文章建立了自动电位滴定法测定有机肥料中有机质的方法。确定了滴定的加液步长为0.05 mL,等当点识别标准为100 mV,在此条件下可获得圆滑的滴定曲线和准确的滴定结果。进行不同含量的有机肥标准样品的精密度及准确度考察,结果显示,相对...文章建立了自动电位滴定法测定有机肥料中有机质的方法。确定了滴定的加液步长为0.05 mL,等当点识别标准为100 mV,在此条件下可获得圆滑的滴定曲线和准确的滴定结果。进行不同含量的有机肥标准样品的精密度及准确度考察,结果显示,相对标准偏差在0.46%~0.81%之间,相对误差在−1.29%~3.3%之间,且测定结果均在标准值的不确定度范围之内。通过与经典滴定法的比对试验并对试验结果进行t检验及F检验,各试验组的t值均小于t (0.05, 2n-2)值,F值小于对应的临界值,即方法之间的准确度及精密度不存在显著性差异。建立的方法具有操作简便、准确可靠、重复性好、效率高等优点,适用于有机肥料中有机质含量的测定。A method for determining organic matter in organic fertilizers using automatic potentiometric titration has been established. The addition step size for titration has been determined to be 0.05 mL, and the identification standard for equivalent points is 100 mV. Under these conditions, a smooth titration curve and accurate titration results can be obtained. The precision and accuracy of organic fertilizer standard samples with different contents were investigated, and the results showed that the relative standard deviation was from 0.46% to 0.81%, and the relative error was from 0.3% to 3.3%. The measurement results were all within the uncertainty range of the standard values. Through the t-tests and F-tests, it was found that the t-values of each experimental group were less than the t (0.05, 2n-2) value, and the F-values were also less than the corresponding critical values, indicating that there was no significant difference in accuracy and precision between the methods. The method has the advantages of simple operation, accuracy and reliability, good repeatability, and high efficiency, and is suitable for the determination of organic matter content in organic fertilizers.展开更多
医用导管作为现代医疗中不可或缺的重要设备,广泛应用于药物输送、体液引流和病症诊疗等领域。其性能的优劣直接影响诊疗效果和患者的生命安全,而导管的材料和表面涂层的选择,则在改善其生物相容性、耐久性及抗菌性能方面起着至关重要...医用导管作为现代医疗中不可或缺的重要设备,广泛应用于药物输送、体液引流和病症诊疗等领域。其性能的优劣直接影响诊疗效果和患者的生命安全,而导管的材料和表面涂层的选择,则在改善其生物相容性、耐久性及抗菌性能方面起着至关重要的作用。文章系统性地综述了当前医用导管表面改性技术的研究进展,包括水凝胶涂层、润滑液体注入多孔表面、静电纺丝、沉积法以及等离子体处理法等。这些技术通过优化涂层的材料成分和微观结构,不仅显著提升了导管的抗菌性能、抗血栓能力和机械强度,还赋予其药物缓释、智能响应等多样化功能,为复杂医疗环境中的导管应用提供了重要解决方案。展望未来,生物可降解材料、纳米技术的引入以及材料科学与生物医学等多学科的深度融合,将为医用导管涂层的创新设计与临床转化提供强大动力,进一步推动其在精准医疗领域的广泛应用。Medical catheters, as indispensable devices in modern healthcare, are widely used in drug delivery, fluid drainage, and disease diagnosis and treatment. Their performance directly influences therapeutic outcomes and patient safety. The selection of catheter materials and surface coatings plays a critical role in improving biocompatibility, durability, and antibacterial properties. This paper systematically reviews the current advancements in medical catheter surface modification technologies, including hydrogel coatings, lubricated liquid-infused porous surfaces, electrospinning, deposition methods, and plasma treatment. These technologies optimize the material composition and microstructure of coatings, significantly enhancing the antibacterial properties, thrombus resistance, and mechanical strength of catheters. Furthermore, they endow catheters with diverse functionalities, such as drug release and intelligent responsiveness, providing crucial solutions for catheter applications in complex medical environments. Looking to the future, the incorporation of biodegradable materials, nanotechnology, and the deep integration of materials science and biomedicine will drive innovative designs and clinical translation of catheter coatings, further advancing their applications in the field of precision medicine.展开更多
硅基锂离子电池负极材料由于能量密度高、工作电压适中而受到全世界的关注,但硅基材料存在体积膨胀和动力学较差等缺陷,该问题严重限制了硅基负极材料的大规模应用。文章提出了一种将纳米尺寸的介孔Si颗粒封装在碳中的设计策略,该Si@C...硅基锂离子电池负极材料由于能量密度高、工作电压适中而受到全世界的关注,但硅基材料存在体积膨胀和动力学较差等缺陷,该问题严重限制了硅基负极材料的大规模应用。文章提出了一种将纳米尺寸的介孔Si颗粒封装在碳中的设计策略,该Si@C纳米复合材料的尺寸约为200 nm左右。将Si@C以不同比例(20 wt%、30 wt%、40 wt%)和石墨混合、球磨合成,从而最终制备得到硅–石墨锂离子电池负极材料,通过包覆的碳层和复合的石墨层提高LIBs的能量密度和高稳定性。在本工作的研究中我们发现Si@C/G (20 wt%)纳米复合材料在100次循环中表现出600 mAh∙g−1的高比容量,在0.5 A∙g−1的电流密度下实现了750次的稳定循环,展现了优秀的循环稳定性,平均充电/放电容量为360 mAh∙g−1。此外,在不同电流密度下测试了Si@C/G (20 wt%)复合电极,并在1 A∙g−1下显示出262 mAhg−1的相对较高的可逆容量。与其他两种复合材料相比,Si@C/G (20 wt%)表现出高容量和稳定性。Si@C/G (20 wt%)获得的电化学性能证明了低含量合成纳米硅与石墨的高兼容性。此外,碳涂层防止了充电/放电过程中Si的体积膨胀。这个想法可以应用于设计高能量密度LIB负极材料。Silicon-based anodes for lithium-ion batteries (LIBs) are attractive due to their high energy density, but challenges such as significant volume expansion and poor kinetics have limited their practical application. This work introduces a Si@C nanocomposite, where nano-sized mesoporous silicon particles are encapsulated in carbon, with particle sizes around 200nm. The Si@C was blended with graphite at ratios of 20 wt%, 30 wt%, and 40 wt%, then ball-milled to form composite anode materials. The Si@C/G (20 wt%) composite demonstrated superior electrochemical performance, maintaining a high specific capacity of 600 mAh∙g⁻¹ over 100 cycles and stable cycling up to 750 times at 0.5 A∙g⁻¹, with an average charge/discharge capacity of 360 mAh∙g⁻¹. At higher current densities, it showed good reversible capacity retention, reaching 262 mAh∙g⁻¹ at 1 A∙g⁻¹. The carbon coating effectively mitigated silicon’s volumetric changes during cycling, enhancing stability. This study highlights the effectiveness of integrating low-content nano-silicon with graphite for achieving high-performance LIB anodes, showcasing the potential of Si@C/G (20 wt%) composites for next-generation battery technology. Moreover, the carbon coating prevented the volume expansion of Si during the charge/discharge process. This concept can be applied in designing high-energy-density LIB anode materials.展开更多
