生物光化学

生物光化学研究光在动植物体内所引起的生化现象。例如:经过各种不同波长的光辐照后的生命现象,生长规律,某些生理和病理过程,疾病的产生和治疗机理,细胞的辐射损伤和自然防御,以及光合色素在生物进化中的作用等。本文就光引起的现象:视觉、生物钟(光周期性)、植物的光合作用、辐射损伤及其修复、牛皮癣的治疗、新生儿黄疸病的治疗机理,以及光合色素——藻胆蛋白等七种现象,做了综述性的介绍。     

Environmentally Friendly Techniques and Their Comparison in the Extraction of Natural Antioxidants from Green Tea,Rosemary, Clove,and Oregano

Many current food and health trends demand the use of more ecological, sustainable, and environmentally friendly techniques for the extraction of bioactive compounds, including antioxidants. However, extraction yields and final antioxidant activities vary between sources and are highly influenced by the given extraction method and nature and ratio of the employed solvent, especially for total polyphenols, flavonoids, and anthocyanins, which are well recognized as natural antioxidants with food applications. This review focused on the most common extraction techniques and potential antioxidant activity in the food industry for various natural antioxidant sources, such as green tea, rosemary, clove, and oregano. Green extraction techniques have been proven to be far more efficient, environmentally friendly, and economical. In general, these techniques include the use of microwaves, ultrasound, high hydrostatic pressure, pulsed electric fields, enzymes, and deep eutectic solvents, among others. These extraction methods are described here, including their advantages, disadvantages, and applications.     

宝日希勒褐煤在合成气与复合溶剂系统下的液化性能研究

在合成气（CO+H₂）与复合溶剂（水+有机溶剂）液化系统下研究了气氛、温度、催化剂类型对宝日希勒褐煤转化率、油气水产率和CO转化率等液化特征的影响,从而探讨其液化性能。结果表明,在高含水复合溶剂系统中,合成气气氛、反应温度430-450℃适宜宝日希勒褐煤液化转化,转化率可达到81.15%,油气水产率达到71.53%。该液化系统下,含铁、碱和硫复合型催化剂能有效地提高液化转化率和油气水产率,在430℃催化液化下褐煤转化率达92.27%,油气水产率达79.39%。该催化剂有效促进了煤中大分子的裂解和系统中水煤气变换反应进程,沥青质减少,油含量增多。液化油中多环芳烃衍生物在催化液化过程中向单环芳烃衍生物和烷烯烃转化,分子量降低,提高了油品质量。     

液体弹珠：制备策略、物理性质及应用探索

Liquid marbles (LMs) are liquid droplets coated with a layer of lyophobic particles at the air-liquid interface. Since the pioneering work by Aussillous et al. in 2001, LMs have attracted significant attention owing to their facile fabrication, flexibility in the choice of the constituent particles and liquids, intriguing properties such as non-wetting and non-adhesive nature, satisfactory elasticity and stability, as well as promising applications in microfluidics, sensors, controlled release, and microreactors. The classical strategy for the preparation of LMs involves rolling a small volume of a droplet on a lyophobic powder bed for complete encapsulation of the liquid by the particles. In addition, various innovative methods, including electrostatic and coalescent approaches, have been developed for preparing special LMs with a complicated structure or morphology. Diverse materials such as water, surfactant solutions, liquid metals, reagents, blood, and even viscous adhesives have been employed as the internal liquid for the fabrication of LMs. Theoretically, any particulates such as lycopodium, polytetrafluoroethylene, Fe₃O₄, SiO₂, and graphite grains can be employed as the outer coating, but they are usually required to be lyophobic with sizes of less than hundreds of microns. The unique structure of the particle-covered droplet and the dual solid-liquid characteristics endow LMs with some unique and interesting properties, especially the non-wetting and non-adhesive nature. As the lyophobic coating particles restrain the internal liquid from contacting the substrate, LMs can move easily across either solid or liquid surfaces, neither wetting the substrate nor contaminating the internal liquid. An equally fascinating property of LMs is their satisfactory stability, which is necessary for most of their applications. The high stability of LMs stems from the protection of the coating powders and is embodied in both good mechanical stability (remaining intact after being released from a certain height or under a certain compression) and long lifetime (greatly suppressing the evaporation of the internal liquid). These extraordinary properties make LMs promising candidates for use in multitudinous fields, especially droplet microfluidics and microreactors. The potential application of LMs in microfluidics is ascribed to their non-wetting, non-adhesive nature and other features such as an ability to float on a liquid surface, coalescence, split, a small force of rolling friction, and response to external forces. Notably, LMs hold great promise for applications in microreactions, because they can create a confined reaction microenvironment, minimize reagent usage, facilitate unhindered gas exchange between the internal liquid medium and the surrounding environment, and allow the entry/exit of the reactants/products. We herein review the recent advances in LMs, such as manufacturing techniques, formation mechanisms, physical properties, and emerging applications. In particular, much attention is paid to the factors affecting the stability of LMs and the potential strategies to increase their stability. Moreover, this review discusses the challenges in the future development of LMs, suggests several possible ways of addressing these challenges, and forecasts the future development directions. We believe that this review can help researchers gain a better understanding of LMs and promote their further advances.     

