测Hg^(2+)的RSD小于2.92%。由于POX合成简单、原料易得且pH适用范围较广,可作为定性和定量检测环境中Hg^(2+)的潜在工具。

Reconstruction of Postinfarcted Cardiac Functions Through Injection of Tanshinone ⅡA@Reactive Oxygen Species-Sensitive Microspheres Encapsulated in a Thermoreversible Hydrogel

Myocardial damage resulting from acute myocardial infarction often leads to progressive heart failure and sudden death,highlighting the urgent clinical need for effective therapies.Recently,tanshinoneⅡA has been identified as a promising therapeutic agent for myocardial infarction.However,efficient delivery remains a major issue that limits clinical translation.To address this problem,an injectable thermosensitive poly(lactic acid-co-glycolic acid)-block-poly(ethylene glycol)-block-poly(lactic acid-co-glycolic acid)gel(PLGA-PEG-PLGA)system encapsulating tanshinoneⅡA-loaded reactive oxygen species-sensitive microspheres(Gel-MS/tanshinoneⅡA)has been designed and synthesized in this study.The thermosensitive hydrogel exhibits good mechanical properties after reaching body temperature.Microspheres initially immobilized by the gel exhibit excellent reactive oxygen species-triggered release properties in a high-reactive oxygen species environment after myocardial infarction onset.As a result,encapsulated tanshinoneⅡA is effectively released into the infarcted myocardium,where it exerts local anti-pyroptotic and anti-inflammatory effects.Importantly,the combined advantages of this technique contribute to the mitigation of left ventricular remodeling and the restoration of cardiac function following tanshinoneⅡA.Therefore,this novel,precision-guided intra-tissue therapeutic system allows for customized local release of tanshinoneⅡA,presenting a promising alternative treatment strategy aimed at inducing beneficial ventricular remodeling in the post-infarct heart.

A Polyvinyl Alcohol/Acrylamide Hydrogel with Enhanced Mechanical Properties Promotes Full-Thickness Skin Defect Healing by Regulating Immunomodulation and Angiogenesis Through Paracrine Secretion

Hydrogel-based tissue-engineered skin has attracted increased attention due to its potential to restore the structural integrity and functionality of skin.However,the mechanical properties of hydrogel scaffolds and natural skin are substantially different.Here,we developed a polyvinyl alcohol(PVA)/acrylamide based interpenetrating network(IPN)hydrogel that was surface modified with polydopamine(PDA)and termed Dopa-gel.The Dopa-gel exhibited mechanical properties similar to native skin tissue and a superior ability to modulate paracrine functions.Furthermore,a tough scaffold with tensile resistance was fabricated using this hydrogel by three-dimensional printing.The results showed that the interpenetration of PVA,alginate,and polyacrylamide networks notably enhanced the mechanical properties of the hydrogel.Surface modification with PDA endowed the hydrogels with increased secretion of immunomodulatory and proangiogenic factors.In an in vivo model,Dopa-gel treatment accelerated wound closure,increased vascularization,and promoted a shift in macrophages from a proinflammatory M1 phenotype to a prohealing and anti-inflammatory M2 phenotype within the wound area.Mechanistically,the focal adhesion kinase(FAK)/extracellular signal-related kinase(ERK)signaling pathway may mediate the promotion of skin defect healing by increasing paracrine secretion via the Dopa-gel.Additionally,proangiogenic factors can be induced through Rho-associated kinase-2(ROCK-2)/vascular endothelial growth factor(VEGF)-mediated paracrine secretion under tensile stress conditions.Taken together,these findings suggest that the multifunctional Dopa-gel,which has good mechanical properties similar to those of native skin tissue and enhanced immunomodulatory and angiogenic properties,is a promising scaffold for skin tissue regeneration.

Hydrogel loaded with bone marrow stromal cell-derived exosomes promotes bone regeneration by inhibiting inflammatory responses and angiogenesis