目的:测定不同产地黑种草子挥发油中百里醌的含量。方法:将5种不同产地的黑种草子用两种不同化学提取方法提取挥发油,建立定量核磁共振波谱法测定挥发油中的百里醌。使用500 MHZ Bruker Avance III (TMS, δ = 0 ppm)核磁共振谱仪,以氖...目的:测定不同产地黑种草子挥发油中百里醌的含量。方法:将5种不同产地的黑种草子用两种不同化学提取方法提取挥发油,建立定量核磁共振波谱法测定挥发油中的百里醌。使用500 MHZ Bruker Avance III (TMS, δ = 0 ppm)核磁共振谱仪,以氖代氯仿为溶剂,在测定温度25℃、延迟时间2 s和扫描次数64的条件下扫描,通过化学移位及峰面积归一化法测定各黑种草子挥发油中百里醌相对百分比含量。结果:以化学位移在δ = 6.5 ppm与δ = 6.6 ppm处的百里醌的氢质子峰作为定量峰,其峰面积比与其质量比的线性回归方程为Y = 0.493x − 0.0005,相关系数为0.999。5种不同产地黑种草子挥发油中百里醌在方法1中测得USA1 (0.065%)、USA2 (0.093%)、USA3 (0.043%)、Tibe (0.043%)、Guangxi (0.062%)。在方法2中测得USA1 (0.263%)、USA2 (0.153%)、USA3 (0.037%)、Tibet (0.200%)、Guangxi (0.224%)。结论:分析结果表明,因产地及提取方法差异,黑种草子挥发油中百里醌含量测定是有差异的。文章通过测定不同产地黑种草子挥发油中的百里醌含量,为进一步研究开发黑种草子的药用价值奠定基础。Objective: To determine the content of quinone in volatile oil from black seed (Nigella) of different habitats. Methods: The essential oils were extracted from the seeds of black grass from five different habitats by two different chemical extraction methods, and the thymoquinone in the essential oils was determined by quantitative nuclear magnetic resonance spectroscopy. A 500 MHz Bruker Avance III (TMS, δ = 0 ppm) nuclear magnetic resonance spectrometer was used, with deuterochloroform as the solvent, at a measurement temperature of 25˚C, a delay time of 2 seconds, and 64 scans, to determine the relative percentage content of thymoquinone in the volatile oils of black grass seeds by chemical shift and peak area normalization. Results: Using the hydrogen proton peak of thymoquinone with a chemical shift at δ = 6.5 ppm and δ = 6.6 ppm as the quantitative peak, the peak area ratio of thymoquinone and its mass ratio were linear regression equation Y = 0.493x − 0.0005, the correlation coefficient was 0.999, and thymoquinone in volatile oils of black grass from five different habitats was determined as USA1 (0.065%), USA2 (0.093%), USA3 (0.043%), Tibet (0.043%), Guangxi (0.062%) in method 1. In method 2, USA1 (0.263%), USA2 (0.153%), USA3 (0.037%), Tibet (0.200%), and Guangxi (0.224%) were measured. Conclusion: The results showed that there were differences in the determination of thymoquinone content in the essential oil of Herba Nigella due to the differences in origin and extraction methods. In this paper, the content of thymoquinone in the essential oil of black seed grass from different habitats was determined to lay a foundation for further research and development of the medicinal value of black seed grass.展开更多
焦化废水具有高浓度、成分复杂、生物毒性高等特点,采用常规处理方式处理焦化废水具有很大的挑战性。与传统生物法、电化学相比,生物电化学系统(Bioelectrochemical System, BES)不仅具有同时去除焦化废水中碳质和氮质污染物的能力,而...焦化废水具有高浓度、成分复杂、生物毒性高等特点,采用常规处理方式处理焦化废水具有很大的挑战性。与传统生物法、电化学相比,生物电化学系统(Bioelectrochemical System, BES)不仅具有同时去除焦化废水中碳质和氮质污染物的能力,而且可以通过电强化微生物的协同作用,节省整个处理过程的能量消耗。但是,鲜有综述对生物电化学系统在处理焦化废水中的研究进行系统总结。因此,文章在回顾BES原理、类型、电极材料的基础上,总结了BES在焦化废水处理中的研究进展,并分析了其在去除有机污染物、氨氮等污染物方面的强化效果。通过这些系统的回顾,本综述不仅阐述了电强化微生物促进焦化废水中污染物的作用机理,提出了未来关于BES的研究方向,还展望了BES用于焦化废水处理的前景和挑战,从而促进了BES在焦化废水处理中的实际应用。Coking wastewater is characterized by high concentrations, complex composition, and high biological toxicity, making its treatment challenging using conventional methods. Compared to traditional biological and electrochemical processes, the Bioelectrochemical System (BES) not only have the capability to simultaneously remove carbon and nitrogen pollutants from coking wastewater but also enhance microbial activity through electrical stimulation, thereby reducing energy consumption in the treatment process. However, there is a lack of systematic reviews summarizing the research on BES in coking wastewater treatment. This paper reviews the principles, types, and electrode materials of BES, summarizes the research progress of BES in coking wastewater treatment, and analyzes its enhanced effects in removing organic pollutants and ammonia nitrogen. Through this systematic review, the mechanisms by which electrostimulation promotes pollutant removal in coking wastewater are elucidated, future research directions for BES are proposed, and the prospects and challenges of using BES for coking wastewater treatment are discussed, thereby facilitating the practical application of BES in this field.展开更多
柱芳烃是一类具有独特对称性和柱状空腔结构的新型人工合成大环分子,可通过简单的化学方法对其端基进行功能化修饰,目前已发展成为一类重要的大环基元分子用于构筑各种刺激响应的功能超分子组装材料。光是一种清洁、非侵入性和时空可控...柱芳烃是一类具有独特对称性和柱状空腔结构的新型人工合成大环分子,可通过简单的化学方法对其端基进行功能化修饰,目前已发展成为一类重要的大环基元分子用于构筑各种刺激响应的功能超分子组装材料。光是一种清洁、非侵入性和时空可控的外部刺激,具有光刺激响应特性的主–客体作用超分子体系受到广泛关注。文章总结了近年来在基于柱芳烃的光响应主–客体超分子组装体系和功能材料方面的重要研究进展,系统阐述了目前报道的光响应柱芳烃主–客体超分子组装体系的主要构筑策略和代表性应用。Pillar[n]arenes are a class of artificial synthetic macrocyclic molecules featuring unique symmetrical and pillar-shaped cavity structures, as well as facile functionalization by chemically modifying their end groups. These features have conferred pillar[n]arenes to be of fundamental importance as macrocyclic building blocks for the construction of copious stimuli-responsive functional supramolecular assembly systems and materials. Light represents a clean and noninvasive external stimulus with unique spatiotemporal controllability, which has attracted considerable attention to the development of photoresponsive host-vip supramolecular systems. This review mainly summarizes the recent progress on photoresponsive pillar[n]arene-based host-vip supramolecular assembly systems and functional materials, with systematical elaboration and perspectives on their construction strategies and applications of currently reported photoresponsive pillar[n]arene-based host-vip supramolecular assembly systems and materials.展开更多
共价有机骨架(COFs)是一类由共价键周期性连接的有机组分组成的晶态多孔有机聚合物。COFs材料通常因其本身所具有的大Π电子共轭体系表现出许多突出的特性,如高比表面积和孔隙率、高化学稳定性和热稳定性,对合成单体的不同选择使其结构...共价有机骨架(COFs)是一类由共价键周期性连接的有机组分组成的晶态多孔有机聚合物。COFs材料通常因其本身所具有的大Π电子共轭体系表现出许多突出的特性,如高比表面积和孔隙率、高化学稳定性和热稳定性,对合成单体的不同选择使其结构易调控。这些特殊的优势使COFs材料在光催化方面表现出卓越的性能。此外,通过离子掺杂可以显著提高COFs材料作为光催化剂的活性。文章综述了离子型COF基材料在光催化体系中的最新研究进展。首先,对离子型COFs (iCOFs)的制备方法进行了分析和比较。此外,还介绍了离子型COFs基材料光催化反应的基本原理以及光催化领域的最新研究进展。Covalent Organic Frameworks (COFs) are crystalline porous organic polymer composed of organic components periodically linked by covalent bonds. COF materials usually exhibit many outstanding properties due to their large Π electron-conjugated system, such as high specific surface area and porosity, high chemical stability, and thermal stability, and the different selections of synthetic monomers make their structures easy to regulate. These special advantages make COFs materials show remarkable performance in photocatalysis. In addition, the activity of COFs as photocatalysts can be significantly improved by ion doping. The recent progress of research on ionic COF-based materials in photocatalytic systems is reviewed in this paper. Firstly, the preparation methods of ionic COFs (iCOFs) were analyzed and compared. In addition, the basic principle of photocatalytic reaction of ionic COFs-based materials and the latest research progress in the field of photocatalysis are also reviewed.展开更多
