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1.
魏冰 《化学教育》2004,25(7):20-22
本文依据20世纪70年代以来国家统一颁布的化学教学大纲为线索,从课程发展的角度对我国中学化学课程中能力培养的问题进行了探讨。文章重点考察了以下3个问题:教学大纲中关于能力的提法、能力要素的确定、能力培养和科学探究的联系与区别。  相似文献   

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Cannabis is well-known for its numerous therapeutic activities, as demonstrated in pre-clinical and clinical studies primarily due to its bioactive compounds. The Cannabis industry is rapidly growing; therefore, product development and extraction methods have become crucial aspects of Cannabis research. The evaluation of the current extraction methods implemented in the Cannabis industry and scientific literature to produce consistent, reliable, and potent medicinal Cannabis extracts is prudent. Furthermore, these processes must be subjected to higher levels of scientific stringency, as Cannabis has been increasingly used for various ailments, and the Cannabis industry is receiving acceptance in different countries. We comprehensively analysed the current literature and drew a critical summary of the extraction methods implemented thus far to recover bioactive compounds from medicinal Cannabis. Moreover, this review outlines the major bioactive compounds in Cannabis, discusses critical factors affecting extraction yields, and proposes future considerations for the effective extraction of bioactive compounds from Cannabis. Overall, research on medicinal marijuana is limited, with most reports on the industrial hemp variety of Cannabis or pure isolates. We also propose the development of sustainable Cannabis extraction methods through the implementation of mathematical prediction models in future studies.  相似文献   

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众所周知,大多数磺胺用于治疗各种疾病,结构奇特的方酸具有特定的功能。我们成功地将磺胺结构单元引入方酸四碳环,制得14个新的含方酰基的磺胺衍生物,确证了结构。预期这类化合物有新的生物活性。  相似文献   

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This special issue provides a snapshot of the recent efforts on bio-inspired materials, including their unique properties, correlation between multiscale structures and properties, design and synthesis, and applications. We expect this issue can arouse more interest of readers in bio-inspired material chemistry, and then boost the progress of the related studies.  相似文献   

6.
张校刚 《电化学》2017,23(5):495
超级电容器因具有高功率密度、长循环寿命和使用温度范围宽等显著优势,已成为化学电源产业内新的亮点。作为一种大功率储能器件,超级电容器在轨道交通、现代通讯、航空航天、国防等战略新兴领域具有广泛的应用前景,全球需求量迅速增长。目前,限制超级电容器规模应用的关键问题是其能量密度偏低以及成本过高。如何在保证其高功率密度和长循环寿命优势的前提下,提高超级电容器能量密度并降低其成本是当今研究的热点。近年来,全球的超级电容器研究者针对这一关键问题,从电极材料设计、新型电解液开发及器件构筑等方面开展了一系列的工作,从理论研究到工程应用都取得了重要的突破。本刊邀请了超级电容器领域内具有丰富研究经验的8个团队撰写了8篇关于超级电容器的综述或者研究论文,介绍了当前超级电容器领域的研究现状、发展趋势和所面临的挑战,希望籍此能使广大读者更加深入了解超级电容器这一领域,并共同推动我国超级电容器相关研究的进一步发展。在此,对本专辑的所有作者、审稿人及编辑部工作人员的卓有成效的工作和付出表示衷心的感谢!  相似文献   

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This essay is the introductory paper for a special issue of Structural Chemistry explicitly dedicated to the premier Spanish calorimetrist and thermochemist, our colleague and friend, María Victoria Roux. The studies in this issue were written on the occasion of her recent retirement from the CSIC Institute of Physical Chemistry “Rocasolano,” Madrid.  相似文献   

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人们对稀土药用的兴趣普遍增加。最近Chemical Society Reviews在2006年第6期刊登了镧系元素药用研究专刊,专门介绍稀土药用研究的现状。针对该专刊和稀土药用研究的现状,作者讨论了稀土化合物药用研究的发展动向,特别讨论了需要解决的关键基础问题。从新药研究模式的转变得到启发,提出如何把负面生物效应转化为药理作用,如何从干预细胞信号网络入手进行研究,如何处理活性与毒副作用的关系,以及药物合理设计的策略等。  相似文献   