BACKGROUND Bone healing is a complex process involving early inflammatory immune regu-lation,angiogenesis,osteogenic differentiation,and biomineralization.Fracture repair poses challenges for orthopedic surgeons,necessitating the search for efficient healing methods.AIM To investigate the underlying mechanism by which hydrogel-loaded exosomes derived from bone marrow mesenchymal stem cells(BMSCs)facilitate the process of fracture healing.METHODS Hydrogels and loaded BMSC-derived exosome(BMSC-exo)gels were charac-terized to validate their properties.In vitro evaluations were conducted to assess the impact of hydrogels on various stages of the healing process.Hydrogels could recruit macrophages and inhibit inflammatory responses,enhance of human umbilical vein endothelial cell angiogenesis,and promote the osteogenic differen-tiation of primary cranial osteoblasts.Furthermore,the effect of hydrogel on fracture healing was confirmed using a mouse fracture model.RESULTS The hydrogel effectively attenuated the inflammatory response during the initial repair stage and subsequently facilitated vascular migration,promoted the formation of large vessels,and enabled functional vascularization during bone repair.These effects were further validated in fracture models.CONCLUSION We successfully fabricated a hydrogel loaded with BMSC-exo that modulates macrophage polarization and angiogenesis to influence bone regeneration.

基于点击-去点击化学反应的Hg^(2+)荧光探针检测体系构建

基于杂化罗丹明与巯基化合物之间的点击化学反应及巯基化合物与金属汞离子的配位反应导致的去点击化学反应机理,构建香豆素杂化罗丹明探针-1,3,5-苯三硫酚-Hg^(2+)的三元荧光检测体系。在该体系中,探针能够与1,3,5-苯三硫酚中的巯基基团发生加成反应,破坏探针的共轭结构,从而导致探针的红色荧光猝灭。加入Hg^(2+)后,Hg^(2+)与1,3,5-苯三硫酚通过配位作用结合,使其从探针结构上离去,探针的共轭结构及红色荧光恢复。体系的荧光强度与Hg^(2+)在5×10^(-9)~1×10^(-8)、1×10^(-8)~1.1×10^(-7)mol/L浓度范围内呈良好的线性关系,检测限为2×10^(-9)mol/L,等倍量的常见重金属离子对Hg^(2+)的特异性识别无干扰。应用于实际饮用水样品中Hg^(2+)含量检测,回收率可达到86.7%~110.2%。

基于N掺杂Ti_(3)C_(2)MXene量子点的荧光探针用于Hg2+和S2-的传感检测

基于N掺杂Ti_(3)C_(2) MXene量子点(N-Ti_(3)C_(2) MQDs)荧光探针和配位相互作用,构建了一种检测Hg^(2+)和S^(2-)的“开-关-开”型荧光传感新方法.研究发现,制备的N-Ti_(3)C_(2) MQDs发射蓝色荧光(λem=440 nm),荧光量子产率为15.7%.Hg^(2+)与N-Ti_(3)C_(2) MQDs表面的—NH2,—COOH,—OH等官能团产生选择性配位作用,导致N-Ti_(3)C_(2) MQDs体系荧光猝灭.当加入S^(2-)后,由于S^(2-)与Hg^(2+)之间强的结合力,形成HgS沉淀,从而使N-Ti_(3)C_(2) MQDs体系荧光恢复.基于该原理,构建了一种“开-关-开”型荧光传感方法,实现了对Hg^(2+)和S^(2-)的定量检测.N-Ti_(3)C_(2) MQDs探针的荧光强度与Hg^(2+)浓度在0.02~200μmol/L范围内呈良好线性关系,检出限为10 nmol/L(S/N=3);与S^(2-)浓度在0.07~150μmol/L范围内呈良好线性关系,检出限为30 nmol/L(S/N=3).该方法具有成本低、操作简单、灵敏度高和选择性好等特点,并可用于水样中Hg^(2+)和S^(2-)的检测.

氨基酸基氮掺杂荧光碳点的制备及饮料中Hg^(2+)的检测

汞离子是一种高毒性的重金属污染物,人体摄入后会带来健康危害,因此控制食品中的汞离子含量非常重要。以柠檬酸为碳源,不同的氨基酸为氮源掺杂,采用一步水热法制备高性能荧光的碳点(CDs),探究不同氨基酸基氮掺杂对碳点荧光量子产率(QY)的影响,以及这些氨基酸基氮掺杂碳点对汞离子的响应。结果显示,不同氨基酸的碳链长度和官能团对CDs的QY有一定的影响。Hg^(2+)能高效猝灭以甘氨酸(Gly)为氮源掺杂的Gly-CDs的荧光,Gly-CDs具有良好的荧光稳定性,在优化的试验条件下,用于Hg^(2+)检测的线性范围为0.00~7.00μmol/L和8.00~60.00μmol/L,检出限为0.20μmol/L。据此构建的荧光探针用于检测实际饮料样品中的Hg^(2+),回收率在90.08%~107.90%。该方法简便、快速、灵敏、适用于饮料中Hg^(2+)的测定。