近年来,水资源短缺问题越来越严重,基于吸附的大气水收集被认为是一种有效应对水资源短缺的新兴技术。共价有机框架结构(COFs)是一类新型的多孔结晶聚合物,由于其独特的结构特性使其能在气体存储与分离、催化、光电材料、及大气水收集...近年来,水资源短缺问题越来越严重,基于吸附的大气水收集被认为是一种有效应对水资源短缺的新兴技术。共价有机框架结构(COFs)是一类新型的多孔结晶聚合物,由于其独特的结构特性使其能在气体存储与分离、催化、光电材料、及大气水收集等领域展现出广阔的应用前景。文章综述了COFs在大气水收集中的应用研究,简单介绍了大气水收集技术及在基于吸附的大气水收集(Sorption-Based Atmospheric Water Harvesting, SAWH)领域应用的COFs。In recent years, water scarcity has become an increasingly pressing issue. One effective approach to addressing the imminent water shortage crisis is sorption-based atmospheric water harvesting (SAWH). Covalent organic frameworks (COFs) are a type of porous crystalline material. Due to its unique structural characteristics, it can show broad application prospects in the fields of gas storage and separation, catalysis, optoelectronic materials, and atmospheric water harvesting. Then, we summarize recent advances in using COF-based sorbents for atmospheric water harvesting and briefly introduce the technology of atmospheric water collection and the application of COFs in the field of sorption-based atmospheric water harvesting (SAWH).展开更多
水系锌离子电池(AZIBs)作为未来大规模电化学储能解决方案的候选者,已经获得了广泛的关注。它的吸引力在于它的成本效益、低排放、内在安全性和较高的能量密度。因此,高性能水系锌离子电池的设计和改进得到了广泛的研究。在这篇综述中,...水系锌离子电池(AZIBs)作为未来大规模电化学储能解决方案的候选者,已经获得了广泛的关注。它的吸引力在于它的成本效益、低排放、内在安全性和较高的能量密度。因此,高性能水系锌离子电池的设计和改进得到了广泛的研究。在这篇综述中,我们对各种正极的设计策略、电化学性能、挑战和优化进行了分类和比较,包括锰(Mn)基材料和钒(V)基材料。同时,还讨论了提高性能的策略。最后,总结了水系锌离子电池正极面临的挑战,并提出了未来的研究方向。总的来说,文章探索不同的正极为研究人员选择合适的材料以进一步提高水系锌离子电池的性能提供了指导。Aqueous zinc-ion batteries (AZIBs), as a candidate for large-scale electrochemical energy storage solutions in the future, have received extensive attention. Its attraction lie in its cost-effectiveness, low emission, inherent safety, and high energy density. Therefore, the design and improvement of high-performance aqueous zinc-ion batteries have been widely studied. In this review, we classified and compared the design strategies, electrochemical properties, challenges, and optimization of various cathode materials, including manganese (Mn)-based materials and vanadium (V)-based materials. At the same time, the strategy of improving performance is also discussed. Finally, the challenges faced by the positive electrode of aqueous zinc-ion batteries are summarized, and the future research direction is put forward. Generally speaking, this paper explores different positive electrodes and provides guidance for researchers to choose suitable materials to further improve the performance of aqueous zinc-ion batteries.展开更多
利用四(4-磺酸基苯基)甲烷(TSPM)和4,4'-二哌啶(DP),通过分子间氢键相互作用,合成了一种新型有机盐(TSPM-DP),并对其进行了质子导电性的研究。结果表明,该有机盐具有良好的稳定性,并展现出优异的质子导电性,在45˚C、100% RH的条件下...利用四(4-磺酸基苯基)甲烷(TSPM)和4,4'-二哌啶(DP),通过分子间氢键相互作用,合成了一种新型有机盐(TSPM-DP),并对其进行了质子导电性的研究。结果表明,该有机盐具有良好的稳定性,并展现出优异的质子导电性,在45˚C、100% RH的条件下,质子导电率可达4.4 × 10−3 S∙cm−1。同时,这种有机的合成方法简单,结合其较好的质子导电性,使其在燃料电池领域中具有一定的应用前景。A novel type of organic salt (TSPM-DP) was synthesized using tetrakis(4-sulfophenyl)methane (TSPM) and 4,4’-dipiperidine (DP) and explored its proton conduction performance. The results show that the organic salt exhibits good stability and high proton conductivity, and the value can be reached as high as 4.4 × 10−3 S∙cm−1 under 45˚C and 100% RH conditions. Meanwhile, the organic salt is easy to synthesize, combining with the high proton conductivity, it will have a perspective application in fuel-cell technology.展开更多
研发高效的CO2电还原催化剂对减少碳排放、实现碳中和具有重要意义。单一金属催化剂如单原子催化剂因其良好的催化性能在CO2电还原领域得到广泛研究。然而,单一金属催化剂存在活性位点单一、反应动力学慢、产物选择性低和稳定性不足等...研发高效的CO2电还原催化剂对减少碳排放、实现碳中和具有重要意义。单一金属催化剂如单原子催化剂因其良好的催化性能在CO2电还原领域得到广泛研究。然而,单一金属催化剂存在活性位点单一、反应动力学慢、产物选择性低和稳定性不足等缺点。双金属催化剂因其独特的结构和优异的性能而受到极大关注。通过引入另一种金属,可以改变催化剂的电子结构,促进新的活性位点的形成,从而优化中间体与活性位点之间的相互作用。文章从衍生材料的制备策略、双金属材料的优势剂在电催化二氧化碳领域的应用等角度具体阐述了双金属衍生材料在电催化碳还原领域的研究进展。Developing efficient CO2 electroreduction catalysts is of great significance for reducing carbon emissions and achieving carbon neutrality. Single metal catalysts such as single atom catalysts have been widely studied in the field of CO2 electroreduction due to their excellent catalytic performance. However, single metal catalysts have disadvantages such as single active sites, slow reaction kinetics, low product selectivity, and insufficient stability. Bimetallic catalysts have attracted great attention due to their unique structure and excellent performance. By introducing another metal, the electronic structure of the catalyst can be altered, promoting the formation of new active sites and optimizing the interaction between intermediates and active sites. This article presents the research progress of bimetallic-derived materials in the field of electrocatalytic carbon reduction, focusing on the preparation strategies of derived materials and the application of dominant agents of bimetallic materials in the field of electrocatalytic carbon dioxide reduction.展开更多
氮元素广泛存在于自然界中,对人类生产生活和生态系统平衡至关重要。文章主要介绍了硝酸盐、亚硝酸盐、氨氮、氮氧化物、总氮和总凯氏氮等含氮化合物的国家标准及行业标准中主要的检测方法。根据各类检测方法的特性,分析了它们的优劣势...氮元素广泛存在于自然界中,对人类生产生活和生态系统平衡至关重要。文章主要介绍了硝酸盐、亚硝酸盐、氨氮、氮氧化物、总氮和总凯氏氮等含氮化合物的国家标准及行业标准中主要的检测方法。根据各类检测方法的特性,分析了它们的优劣势,并据此提出了部分方法的应用建议,以提升检测准确性和效率。同时,为了响应化工、医药、农业和环境保护等领域对氮元素分析的需求,提出了研发全自动分析仪的构想。文章旨在为同行业的工作者、分析者提供参考和分析,从而使环境检测与保护、人类生产生活等领域的氮元素检测更加高效。Nitrogen is widely present in nature and plays an important role in industrial production, human life, and ecosystem balance. This paper reviews the detection methods in the national standards and industry standards for nitrogen-containing compounds, such as nitrate, nitrite, ammonia nitrogen, nitrogen oxides, total nitrogen, and total Kjeldahl nitrogen. Based on the characteristics of different detection methods, this paper discusses their advantages and defects and gives some suggestions to improve the accuracy and efficiency of the detection for different types of nitrogen. Meanwhile, in order to meet the requirements of nitrogen analysis in the fields of chemical industry, medicine, agriculture, and environmental protection, the conceiving of developing an automatic analyzer was proposed. This review aims to provide a reference for analysts in the field of nitrogen detection so as to make the nitrogen analysis more precise and efficient in various environments.展开更多