9.
Bio-inspired chemistry based on photoresponsive molecules is a rapidly developing new strategy to mimic the function of various biological systems. The interaction of electromagnetic radiation with molecular systems is ideally suited for the control and powering of dynamic processes at the speed of light. Besides typical applications in artificial photosynthesis, many other aspects, such as the catalytic turnover of substrates or the controlled release or uptake of small bioactive molecules, are readily verified with light-driven model systems. The potential of this novel approach in biomimetic chemistry is briefly explored in this concept article.  相似文献   

10.
The pharmacological activities in bioactive plant extracts play an increasing role in sustainable resources for valorization and biomedical applications. Bioactive phytochemicals, including natural compounds, secondary metabolites and their derivatives, have attracted significant attention for use in both medicinal products and cosmetic products. Our review highlights the pharmacological mode-of-action and current biomedical applications of key bioactive compounds applied as anti-inflammatory, bactericidal with antibiotics effects, and pain relief purposes in controlled clinical studies or preclinical studies. In this systematic review, the availability of bioactive compounds from several salt-tolerant plant species, mainly focusing on the three promising species Aster tripolium, Crithmum maritimum and Salicornia europaea, are summarized and discussed. All three of them have been widely used in natural folk medicines and are now in the focus for future nutraceutical and pharmacological applications.  相似文献   

11.
This paper gives an overview of weak aggregation due to long-range molecular forces beyond the first neighbor. Such subtle self-assemblies are an important part of modern colloidal chemistry and concern organic molecules as well as inorganic electrolytes and hybrid aggregates. Diverse aspects of such colloidal aggregations, as described in this special issue, can be characterized by the effective free energy per molecule involved. We discuss here expectations about emerging knowledge in this field and predictive modeling of inorganic as well as organic colloids and hybrid aggregates. Some still open questions are also given.  相似文献   

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PREFACE     
Ming-Qiu Zhang  Shi-Yong Liu 《高分子科学》2021,39(10):前插4-前插5
正We are delighted to present this special-themed issue of the Chinese Journal of Polymer Science(CJPS) devoted to the recent advances in self-healing polymeric materials. Selfhealing has been recognized as one of the most attractive topics for advanced polymers in the past few years, enabling their reworkability, durability and reliability.  相似文献   

14.
Weber T 《Chemistry & biology》2010,17(11):1168-1169
The production of bioactive compounds in heterologous hosts has become a valuable tool for the investigation of biosynthetic pathways and their rational engineering. In this issue of Chemistry & Biology, Zhang et?al. (2010) report the manipulation of E. coli for the production of erythromycin A.  相似文献   

15.
Natural bone is a unique nanostructured material made of collagen fibre matrix and hydroxyapatite (HA) nanocrystals, providing mechanical support and protection from the vertebrate skeleton. However, in severe cases like bone‐deficiencies, bone needs to be “externally” repaired. Initially, different biological solutions were developed in bone‐guided regeneration. However, due to the limitations with the existing biological grafts, a lot of researches have been devoted toward biomaterials including metals, ceramics, and polymers. On the basis of the interface reactions between the implant and the surrounding tissues, these biomaterials may be classified as “nearly inert” or bioactive. Interestingly, the bioactive materials exhibit a specific biological response, leading to the formation of a natural bonding junction between the bone and the implant during bone regeneration. Recently, a special attention has been paid to a new generation of bioactive materials, i.e. (nano)structured biomaterials composed of a bioresorbable polymer matrix reinforced with bioactive inorganic compounds. While (bio)ceramic component provides the bioactivity, these materials can be readily engineered in such a way that their resorption rate in the body match the formation rate of the new tissue. This review hence reports the different biological and non‐biological solutions developed in bone‐guided regeneration, with a special emphasis on polymer‐based materials, and our recent results obtained in osseointegration The bone physiology, and its natural regeneration are also described. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