磁性离子印迹技术用于元素形态分离分析

元素的形态决定了其在环境和生物过程中的不同行为,形态分析正在被分析化学、环境化学、地球化学、生态学、农学和生物医学等众多学科所关注。环境和生物样品基质复杂、化学形态多样、含量低且易转化是元素形态分析面临的挑战,因此对元素形态的甄别、定量、生态毒性评价和生理功能研究需要对原生形态进行高选择性识别和高效率分离。固相萃取是一种有效应对以上难题的方法,但现有材料和方法远不能满足要求。离子印迹聚合物可与印迹金属离子特异性结合,具有准确、灵敏、可靠的特点,近年来在元素形态分离富集和分析检测方面得到了较为广泛的应用。鉴于非磁性吸附剂在固相萃取操作时,需要将分散在样品溶液中的吸附材料经过离心或过滤分离,操作比较繁琐费时,而磁性材料易被外部磁场快速分离,因此操作简便快速的磁固相萃取正成为元素形态分离富集中一种极具潜力的方法。这篇综述系统总结了离子印迹技术的最新进展,包括离子印迹技术的原理、离子印迹聚合物的制备方法,并根据元素形态分析中离子印迹磁固相萃取的发展现状,分析了离子印迹技术所面临的挑战,最后对元素形态分析中离子印迹技术的未来发展方向和策略提出了建议,提出开发基于有机-无机杂化聚合的多功能磁性离子印迹纳米复合物用于样品的前处理是建立识别选择性高、分离能力强、吸附容量大、形态稳定性好的形态分析方法的一种重要举措。     

载体对包埋酶微环境的影响分析

包埋法固定化酶过程中,酶固定化载体的选择和设计是酶固定化过程的关键因素,适宜的载体微环境对酶活性和稳定性的影响尤为重要。论文首先分析并提出了影响固定化酶所处载体微环境的主要因素,包括载体的亲疏水性、结构形态和反应活性。载体的亲疏水性决定固定化酶微环境中的水分含量。载体的结构形态对酶形成的笼效应,以及载体的反应活性,包括共价键合、静电和氢键等的结合能力,影响酶构象的稳定性和运动性。另外,底物／产物的扩散速率和酶的可及性也同样受到载体的孔结构、孔分布以及载体反应活性的影响。本文介绍了常用的酶包埋载体,包括sol-gel二氧化硅、高分子水凝胶以及高分子－二氧化硅杂化凝胶固定化酶过程,结合上述影响酶微环境的因素,分析比较了三类载体固定化酶的包埋率、活性和稳定性,综述了为改善固定化酶微环境所进行改进研究的进展。     

Synthesis of polymer–inorganic patchy microcapsules with tunable patches

We introduce a facile and versatile approach for the formation of ball-like polymer–inorganic patchy microcapsules with a tunable shell by combining sol–gel chemistry of silica precursor and phase separation between the polymer and the precursor. Firstly, chloroform-in-water emulsion droplets containing poly(methyl methacrylate) (PMMA), silica precursor [tetraethyl orthosilicate (TEOS)] and co-surfactant sodium dioctyl sulfosuccinate (Aerosol OT or AOT) were prepared by shaking the mixture by hand. Due to the added AOT, water molecules diffuse into the chloroform droplets, and the tiny water droplets would coalesce gradually, triggering the formation of double emulsion droplets. Upon further solvent evaporation, the concentration of the polymer and the silica precursor in the oil shell of the double emulsions increases, leading to the phase separation between the polymer and the precursors (and partially formed silica through the hydrolysis and condensation of TEOS). Because of the confined geometry of the oil shell in the double emulsions, polymeric disc-like structures, stabilized by AOT, were dispersed in the silica precursors. Meanwhile, the silica precursor hydrolyzed and condensed when brought in contact with the aqueous solution, ultimately leading to the formation of a mineralized shell around the polymer domains and the hybrid patchy microcapsules. Effect of synthesis conditions, such as the amount of TEOS, AOT, and PMMA used, the pH value, and solvent evaporation rate on interfacial behavior of the solvent/water; and the morphology of the patchy microcapsules were investigated. Patchy microcapsules with tunable patch size and shape can be generated through tailoring the experimental parameters. Our study indicates that the hybrid patchy microcapsules can be formed by taking advantage of the sol–gel chemistry and the phase separation process, and the underlying generality of the synthesis procedure allows for a variety of applications, including drug storage, coatings, delivery, catalysis, and smart building blocks in self-assembling systems.     