三维结构的分子筛既是天然存在的,也可以在实验室中合成。沸石分子筛具有广泛的应用,如环境修复,催化活性,生物技术应用,气体传感和医疗应用。虽然天然分子筛很容易获得,但由于其易于纯相合成,离子交换能力好,尺寸均匀等优点,目前越来...三维结构的分子筛既是天然存在的,也可以在实验室中合成。沸石分子筛具有广泛的应用,如环境修复,催化活性,生物技术应用,气体传感和医疗应用。虽然天然分子筛很容易获得,但由于其易于纯相合成,离子交换能力好,尺寸均匀等优点,目前越来越重视分子筛的合成。近年来,如何从低成本材料合成分子筛,特别是如何解决主要的环境问题,也受到了人们的广泛关注。在不同的合成方法中,水热法被广泛应用于以粉煤灰、稻壳灰、高炉渣和高岭土等廉价原料合成各种分子筛。因此,本文对分子筛合成方法及其在环境工程中的潜在应用进行综述。Molecular sieves with the three-dimensional structures occur naturally or can be synthesized in the laboratory. Zeolites have versatile applications such as environmental remediation, catalytic activity, biotechnological application, gas sensing and medicinal applications. Although, naturally occurring molecular sieves are readily available, nowadays, more emphasis is given on the synthesis of the molecular sieves due to their easy synthesis in the pure form, better ion exchange capabilities and uniform in size. Recently, much attention has also been paid on how molecular sieve is being synthesized from low-cost material, particularly, by resolving the major environmental issues. Among different synthesis methods, hydrothermal method is commonly found to be used widely in the synthesis of various molecular sieves from inexpensive raw materials such as fly ash, rice husk ash, blast furnace slag and kaolin. Hence, the main purpose of this review is to make an effective resolution of molecular sieve synthesis methods together with potential applications in environmental engineering.展开更多
精准鉴定遗传多样性是植物资源利用和深入开展科学研究的基础。本文利用葛属3个种的叶绿体基因组序列中的物种特有的624个核苷酸变异位点作为分子性状,首次编制了分子鉴定检索表,供试样品得到成功鉴定。物种特有变异位点的数量和核苷酸...精准鉴定遗传多样性是植物资源利用和深入开展科学研究的基础。本文利用葛属3个种的叶绿体基因组序列中的物种特有的624个核苷酸变异位点作为分子性状,首次编制了分子鉴定检索表,供试样品得到成功鉴定。物种特有变异位点的数量和核苷酸构成存在种间差异。食用葛的特有变异位点的数量(576)最多,粉葛(38)和葛藤(10)的特有变异位点的数量明显较少。食用葛的特有变异位点中,4类核苷酸的比例由大到小依次为:T (26.91%)、A (26.04%)、C (24.13%)和G (22.92%),差异不大。粉葛的特有变异位点中,T (39.47%)的比例最高,随后依次为C (26.32%)、A (18.42%)和G (15.79%),T的比例是G的比例的约2.5倍。葛藤的特有变异位点数量相对稀少,其中,T的比例(50.00%)最高,是A或G的比例(20.00%)的2.5倍,是C的比例(10.00%)的5倍。结果显示,叶绿体基因组的单核苷酸变异位点信息可用于葛属植物资源遗传多样性的分子鉴定。本文调查了中国过去120多年来葛属植物标本的收集现状,讨论了存在的问题与对策。本研究对于葛属植物的分类修订、种质资源的保护和利用具有重要价值。Accurate identification of genetic diversity is the basis for utilization of plant resources and further scientific research. In this paper, 624 taxon-specific variable nucleotide sites in the complete chloroplast genome of 3 species from the genus Pueraria DC. were used as molecular traits to identify successfully the genetic resources of this plant genus and compile a molecular classification key for the first time. There are differences in aspects of amount and base composition of taxon-specific variable nucleotide sites among the species. The amount of taxon-specific variable nucleotide sites in Pueraria edulis Pamp. (576) is the highest, those in Pueraria montana var. thomsonii (Benth.) M.R. Almeida (38) and Pueraria montana (Lour.) Merr. (10) are significantly fewer. The proportion of T (26.91%), A (26.04%), C (24.13%) and G (22.92%) is decreasing respectively but with small differences among taxon-specific variable nucleotide sites in Pueraria edulis Pamp. The proportion of T (39.47%) is the highest, followed by C (26.32%), A (18.42%) and G (15.79%) in taxon-specific variable nucleotide sites in Pueraria montana var. thomsonii, the proportion of T is 2.5 times that of G. Relatively, the amount of taxon-specific variable nucleotide sites is fewer in Pueraria montana, where the proportion of T (50.00%) is the highest, being 2.5 times that (20.00%) of A or G, and 5 times that (10.00%) of C. Our results indicated that taxon-specific variable nucleotide sites from the chloroplast genomes could be used for the molecular classification of the genetic diversity in the genus Pueraria resources. In this paper, the status of Pueraria plant specimens collected in the past 120 years in China is investigated and problems and possible strategies are discussed. This study is valuable for taxonomic revision, conservation and utilization of Pueraria plant germplasm resources.展开更多
以碳酸钙、氧化铝和氧化硅为原料,通过高温烧结法制备钙铝黄长石晶体。采用TG-DSC、XRD、SEM和TEM探究了煅烧温度对钙铝黄长石合成的影响;利用静态浸出实验检测了钙铝黄长石的供碱释钙能力,并将其用于废水中PO43−和Cd2+的吸附去除。结...以碳酸钙、氧化铝和氧化硅为原料,通过高温烧结法制备钙铝黄长石晶体。采用TG-DSC、XRD、SEM和TEM探究了煅烧温度对钙铝黄长石合成的影响;利用静态浸出实验检测了钙铝黄长石的供碱释钙能力,并将其用于废水中PO43−和Cd2+的吸附去除。结果表明:四方短柱状钙铝黄长石晶体可在1400℃下经固相反应合成,硅灰石、硅酸二钙和铝酸钙是其合成的中间产物,并且高温下液相的形成和饱和析晶是其主要形成机制。20 g/L的投加量下,钙铝黄长石可向水溶液中释放252.91 mg/L的Ca2+,并将溶液pH提升至9.1,具有良好的供碱释钙能力。钙铝黄长石可以作为理想的水处理用吸附剂,对初始浓度为50 mg/L的PO43−去除率达到99.25%,对初始浓度为20 mg/L的Cd2+去除率达到83.26%。Calcium carbonate, silica and alumina were used as raw materials to prepare gehlenite by sintering. The influence of sintering temperature on the synthesis of gehlenite was analyzed by TG-DSC, XRD, SEM and TEM. The alkali and calcium releasing capacity of gehlenite was tested by static leaching experiment. Gehlenite was also used to remove PO43−and Cd2+ from aqueous solutions by adsorption. The results showed that gehlenite crystals were tetragonal short columnar and could be synthesized by solid phase reaction at 1400˚C. Wollastonite, larnite and calcium aluminate were generated as intermediates for gehlenite. The formation of liquid phase and saturation crystallization at high temperature were the main formation mechanisms of gehlenite. At the dosage of 20 g/L, gehlenite could release 252.91 mg/L of Ca2+, and increase the solution pH to 9.1, which had a good alkali and calcium releasing capacity. Moreover, the removal efficiency of PO43−(50 mg/L) and Cd2+ (20 mg/L) reached 99.25% and 83.26%, respectively, so gehlenite was an ideal adsorbent for wastewater treatment.展开更多
DNA浓度测量在分子生物学中具有重要的应用价值。传统的基于吸光度法测量灵敏度低,需要试剂量大,为解决该问题,本文构建了基于荧光检测的高灵敏度微型DNA浓度测量系统。选取光源为中心波长505 nm激光模组,通过将SYBR Green I染料与DNA混...DNA浓度测量在分子生物学中具有重要的应用价值。传统的基于吸光度法测量灵敏度低,需要试剂量大,为解决该问题,本文构建了基于荧光检测的高灵敏度微型DNA浓度测量系统。选取光源为中心波长505 nm激光模组,通过将SYBR Green I染料与DNA混合,研究了荧光强度与DNA浓度之间的量化关系。结果表明,DNA浓度在1~16 ng/μL范围内,与其荧光强度呈线性关系,相关系统高达0.994。本研究为小型DNA浓度测量系统的开发奠定了实验基础。展开更多