16.
Since the golden age of antibiotics in the 1950s and 1960s actinomycetes have been the most prolific source for bioactive natural products. However, the number of discoveries of new bioactive compounds decreases since decades. New procedures (e.g., activating strategies or innovative fermentation techniques) were developed to enhance the productivity of actinomycetes. Nevertheless, compound identification remains challenging among others due to high rediscovery rates. Rapid and cheap genome sequencing as well as the advent of bioinformatical analysis tools for biosynthetic gene cluster identification in combination with mass spectrometry-based molecular networking facilitated the tedious process of dereplication. In recent years several studies have been dedicated to accessing the biosynthetic potential of Actinomyces species, especially streptomycetes, by using integrated genomic and metabolomic screening in order to boost the discovery rate of new antibiotics. This review aims to present the various possible applications of this approach as well as the newly discovered molecules, covering studies between 2014 and 2021. Finally, the effectiveness of this approach with regard to find new bioactive agents from actinomycetes will be evaluated.  相似文献   

17.
Issue no. 15 is a regular issue consisting of 20 research papers distributed over 7 different parts dealing with various fundamental studies, analytical methodologies, various aspects of proteins and protein biomarkers, affinity studies, genetics, pathogens and toxins, and enantioseparations.  相似文献   

18.
The Camellia sinensis plant provides a wide diversity of black, green, oolong, yellow, brick dark, and white tea. Tea is one of the majorly used beverages across the globe, succeeds only in the water for fitness and pleasure. Generally, green tea has been preferred more as compared to other teas due to its main constituent e.g. polyphenols which contribute to various health benefits. The aim of this updated and comprehensive review is to bring together the latest data on the phytochemistry and pharmacological properties of Camellia sinensis and to highlight the therapeutic prospects of the bioactive compounds in this plant so that the full medicinal potential of Camellia sinensis can be realised. A review of published studies on this topic was performed by searching PubMed/MedLine, Scopus, Google scholar, and Web of Science databases from 1999 to 2022. The results of the analysed studies showed that the main polyphenols of tea are the four prime flavonoids catechins: epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC), and epicatechin (EC) along with the beneficial biological properties of tea for a broad heterogeneity of disorders, including anticancer, neuroprotective, antibacterial, antiviral, antifungal, antiobesity, antidiabetes and antiglaucoma activities. Poor absorption and low bioavailability of bioactive compounds from Camellia sinensis are limiting aspects of their therapeutic use. More human clinical studies and approaching the latest nanoformulation techniques in nanoparticles to transport the target phytochemical compounds to increase therapeutic efficacy are needed in the future.  相似文献   

19.
Natural products with a variety of pharmacological effects are important sources for commercial drugs, and it is very crucial to develop effective techniques to selectively extract and isolate bioactive natural components from the plants against the background of sustainable development. Ionic liquids (ILs) are a kind of designable material with unique physicochemical properties, including good thermal stability, negligible vapor pressure, good solvation ability, etc. ILs have already been used in pharmaceuticals for extraction, purification, drug delivery, etc. It has been reported that multi-interactions, like hydrogen bonding, hydrophobic interactions, play important roles in the extraction of bioactive components from the plants. In this review, recent progress in the understanding of scientific essence of hydrogen bonding, the special interaction, in ILs was summarized. The extraction of various natural products, one important area in pharmaceutical, by conventional and functional ILs as well as the specific roles of multi-interactions in this process were also reviewed. Moreover, problems existing in bioactive compound extraction by ILs and the future developing trends of this area are given, which might be helpful for scientists, especially beginners, in this field.  相似文献   

20.
The delta-conotoxin EVIA from the Conus ermineus venom, a recently characterized toxin, exhibits cis-trans isomerism of the Leu12-Pro13 bond associated with the triggering of its biological activity. In this paper we use the pseudoproline concept to target the presumed bioactive cis conformation. We report the design and the synthesis of loop 2 analogs from residue 8 to 18 containing either the cis-inducing Cys(PsiMe,MePro)13 unit or the natural proline residue. NMR studies in water and molecular modeling allowed us to identify the amide bond "locked" in a cis conformation for as in the suggested bioactive form of the natural toxin.  相似文献   

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