转基因产品分析方法的研究进展

简要介绍了转基因产品的发展历程、优缺点以及对转基因产品进行检测分析的迫切性,着重综述了近期基于DNA、蛋白质、生物传感器以及联用技术检测转基因产品的分析方法,最后对转基因产品的分析方法进行了展望.     

三唑类药物研究新进展

三唑类化合物作为药物广泛应用于临床,是目前药物研究开发的重点领域之一．越来越多的高活性、低毒性、不良反应少、多药耐药性小、生物利用率高、药代动力学性质好、药物靶向性强、给药方式多样化、广谱、高疗效的三唑类化合物作为候选药物或药物用于临床医治多种疾病,显示出了三唑类化合物在医药领域的巨大开发价值和潜在的宽广应用．本文结合自己的工作,参考国内外近五年文献系统地综述了三唑类化合物作为药物在整个医药领域的研究与开发近况,包括抗真菌、抗细菌、抗结核、抗癌、抗病毒、抗炎镇痛、抗惊厥等,并展望其发展趋势与前景．希望该评论有助于为高活性低毒性三唑类医药合理设计提供新思路．     

石墨烯纤维：制备、性能与应用

石墨烯纤维是一种由石墨烯片层紧密有序排列而成的一维宏观组装材料。通过合理的结构设计和可控制备,石墨烯纤维能够将石墨烯在微观尺度的优异性能有效传递至宏观尺度,展现出优异的力学、电学、热学等性能,从而应用于功能织物、传感、能源等领域。目前,石墨烯纤维主要通过湿法纺丝、限域水热组装等方法制备得到,其性能可以通过对材料体系和制备工艺的优化而进一步提升。本文首先介绍了石墨烯纤维的制备方法,然后详细阐述了石墨烯纤维的性能,讨论了其性能提升策略,并总结了石墨烯纤维的应用,最后对石墨烯纤维的未来发展、挑战和前景进行了展望。     

Recent advance in synthesis and application of heteroatom zeolites

Incorporation of heteroatoms into the framewo rk of zeolites has become a significant strategy to improve their performance in catalysis and adsorption,because the obtained heteroatom zeolites exhibit quite different properties from the conventional aluminosilicate zeolites in aspects of surface acidity,pore structures,particle size and so on.In this review,the progress on the heteroatom zeolites including their synthesis and application is highlighted.First,the recent advance on the design and synthesis of different heteroatom zeolites is summarized.Special emphasis is placed on the introduction and comparison of three typical methods,including the direct synthesis,post synthesis and improved direct synthesis,for the traditional heteroatom zeolites(such as TS-1,Sn-MFI,Sn-β) and newly-reported heteroatom zeolites(such as W-MFI,Mo-MFI).According to their intrinsic characteristics,the application of heteroatom zeolites in diverse fields,such as production of fine chemicals,air pollution control and biomass conversion is then discussed.Finally,the challenges and perspective on the future development of heteroatom zeolites in low-cost preparation and practical application are proposed.     

电感耦合等离子体发射光谱法(ICP-AES)测定黄禾和谷子中15种元素

摘 要：提出了用等离子体发射光谱对通辽地区产黄禾和谷子中Na,Ca,Sn,Cu,Zn,Al,Mg,Fe,P,Si,K,Ba,Se,Mo,Mn 15种元素含量同时进行测定的方法,并对各元素作了加标回收实验,黄禾和谷子中各元素的平均回收率为96.67%～104.00%,RSD为0.78%～2.86%。方法简便、快速、准确地测定了黄禾和谷子中的元素。结果显示,在黄禾和谷子中K,P,Mg含量高,谷子中Ca,Mg,Fe,Zn和Mn的含量较黄禾中的高。黄禾和谷子中富含丰富的Na,Ca,Zn,Fe等元素,从微量元素角度看谷子中对身体有益的元素较黄禾高。     