本研究对多巴胺(DA)进行光电化学检测,通过制备二氧化硅悬浮液(SiO2)、还原氧化石墨烯(rGO)、溴氧化铋(BiOBr)三种材料进而制备SiO2@BiOBr/rGO复合材料并构筑光电化学传感器,SiO2@BiOBr/rGO在有光时检测多巴胺时有显著的光电流响应。石...本研究对多巴胺(DA)进行光电化学检测,通过制备二氧化硅悬浮液(SiO2)、还原氧化石墨烯(rGO)、溴氧化铋(BiOBr)三种材料进而制备SiO2@BiOBr/rGO复合材料并构筑光电化学传感器,SiO2@BiOBr/rGO在有光时检测多巴胺时有显著的光电流响应。石墨烯具有优异的导电性和显著的机械强度。二氧化硅(SiO2)是一种成本低、高生物相容性、热稳定性、透光性能好、带隙窄的材料。BiOBr作为一种典型的半导体光电材料,拥有独特的层状四方结构,花状BiOBr由层状结构组成,有利于进一步抑制空穴–电荷重组,可提高其光电性能。该光电传感器检测多巴胺时的浓度范围为2~300 μmol/L,检出限为0.67 μmol/L,表明传感器对多巴胺有较好的检测效果。该SiO2@BiOBr/rGO光电化学传感器具有稳定性好、灵敏度高等优点,对多巴胺的检测具有重要的意义,希望其在监测细胞内多巴胺浓度水平方面具有广阔的应用前景。This study aimed to prepare SiO2@BiOBr/rGO composite materials by combining SiO2 suspension, reduced graphene oxide (rGO), and bismuth oxybromide (BiOBr) for the construction of relevant photoelectrochemical sensors to detect dopamine (DA). Under visible light irradiation, SiO2@BiOBr/ rGO exhibited a significant photocurrent response during dopamine detection. Graphene has excellent electrical conductivity and remarkable mechanical strength. SiO2 has low production cost, high biocompatibility, thermal stability, good transparency, and a narrow-forbidden bandgap. As a typical semiconductor photoelectric material, BiOBr has a unique layered tetragonal structure. Flower-like BiOBr is composed of layered structures, which is conducive to further suppressing hole-charge recombination and improving its photoelectric performance. The concentration range of dopamine detected by this photoelectric sensor was 2~300 μmol/L, with a detection limit of 0.67 μmol/L, indicating that the sensor had a good detection effect on dopamine. This SiO2@BiOBr/rGO photoelectrochemical sensor has the advantages of good stability, high sensitivity and so on, and is of great significance for the detection of dopamine. It is expected to have broad application prospects in monitoring intracellular dopamine concentration levels.展开更多
文摘文章建立了自动电位滴定法测定有机肥料中有机质的方法。确定了滴定的加液步长为0.05 mL,等当点识别标准为100 mV,在此条件下可获得圆滑的滴定曲线和准确的滴定结果。进行不同含量的有机肥标准样品的精密度及准确度考察,结果显示,相对标准偏差在0.46%~0.81%之间,相对误差在−1.29%~3.3%之间,且测定结果均在标准值的不确定度范围之内。通过与经典滴定法的比对试验并对试验结果进行t检验及F检验,各试验组的t值均小于t (0.05, 2n-2)值,F值小于对应的临界值,即方法之间的准确度及精密度不存在显著性差异。建立的方法具有操作简便、准确可靠、重复性好、效率高等优点,适用于有机肥料中有机质含量的测定。A method for determining organic matter in organic fertilizers using automatic potentiometric titration has been established. The addition step size for titration has been determined to be 0.05 mL, and the identification standard for equivalent points is 100 mV. Under these conditions, a smooth titration curve and accurate titration results can be obtained. The precision and accuracy of organic fertilizer standard samples with different contents were investigated, and the results showed that the relative standard deviation was from 0.46% to 0.81%, and the relative error was from 0.3% to 3.3%. The measurement results were all within the uncertainty range of the standard values. Through the t-tests and F-tests, it was found that the t-values of each experimental group were less than the t (0.05, 2n-2) value, and the F-values were also less than the corresponding critical values, indicating that there was no significant difference in accuracy and precision between the methods. The method has the advantages of simple operation, accuracy and reliability, good repeatability, and high efficiency, and is suitable for the determination of organic matter content in organic fertilizers.
文摘医用导管作为现代医疗中不可或缺的重要设备,广泛应用于药物输送、体液引流和病症诊疗等领域。其性能的优劣直接影响诊疗效果和患者的生命安全,而导管的材料和表面涂层的选择,则在改善其生物相容性、耐久性及抗菌性能方面起着至关重要的作用。文章系统性地综述了当前医用导管表面改性技术的研究进展,包括水凝胶涂层、润滑液体注入多孔表面、静电纺丝、沉积法以及等离子体处理法等。这些技术通过优化涂层的材料成分和微观结构,不仅显著提升了导管的抗菌性能、抗血栓能力和机械强度,还赋予其药物缓释、智能响应等多样化功能,为复杂医疗环境中的导管应用提供了重要解决方案。展望未来,生物可降解材料、纳米技术的引入以及材料科学与生物医学等多学科的深度融合,将为医用导管涂层的创新设计与临床转化提供强大动力,进一步推动其在精准医疗领域的广泛应用。Medical catheters, as indispensable devices in modern healthcare, are widely used in drug delivery, fluid drainage, and disease diagnosis and treatment. Their performance directly influences therapeutic outcomes and patient safety. The selection of catheter materials and surface coatings plays a critical role in improving biocompatibility, durability, and antibacterial properties. This paper systematically reviews the current advancements in medical catheter surface modification technologies, including hydrogel coatings, lubricated liquid-infused porous surfaces, electrospinning, deposition methods, and plasma treatment. These technologies optimize the material composition and microstructure of coatings, significantly enhancing the antibacterial properties, thrombus resistance, and mechanical strength of catheters. Furthermore, they endow catheters with diverse functionalities, such as drug release and intelligent responsiveness, providing crucial solutions for catheter applications in complex medical environments. Looking to the future, the incorporation of biodegradable materials, nanotechnology, and the deep integration of materials science and biomedicine will drive innovative designs and clinical translation of catheter coatings, further advancing their applications in the field of precision medicine.
文摘硅基锂离子电池负极材料由于能量密度高、工作电压适中而受到全世界的关注,但硅基材料存在体积膨胀和动力学较差等缺陷,该问题严重限制了硅基负极材料的大规模应用。文章提出了一种将纳米尺寸的介孔Si颗粒封装在碳中的设计策略,该Si@C纳米复合材料的尺寸约为200 nm左右。将Si@C以不同比例(20 wt%、30 wt%、40 wt%)和石墨混合、球磨合成,从而最终制备得到硅–石墨锂离子电池负极材料,通过包覆的碳层和复合的石墨层提高LIBs的能量密度和高稳定性。在本工作的研究中我们发现Si@C/G (20 wt%)纳米复合材料在100次循环中表现出600 mAh∙g−1的高比容量,在0.5 A∙g−1的电流密度下实现了750次的稳定循环,展现了优秀的循环稳定性,平均充电/放电容量为360 mAh∙g−1。此外,在不同电流密度下测试了Si@C/G (20 wt%)复合电极,并在1 A∙g−1下显示出262 mAhg−1的相对较高的可逆容量。与其他两种复合材料相比,Si@C/G (20 wt%)表现出高容量和稳定性。Si@C/G (20 wt%)获得的电化学性能证明了低含量合成纳米硅与石墨的高兼容性。此外,碳涂层防止了充电/放电过程中Si的体积膨胀。这个想法可以应用于设计高能量密度LIB负极材料。Silicon-based anodes for lithium-ion batteries (LIBs) are attractive due to their high energy density, but challenges such as significant volume expansion and poor kinetics have limited their practical application. This work introduces a Si@C nanocomposite, where nano-sized mesoporous silicon particles are encapsulated in carbon, with particle sizes around 200nm. The Si@C was blended with graphite at ratios of 20 wt%, 30 wt%, and 40 wt%, then ball-milled to form composite anode materials. The Si@C/G (20 wt%) composite demonstrated superior electrochemical performance, maintaining a high specific capacity of 600 mAh∙g⁻¹ over 100 cycles and stable cycling up to 750 times at 0.5 A∙g⁻¹, with an average charge/discharge capacity of 360 mAh∙g⁻¹. At higher current densities, it showed good reversible capacity retention, reaching 262 mAh∙g⁻¹ at 1 A∙g⁻¹. The carbon coating effectively mitigated silicon’s volumetric changes during cycling, enhancing stability. This study highlights the effectiveness of integrating low-content nano-silicon with graphite for achieving high-performance LIB anodes, showcasing the potential of Si@C/G (20 wt%) composites for next-generation battery technology. Moreover, the carbon coating prevented the volume expansion of Si during the charge/discharge process. This concept can be applied in designing high-energy-density LIB anode materials.
