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1.
马乐  张莹 《化学教育》2021,42(7):22-26
化学教材作为最重要的化学教学资源之一,其中丰富的英文资源潜藏着重要价值,合理应用教材中英文教学资源,在提升化学教师的专业能力、推动学生思维发展、培养学生人文精神等方面都具有积极意义。梳理新人教版高中化学必修1和必修2中的英文教学资源,将其归纳概括为3大类:与基本概念和原理相关的英文教学资源、化学物质名词英文教学资源和常见的化学元素英文教学资源。对3类英文教学资源的内容及特质进行列举分析,同时对其应用进行探讨,提出相关建议。  相似文献   

2.
Plant oil renewable resources as green alternatives in polymer science   总被引:3,自引:0,他引:3  
The utilization of plant oil renewable resources as raw materials for monomers and polymers is discussed and reviewed. In an age of increasing oil prices, global warming and other environmental problems (e.g. waste) the change from fossil feedstock to renewable resources can considerably contribute to a sustainable development in the future. Especially plant derived fats and oils bear a large potential for the substitution of currently used petrochemicals, since monomers, fine chemicals and polymers can be derived from these resources in a straightforward fashion. The synthesis of monomers as well as polymers from plant fats and oils has already found some industrial application and recent developments in this field offer promising new opportunities, as is shown within this contribution. (138 references.)  相似文献   

3.
汽爆技术促进中药资源高值化利用   总被引:2,自引:0,他引:2  
陈洪章  彭小伟 《化学进展》2012,(9):1857-1864
汽爆技术在中药资源高值化利用中发挥的作用正在逐渐体现:汽爆处理打破中药植物细胞壁的屏障结构,有利于有效成分的分离提取;汽爆过程物料自体水解发生去糖苷化作用使天然植物中的苷元与糖基分离,提高苷类物质提取和分离效率;汽爆应用于中药炮制和中药脱毒有高效、快速和避免有效成分流失等优点;汽爆处理有利于中药非药用组分如纤维素、半纤维素等的有效分离和利用,联产乙醇、丁醇等能源和化工产品。本文对汽爆技术在中药资源高值化利用中的研究进展进行了综述。  相似文献   

4.
木质生物质转化高附加值化学品   总被引:2,自引:0,他引:2  
林鹿  何北海  孙润仓  胡若飞 《化学进展》2007,19(7):1206-1216
本文阐述了木质生物质转化为主要化学品的类型及其转化途径,提出了从木质生物质转化高附加值化学品的新思路.木质生物质通过一定的降解或分解途径,可产生很多有重要价值的有机小分子化合物,这些有机小分子化合物有葡萄糖、木糖、苯丙烷单体及二聚体,气态小分子如CH4和CO,液态小分子如有机酸、醛、醇,重要基础平台化合物糠醛、乙酰丙酸、木糖醇、乙醇等.通过这些小分子有机化合物的转化,可产生替代石油基产品的高附加值化学品,对可持续发展具有重要意义.  相似文献   

5.
本文阐述了木质生物质转化为主要化学品的类型及其转化途径,提出了从木质生物质转化高附加值化学品的新思路。木质生物质通过一定的降解或分解途径,可产生很多有重要价值的有机小分子化合物,这些有机小分子化合物有葡萄糖、木糖、苯丙烷单体及二聚体,气态小分子如CH4和CO,液态小分子如有机酸、醛、醇,重要基础平台化合物糠醛、乙酰丙酸、木糖醇、乙醇等。通过这些小分子有机化合物的转化,可产生替代石油基产品的高附加值化学品,对可持续发展具有重要意义。  相似文献   