前列舒通胶囊中26种无机元素的分析

目的：明确造成前列舒通胶囊不同批次间差异的标志性无机元素,并进行安全性评价。方法：采用ICP-MS测定制剂中Al、As、B、Ba、Ca、Cd、Co、Cr、Cu、Fe、K、Mg、Mn、Mo、Na、Ni、Pb、Sb、Se、Sn、Sr、Ti、Tl、V、Zn和Hg元素含量并进行数据分析。运用主成分及综合评分结合聚类分析手段,确定制剂的特征性元素;进行元素含量和相关性分析,明确不同批次各元素的差异及元素之间的关系;以多元素含量为指标,绘制无机元素谱图。结果：19批样品中均未检测出Se、Mo、Sn、Sb、Tl和Hg,且Pb、Cd、As、Cu、Hg均符合限量标准,无机元素含量谱图趋势一致。主成分分析提取了4个主成分,确定元素B、K、Al、V、Cr、Ca、Ti、Na、Co和Mn可作为特征元素。主成分得分图将19批样品分为两类,聚类分析及综合评分结果与其一致,两类样品中各元素含量存在差异性。相关性分析中,明确了B与K、Al、Cr正相关,K与Cr、Co正相关,V与Cr、Mn正相关,Mn与Co正相关,Ca、Ti、Na两两正相关。结论：通过分析前列舒通胶囊中无机元素含量,确定了特征元素,为前列舒通胶囊质量全面控制研究提供科学依据。     

Advancing cellulose-based nanotechnology

Nanotechnology has applications across most economic sectors and allows the development of new enabling science with broad commercial potential. Cellulose and lignocellulose have great potential as nanomaterials because they are abundant, renewable, have a nanofibrillar structure, can be made multifunctional, and self-assemble into well-defined architectures. To exploit their potential, R&D investments must be made in the science and engineering that will fully determine the properties and characteristics of cellulose and lignocellulose at the nanoscale, develop the technologies to manipulate self-assembly and multifunctionallity, and develop these new technologies to the point where industry can produce advanced and cost-competitive cellulose and lignocellulose-based products. Because many of the findings on nanostructues and nanoprocesses are not yet fully measurable, replicable, or understood, it will take substantial R&D investments. To most effectively and efficiently move forward, increased cooperation must occur among the cellulose/lignocellulose R&D community, the federal departments and agencies having interests and ongoing programs in nanotechnology, and industry. Cooperation is critical to capturing synergies, enhancing accomplishments, and avoiding unwarranted duplication of facilities and efforts.     

Intellectual property—The Foundation of Innovation: A scientist's guide to intellectual property

Increasingly, the activities of the practicing scientist inextricably intersect with the business world. Science is central to the development and delivery of many goods or services, and scientific discovery can directly, or indirectly, lead to substantial revenue generation. Scientists, however, have little training in the complex issues of intellectual property (IP), and often little understanding of their rights and obligations. Here, we define IP and disuss what it means to be an inventor or creator of IP. We define and differentiate between the primary forms of IP—trade secrets, copyright, trademarks, and patents—and discuss their implementation and implications for the practicing scientist.     

典型醇类物质超临界水氧化反应途径研究

采用自主设计的连续流动气封壁超临界水氧化反应装置,研究了典型醇类物质甲醇、乙醇和异丙醇在超临界水中氧化的反应途径,并归纳了醇类物质超临界水氧化反应的规律及特点。研究结果表明,甲醇超临界水氧化反应的主要中间产物为甲醛,同样条件下转化率较乙醇和异丙醇低;乙醇和异丙醇超临界水氧化反应的主要中间产物为丙酮、乙酸、乙醛和甲醇等。三种醇超临界水氧化过程中均涉及到大量活性自由基的相互作用,表现为脱氢、裂解和聚合等反应形式;产物包括碳链增长、不变、降低三种类型。总体来看,醇类物质超临界水氧化反应的趋势是向碳链降低的方向进行,即通过一系列中间产物最后生成CO₂和水。     

Monitoring of pesticide residues in Riyadh dates by SFE,MSE, SFC,and GC techniques