文摘目的:测定不同产地黑种草子挥发油中百里醌的含量。方法:将5种不同产地的黑种草子用两种不同化学提取方法提取挥发油,建立定量核磁共振波谱法测定挥发油中的百里醌。使用500 MHZ Bruker Avance III (TMS, δ = 0 ppm)核磁共振谱仪,以氖代氯仿为溶剂,在测定温度25℃、延迟时间2 s和扫描次数64的条件下扫描,通过化学移位及峰面积归一化法测定各黑种草子挥发油中百里醌相对百分比含量。结果:以化学位移在δ = 6.5 ppm与δ = 6.6 ppm处的百里醌的氢质子峰作为定量峰,其峰面积比与其质量比的线性回归方程为Y = 0.493x − 0.0005,相关系数为0.999。5种不同产地黑种草子挥发油中百里醌在方法1中测得USA1 (0.065%)、USA2 (0.093%)、USA3 (0.043%)、Tibe (0.043%)、Guangxi (0.062%)。在方法2中测得USA1 (0.263%)、USA2 (0.153%)、USA3 (0.037%)、Tibet (0.200%)、Guangxi (0.224%)。结论:分析结果表明,因产地及提取方法差异,黑种草子挥发油中百里醌含量测定是有差异的。文章通过测定不同产地黑种草子挥发油中的百里醌含量,为进一步研究开发黑种草子的药用价值奠定基础。Objective: To determine the content of quinone in volatile oil from black seed (Nigella) of different habitats. Methods: The essential oils were extracted from the seeds of black grass from five different habitats by two different chemical extraction methods, and the thymoquinone in the essential oils was determined by quantitative nuclear magnetic resonance spectroscopy. A 500 MHz Bruker Avance III (TMS, δ = 0 ppm) nuclear magnetic resonance spectrometer was used, with deuterochloroform as the solvent, at a measurement temperature of 25˚C, a delay time of 2 seconds, and 64 scans, to determine the relative percentage content of thymoquinone in the volatile oils of black grass seeds by chemical shift and peak area normalization. Results: Using the hydrogen proton peak of thymoquinone with a chemical shift at δ = 6.5 ppm and δ = 6.6 ppm as the quantitative peak, the peak area ratio of thymoquinone and its mass ratio were linear regression equation Y = 0.493x − 0.0005, the correlation coefficient was 0.999, and thymoquinone in volatile oils of black grass from five different habitats was determined as USA1 (0.065%), USA2 (0.093%), USA3 (0.043%), Tibet (0.043%), Guangxi (0.062%) in method 1. In method 2, USA1 (0.263%), USA2 (0.153%), USA3 (0.037%), Tibet (0.200%), and Guangxi (0.224%) were measured. Conclusion: The results showed that there were differences in the determination of thymoquinone content in the essential oil of Herba Nigella due to the differences in origin and extraction methods. In this paper, the content of thymoquinone in the essential oil of black seed grass from different habitats was determined to lay a foundation for further research and development of the medicinal value of black seed grass.
文摘焦化废水具有高浓度、成分复杂、生物毒性高等特点,采用常规处理方式处理焦化废水具有很大的挑战性。与传统生物法、电化学相比,生物电化学系统(Bioelectrochemical System, BES)不仅具有同时去除焦化废水中碳质和氮质污染物的能力,而且可以通过电强化微生物的协同作用,节省整个处理过程的能量消耗。但是,鲜有综述对生物电化学系统在处理焦化废水中的研究进行系统总结。因此,文章在回顾BES原理、类型、电极材料的基础上,总结了BES在焦化废水处理中的研究进展,并分析了其在去除有机污染物、氨氮等污染物方面的强化效果。通过这些系统的回顾,本综述不仅阐述了电强化微生物促进焦化废水中污染物的作用机理,提出了未来关于BES的研究方向,还展望了BES用于焦化废水处理的前景和挑战,从而促进了BES在焦化废水处理中的实际应用。Coking wastewater is characterized by high concentrations, complex composition, and high biological toxicity, making its treatment challenging using conventional methods. Compared to traditional biological and electrochemical processes, the Bioelectrochemical System (BES) not only have the capability to simultaneously remove carbon and nitrogen pollutants from coking wastewater but also enhance microbial activity through electrical stimulation, thereby reducing energy consumption in the treatment process. However, there is a lack of systematic reviews summarizing the research on BES in coking wastewater treatment. This paper reviews the principles, types, and electrode materials of BES, summarizes the research progress of BES in coking wastewater treatment, and analyzes its enhanced effects in removing organic pollutants and ammonia nitrogen. Through this systematic review, the mechanisms by which electrostimulation promotes pollutant removal in coking wastewater are elucidated, future research directions for BES are proposed, and the prospects and challenges of using BES for coking wastewater treatment are discussed, thereby facilitating the practical application of BES in this field.
文摘柱芳烃是一类具有独特对称性和柱状空腔结构的新型人工合成大环分子,可通过简单的化学方法对其端基进行功能化修饰,目前已发展成为一类重要的大环基元分子用于构筑各种刺激响应的功能超分子组装材料。光是一种清洁、非侵入性和时空可控的外部刺激,具有光刺激响应特性的主–客体作用超分子体系受到广泛关注。文章总结了近年来在基于柱芳烃的光响应主–客体超分子组装体系和功能材料方面的重要研究进展,系统阐述了目前报道的光响应柱芳烃主–客体超分子组装体系的主要构筑策略和代表性应用。Pillar[n]arenes are a class of artificial synthetic macrocyclic molecules featuring unique symmetrical and pillar-shaped cavity structures, as well as facile functionalization by chemically modifying their end groups. These features have conferred pillar[n]arenes to be of fundamental importance as macrocyclic building blocks for the construction of copious stimuli-responsive functional supramolecular assembly systems and materials. Light represents a clean and noninvasive external stimulus with unique spatiotemporal controllability, which has attracted considerable attention to the development of photoresponsive host-vip supramolecular systems. This review mainly summarizes the recent progress on photoresponsive pillar[n]arene-based host-vip supramolecular assembly systems and functional materials, with systematical elaboration and perspectives on their construction strategies and applications of currently reported photoresponsive pillar[n]arene-based host-vip supramolecular assembly systems and materials.
文摘共价有机骨架(COFs)是一类由共价键周期性连接的有机组分组成的晶态多孔有机聚合物。COFs材料通常因其本身所具有的大Π电子共轭体系表现出许多突出的特性,如高比表面积和孔隙率、高化学稳定性和热稳定性,对合成单体的不同选择使其结构易调控。这些特殊的优势使COFs材料在光催化方面表现出卓越的性能。此外,通过离子掺杂可以显著提高COFs材料作为光催化剂的活性。文章综述了离子型COF基材料在光催化体系中的最新研究进展。首先,对离子型COFs (iCOFs)的制备方法进行了分析和比较。此外,还介绍了离子型COFs基材料光催化反应的基本原理以及光催化领域的最新研究进展。Covalent Organic Frameworks (COFs) are crystalline porous organic polymer composed of organic components periodically linked by covalent bonds. COF materials usually exhibit many outstanding properties due to their large Π electron-conjugated system, such as high specific surface area and porosity, high chemical stability, and thermal stability, and the different selections of synthetic monomers make their structures easy to regulate. These special advantages make COFs materials show remarkable performance in photocatalysis. In addition, the activity of COFs as photocatalysts can be significantly improved by ion doping. The recent progress of research on ionic COF-based materials in photocatalytic systems is reviewed in this paper. Firstly, the preparation methods of ionic COFs (iCOFs) were analyzed and compared. In addition, the basic principle of photocatalytic reaction of ionic COFs-based materials and the latest research progress in the field of photocatalysis are also reviewed.
文摘近年来,水资源短缺问题越来越严重,基于吸附的大气水收集被认为是一种有效应对水资源短缺的新兴技术。共价有机框架结构(COFs)是一类新型的多孔结晶聚合物,由于其独特的结构特性使其能在气体存储与分离、催化、光电材料、及大气水收集等领域展现出广阔的应用前景。文章综述了COFs在大气水收集中的应用研究,简单介绍了大气水收集技术及在基于吸附的大气水收集(Sorption-Based Atmospheric Water Harvesting, SAWH)领域应用的COFs。In recent years, water scarcity has become an increasingly pressing issue. One effective approach to addressing the imminent water shortage crisis is sorption-based atmospheric water harvesting (SAWH). Covalent organic frameworks (COFs) are a type of porous crystalline material. Due to its unique structural characteristics, it can show broad application prospects in the fields of gas storage and separation, catalysis, optoelectronic materials, and atmospheric water harvesting. Then, we summarize recent advances in using COF-based sorbents for atmospheric water harvesting and briefly introduce the technology of atmospheric water collection and the application of COFs in the field of sorption-based atmospheric water harvesting (SAWH).
文摘水系锌离子电池(AZIBs)作为未来大规模电化学储能解决方案的候选者,已经获得了广泛的关注。它的吸引力在于它的成本效益、低排放、内在安全性和较高的能量密度。因此,高性能水系锌离子电池的设计和改进得到了广泛的研究。在这篇综述中,我们对各种正极的设计策略、电化学性能、挑战和优化进行了分类和比较,包括锰(Mn)基材料和钒(V)基材料。同时,还讨论了提高性能的策略。最后,总结了水系锌离子电池正极面临的挑战,并提出了未来的研究方向。总的来说,文章探索不同的正极为研究人员选择合适的材料以进一步提高水系锌离子电池的性能提供了指导。Aqueous zinc-ion batteries (AZIBs), as a candidate for large-scale electrochemical energy storage solutions in the future, have received extensive attention. Its attraction lie in its cost-effectiveness, low emission, inherent safety, and high energy density. Therefore, the design and improvement of high-performance aqueous zinc-ion batteries have been widely studied. In this review, we classified and compared the design strategies, electrochemical properties, challenges, and optimization of various cathode materials, including manganese (Mn)-based materials and vanadium (V)-based materials. At the same time, the strategy of improving performance is also discussed. Finally, the challenges faced by the positive electrode of aqueous zinc-ion batteries are summarized, and the future research direction is put forward. Generally speaking, this paper explores different positive electrodes and provides guidance for researchers to choose suitable materials to further improve the performance of aqueous zinc-ion batteries.
文摘利用四(4-磺酸基苯基)甲烷(TSPM)和4,4'-二哌啶(DP),通过分子间氢键相互作用,合成了一种新型有机盐(TSPM-DP),并对其进行了质子导电性的研究。结果表明,该有机盐具有良好的稳定性,并展现出优异的质子导电性,在45˚C、100% RH的条件下,质子导电率可达4.4 × 10−3 S∙cm−1。同时,这种有机的合成方法简单,结合其较好的质子导电性,使其在燃料电池领域中具有一定的应用前景。A novel type of organic salt (TSPM-DP) was synthesized using tetrakis(4-sulfophenyl)methane (TSPM) and 4,4’-dipiperidine (DP) and explored its proton conduction performance. The results show that the organic salt exhibits good stability and high proton conductivity, and the value can be reached as high as 4.4 × 10−3 S∙cm−1 under 45˚C and 100% RH conditions. Meanwhile, the organic salt is easy to synthesize, combining with the high proton conductivity, it will have a perspective application in fuel-cell technology.
文摘研发高效的CO2电还原催化剂对减少碳排放、实现碳中和具有重要意义。单一金属催化剂如单原子催化剂因其良好的催化性能在CO2电还原领域得到广泛研究。然而,单一金属催化剂存在活性位点单一、反应动力学慢、产物选择性低和稳定性不足等缺点。双金属催化剂因其独特的结构和优异的性能而受到极大关注。通过引入另一种金属,可以改变催化剂的电子结构,促进新的活性位点的形成,从而优化中间体与活性位点之间的相互作用。文章从衍生材料的制备策略、双金属材料的优势剂在电催化二氧化碳领域的应用等角度具体阐述了双金属衍生材料在电催化碳还原领域的研究进展。Developing efficient CO2 electroreduction catalysts is of great significance for reducing carbon emissions and achieving carbon neutrality. Single metal catalysts such as single atom catalysts have been widely studied in the field of CO2 electroreduction due to their excellent catalytic performance. However, single metal catalysts have disadvantages such as single active sites, slow reaction kinetics, low product selectivity, and insufficient stability. Bimetallic catalysts have attracted great attention due to their unique structure and excellent performance. By introducing another metal, the electronic structure of the catalyst can be altered, promoting the formation of new active sites and optimizing the interaction between intermediates and active sites. This article presents the research progress of bimetallic-derived materials in the field of electrocatalytic carbon reduction, focusing on the preparation strategies of derived materials and the application of dominant agents of bimetallic materials in the field of electrocatalytic carbon dioxide reduction.
文摘氮元素广泛存在于自然界中,对人类生产生活和生态系统平衡至关重要。文章主要介绍了硝酸盐、亚硝酸盐、氨氮、氮氧化物、总氮和总凯氏氮等含氮化合物的国家标准及行业标准中主要的检测方法。根据各类检测方法的特性,分析了它们的优劣势,并据此提出了部分方法的应用建议,以提升检测准确性和效率。同时,为了响应化工、医药、农业和环境保护等领域对氮元素分析的需求,提出了研发全自动分析仪的构想。文章旨在为同行业的工作者、分析者提供参考和分析,从而使环境检测与保护、人类生产生活等领域的氮元素检测更加高效。Nitrogen is widely present in nature and plays an important role in industrial production, human life, and ecosystem balance. This paper reviews the detection methods in the national standards and industry standards for nitrogen-containing compounds, such as nitrate, nitrite, ammonia nitrogen, nitrogen oxides, total nitrogen, and total Kjeldahl nitrogen. Based on the characteristics of different detection methods, this paper discusses their advantages and defects and gives some suggestions to improve the accuracy and efficiency of the detection for different types of nitrogen. Meanwhile, in order to meet the requirements of nitrogen analysis in the fields of chemical industry, medicine, agriculture, and environmental protection, the conceiving of developing an automatic analyzer was proposed. This review aims to provide a reference for analysts in the field of nitrogen detection so as to make the nitrogen analysis more precise and efficient in various environments.
文摘三维结构的分子筛既是天然存在的,也可以在实验室中合成。沸石分子筛具有广泛的应用,如环境修复,催化活性,生物技术应用,气体传感和医疗应用。虽然天然分子筛很容易获得,但由于其易于纯相合成,离子交换能力好,尺寸均匀等优点,目前越来越重视分子筛的合成。近年来,如何从低成本材料合成分子筛,特别是如何解决主要的环境问题,也受到了人们的广泛关注。在不同的合成方法中,水热法被广泛应用于以粉煤灰、稻壳灰、高炉渣和高岭土等廉价原料合成各种分子筛。因此,本文对分子筛合成方法及其在环境工程中的潜在应用进行综述。Molecular sieves with the three-dimensional structures occur naturally or can be synthesized in the laboratory. Zeolites have versatile applications such as environmental remediation, catalytic activity, biotechnological application, gas sensing and medicinal applications. Although, naturally occurring molecular sieves are readily available, nowadays, more emphasis is given on the synthesis of the molecular sieves due to their easy synthesis in the pure form, better ion exchange capabilities and uniform in size. Recently, much attention has also been paid on how molecular sieve is being synthesized from low-cost material, particularly, by resolving the major environmental issues. Among different synthesis methods, hydrothermal method is commonly found to be used widely in the synthesis of various molecular sieves from inexpensive raw materials such as fly ash, rice husk ash, blast furnace slag and kaolin. Hence, the main purpose of this review is to make an effective resolution of molecular sieve synthesis methods together with potential applications in environmental engineering.