In the present work, simple and rapid extraction and analysis techniques of insecticide (OCPs, OPPs, pyrethroids), fungicide, acaricide, and herbicide residues in three cultivars’ of date fruits viz., Khalas, Sukkari, Nabout Seif and their seeds have been applied. The date cultivars were collected from eight local markets of Riyadh, KSA. The extraction of pesticide residues from the three varieties of date samples was conducted by rapid and new extraction techniques, Supercritical Fluid Extraction (SFE) and Microwave Solvent Extraction (MSE). The analysis was performed, without clean-up, by Supercritical Fluid Chromatography (SFC) and Gas Chromatography (GC) using different detectors. The results showed that the SFE, MSE, SFC and GC techniques are clearly faster, more sensitive and more cost effective than conventional methods. The recovery efficiency of SFE and MSE was 99% and 97%, respectively. The recoveries, MDL (Minimum Detection Limit) and repeatability achieved in this study meet the standards set for tolerance level monitoring of these pesticides. The mean levels of some tested residues of pyrethroids, herbicides, and fungicides in dates and their seeds are below the MRL (Maximum Residue Level). However, lindane (BHC gamma isomer), dieldrin, dimethoate, chlorpyrifos and all tested acaricide residues in date fruit samples exceeded the MRLs indicating a hazardous trend in the date palm cultivation. The data also showed a higher concentration of OP dimethoate in the date seeds, which is sometimes, used as animal feed. The present results provide important information on the current contamination status of the date fruits in Riyadh markets and point to the action needed for controlling the excessive application of pesticides. This study is the first monitoring and screening of pesticide residues of 6 groups in Saudi Arabian dates.     

电感耦合等离子体光谱法(ICP-AES)测定银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量

针对银精矿样品复杂,难消解的特点,研究了不同酸溶法和碱熔法对样品的消解情况,建立了硝酸,盐酸,氢氟酸,高氯酸消解银精矿的方法。根据元素灵敏度和抗干扰性,选定各元素的测定波长。通过酸溶样和碱熔样测定结果比对,验证了方法准确性。建立了四酸消解-电感耦合等离子体光谱法测定银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量的方法,元素的线性相关系数均在0.9999以上。通过共存元素干扰实验,确定了银精矿中高含量元素(铜、铅、锌、铁、锑、铋等)对测定元素结果没有影响。方法检出限：Cu 0.0063 mg/L, Pb 0.0159 mg/L ,Zn 0.0090 mg/L,As 0.0192 mg/L, Cd 0.0093 mg/L ,Ca 0.0084 mg/L, Mg 0.0075 mg/L, Mn 0.0081 mg/L。测定下限：Cu 0.0105mg/L,Pb 0.0265 mg/L, Zn 0.0150 mg/L, As 0.0320 mg/L, Cd 0.0155 mg/L, Ca 0.0140 mg/L, Mg 0.0125 mg/L,Mn 0.0135 mg/L。3个样品的相对标准偏差在0.87%~3.56%之间,加标回收率在95.00%~103.56%之间。方法流程短,操作简单,快速,灵敏度和再现性高,结果准确可靠,可以满足银精矿中铜、铅、锌、砷、镉、钙、镁、锰含量的测定。     

Effect of solvents on electro-spinnability of polystyrene solutions and morphological appearance of resulting electrospun polystyrene fibers

The effects of solvents and their properties on electro-spinnability of the as-prepared polystyrene (PS) solutions and the morphological appearance of the as-spun PS fibers were investigated qualitatively by means of a scanning electron microscope (SEM). The eighteen solvents used were benzene, t-butylacetate, carbontetrachloride, chlorobenzene, chloroform, cyclohexane, decahydronaphthalene (decalin), 1,2-dichloroethane, dimethylformamide (DMF), 1,4-dioxane, ethylacetate, ethylbenzene, hexane, methylethylketone (MEK), nitrobenzene, tetrahydrofuran (THF), 1,2,3,4-tetrahydronaphthalene (tetralin), and toluene. The PS solutions in 1,2-dichloroethane, DMF, ethylacetate, MEK, and THF could produce fibers with high enough productivity, while the PS solutions in benzene, cyclohexane, decalin, ethylbenzene, nitrobenzene, and tetralin were not spinnable. Qualitative observation of the results obtained suggested that the important factors determining the electro-spinnability of the as-prepared PS solutions are high enough values of both the dipole moment of the solvent and the conductivity of both the solvent and the resulting solutions, high enough boiling point of the solvent, not-so-high values of both the viscosity and the surface tension of the resulting solutions.     

揭开护手霜的神秘面纱——介绍一个化学实验类科普产品

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