文摘精准鉴定遗传多样性是植物资源利用和深入开展科学研究的基础。本文利用葛属3个种的叶绿体基因组序列中的物种特有的624个核苷酸变异位点作为分子性状,首次编制了分子鉴定检索表,供试样品得到成功鉴定。物种特有变异位点的数量和核苷酸构成存在种间差异。食用葛的特有变异位点的数量(576)最多,粉葛(38)和葛藤(10)的特有变异位点的数量明显较少。食用葛的特有变异位点中,4类核苷酸的比例由大到小依次为:T (26.91%)、A (26.04%)、C (24.13%)和G (22.92%),差异不大。粉葛的特有变异位点中,T (39.47%)的比例最高,随后依次为C (26.32%)、A (18.42%)和G (15.79%),T的比例是G的比例的约2.5倍。葛藤的特有变异位点数量相对稀少,其中,T的比例(50.00%)最高,是A或G的比例(20.00%)的2.5倍,是C的比例(10.00%)的5倍。结果显示,叶绿体基因组的单核苷酸变异位点信息可用于葛属植物资源遗传多样性的分子鉴定。本文调查了中国过去120多年来葛属植物标本的收集现状,讨论了存在的问题与对策。本研究对于葛属植物的分类修订、种质资源的保护和利用具有重要价值。Accurate identification of genetic diversity is the basis for utilization of plant resources and further scientific research. In this paper, 624 taxon-specific variable nucleotide sites in the complete chloroplast genome of 3 species from the genus Pueraria DC. were used as molecular traits to identify successfully the genetic resources of this plant genus and compile a molecular classification key for the first time. There are differences in aspects of amount and base composition of taxon-specific variable nucleotide sites among the species. The amount of taxon-specific variable nucleotide sites in Pueraria edulis Pamp. (576) is the highest, those in Pueraria montana var. thomsonii (Benth.) M.R. Almeida (38) and Pueraria montana (Lour.) Merr. (10) are significantly fewer. The proportion of T (26.91%), A (26.04%), C (24.13%) and G (22.92%) is decreasing respectively but with small differences among taxon-specific variable nucleotide sites in Pueraria edulis Pamp. The proportion of T (39.47%) is the highest, followed by C (26.32%), A (18.42%) and G (15.79%) in taxon-specific variable nucleotide sites in Pueraria montana var. thomsonii, the proportion of T is 2.5 times that of G. Relatively, the amount of taxon-specific variable nucleotide sites is fewer in Pueraria montana, where the proportion of T (50.00%) is the highest, being 2.5 times that (20.00%) of A or G, and 5 times that (10.00%) of C. Our results indicated that taxon-specific variable nucleotide sites from the chloroplast genomes could be used for the molecular classification of the genetic diversity in the genus Pueraria resources. In this paper, the status of Pueraria plant specimens collected in the past 120 years in China is investigated and problems and possible strategies are discussed. This study is valuable for taxonomic revision, conservation and utilization of Pueraria plant germplasm resources.
文摘以碳酸钙、氧化铝和氧化硅为原料,通过高温烧结法制备钙铝黄长石晶体。采用TG-DSC、XRD、SEM和TEM探究了煅烧温度对钙铝黄长石合成的影响;利用静态浸出实验检测了钙铝黄长石的供碱释钙能力,并将其用于废水中PO43−和Cd2+的吸附去除。结果表明:四方短柱状钙铝黄长石晶体可在1400℃下经固相反应合成,硅灰石、硅酸二钙和铝酸钙是其合成的中间产物,并且高温下液相的形成和饱和析晶是其主要形成机制。20 g/L的投加量下,钙铝黄长石可向水溶液中释放252.91 mg/L的Ca2+,并将溶液pH提升至9.1,具有良好的供碱释钙能力。钙铝黄长石可以作为理想的水处理用吸附剂,对初始浓度为50 mg/L的PO43−去除率达到99.25%,对初始浓度为20 mg/L的Cd2+去除率达到83.26%。Calcium carbonate, silica and alumina were used as raw materials to prepare gehlenite by sintering. The influence of sintering temperature on the synthesis of gehlenite was analyzed by TG-DSC, XRD, SEM and TEM. The alkali and calcium releasing capacity of gehlenite was tested by static leaching experiment. Gehlenite was also used to remove PO43−and Cd2+ from aqueous solutions by adsorption. The results showed that gehlenite crystals were tetragonal short columnar and could be synthesized by solid phase reaction at 1400˚C. Wollastonite, larnite and calcium aluminate were generated as intermediates for gehlenite. The formation of liquid phase and saturation crystallization at high temperature were the main formation mechanisms of gehlenite. At the dosage of 20 g/L, gehlenite could release 252.91 mg/L of Ca2+, and increase the solution pH to 9.1, which had a good alkali and calcium releasing capacity. Moreover, the removal efficiency of PO43−(50 mg/L) and Cd2+ (20 mg/L) reached 99.25% and 83.26%, respectively, so gehlenite was an ideal adsorbent for wastewater treatment.
文摘DNA浓度测量在分子生物学中具有重要的应用价值。传统的基于吸光度法测量灵敏度低,需要试剂量大,为解决该问题,本文构建了基于荧光检测的高灵敏度微型DNA浓度测量系统。选取光源为中心波长505 nm激光模组,通过将SYBR Green I染料与DNA混合,研究了荧光强度与DNA浓度之间的量化关系。结果表明,DNA浓度在1~16 ng/μL范围内,与其荧光强度呈线性关系,相关系统高达0.994。本研究为小型DNA浓度测量系统的开发奠定了实验基础。
文摘本研究对多巴胺(DA)进行光电化学检测,通过制备二氧化硅悬浮液(SiO2)、还原氧化石墨烯(rGO)、溴氧化铋(BiOBr)三种材料进而制备SiO2@BiOBr/rGO复合材料并构筑光电化学传感器,SiO2@BiOBr/rGO在有光时检测多巴胺时有显著的光电流响应。石墨烯具有优异的导电性和显著的机械强度。二氧化硅(SiO2)是一种成本低、高生物相容性、热稳定性、透光性能好、带隙窄的材料。BiOBr作为一种典型的半导体光电材料,拥有独特的层状四方结构,花状BiOBr由层状结构组成,有利于进一步抑制空穴–电荷重组,可提高其光电性能。该光电传感器检测多巴胺时的浓度范围为2~300 μmol/L,检出限为0.67 μmol/L,表明传感器对多巴胺有较好的检测效果。该SiO2@BiOBr/rGO光电化学传感器具有稳定性好、灵敏度高等优点,对多巴胺的检测具有重要的意义,希望其在监测细胞内多巴胺浓度水平方面具有广阔的应用前景。This study aimed to prepare SiO2@BiOBr/rGO composite materials by combining SiO2 suspension, reduced graphene oxide (rGO), and bismuth oxybromide (BiOBr) for the construction of relevant photoelectrochemical sensors to detect dopamine (DA). Under visible light irradiation, SiO2@BiOBr/ rGO exhibited a significant photocurrent response during dopamine detection. Graphene has excellent electrical conductivity and remarkable mechanical strength. SiO2 has low production cost, high biocompatibility, thermal stability, good transparency, and a narrow-forbidden bandgap. As a typical semiconductor photoelectric material, BiOBr has a unique layered tetragonal structure. Flower-like BiOBr is composed of layered structures, which is conducive to further suppressing hole-charge recombination and improving its photoelectric performance. The concentration range of dopamine detected by this photoelectric sensor was 2~300 μmol/L, with a detection limit of 0.67 μmol/L, indicating that the sensor had a good detection effect on dopamine. This SiO2@BiOBr/rGO photoelectrochemical sensor has the advantages of good stability, high sensitivity and so on, and is of great significance for the detection of dopamine. It is expected to have broad application prospects in monitoring intracellular dopamine concentration levels.