6.
木材热塑化   总被引:1,自引:0,他引:1  
利用适当的化学改性反应特别是经典的纤维索改性反应如酯化、醚化反应对木材进行化学改性,可使木材转化为可熔、可溶的新型热塑性高分子材料。这种热塑性木材可用普通塑料加工成型的方法进行加工,制造出许多新产品。为扩大木材的加工方法、劣废木材资源更有效的综合利用及提高木材的应用价值开辟了新的途径。放已成为近十年来木材综合利用新技术研究开发的新热点之一。本文综述这一研究领域的现状。  相似文献   

7.
The drastic climate change on global scale is becoming very serious. To curb the anthropogenic CO2 emissions will be one of the most important issues for the human society in the twenty-first century. The chemical industry can contribute to this issue from the viewpoint of green sustainable chemistry. We have been establishing various innovative catalyst technologies and can still continue further efforts. Considering the existence of huge infrastructure of the conventional processes based on fossil resources, it would be very difficult to turn into new technologies based on sustainable resources quickly and straightforwardly. Thus it may be good to apply more practical strategies along the realistic time line. Here we propose a strategy comprised of establishing more energy-effective chemical processes based on fossil resources in short term, utilizing biomasses as chemical feedstocks in large scale in middle term, and pursuit of the artificial photosynthesis as a final goal in long term. In this article, several topics in each category are introduced.  相似文献   

8.
胶原及明胶基天然高分子复合材料研究进展   总被引:4,自引:0,他引:4  
胶原及其降解物—明胶是自然界中存在的一类丰富的绿色资源,来源广泛,具有可再生、可降解的"绿色"特性。将它们与其它物质复合形成新的复合材料,有着良好的性能和新的特性从而使其具有广阔的应用前景。日益严峻的环境问题,石油资源濒临匮乏,废旧材料的回收等问题使得人们更加寻求新的绿色的环境友好材料。本文根据天然资源各自的结构和性质,从复合方法和机理出发,综述了胶原及明胶与其它天然高分子(壳聚糖、淀粉、丝素蛋白、海藻酸钠)进行共混和复合以制备新的生物复合材料方面的研究进展。  相似文献   

9.
The enormous diversity of chemical compounds now available is problematic for waste disposal and recovery of essential resources such as rare earth metals. Non-renewable resources are being depleted and need to be managed more effectively. To validate the potential of strategic metals, which often are multi-functional and thus find (competitive) applications in different technologies, a criticality concept is applied. This is based on qualitative and quantitative criteria characterizing the different transformations along supply chains: ranging from the resource deposit to the product and from there into the so-called re-phases or disposal and end-of-life. The trajectories of the resources in real space and time have to be transparent in order to optimize the resource efficiency and its long-ranging compatibility but also to minimize dissipation. This approach allows developing transparent narratives (“Stoffgeschichten”, “Stories of Stuff”) for a responsible and benign use of resources. Only then can re-integration of functional materials be achieved.  相似文献   

10.
Applied Biochemistry and Biotechnology - A number of transportation fuels can be produced from renewable resources. The major fractions of lignocellulosic biomass, cellulose and hemicellulose, can...  相似文献   

11.
The term Web 2.0 is a convenient shorthand for a new era in the Internet in which users themselves are both generating and modifying existing web content. Several types of tools can be used. With social bookmarking, users assign a keyword to a web resource and the collection of the keyword 'tags' from multiple users form the classification of these resources. Blogs are a form of diary or news report published on the web in reverse chronological order and are a popular form of information sharing. A wiki is a website that can be edited using a web browser and can be used for collaborative creation of information on the site. This article is a tutorial that describes how these new ways of creating, modifying, and sharing information on the Web are being used for on-line mass spectrometry resources.  相似文献   

12.
With the expansion of the Internet and World Wide Web (or the Web), research environments have changed dramatically. As a result, the need to be able to efficiently and securely access information and resources from remote computer systems is becoming even more critical. This paper describes the development of an extendable integrated Web-accessible simulation environment for computational science and engineering called Computational Science and Engineering Online (CSE-Online; http://cse-online.net). CSE-Online is based on a unique client-server software architecture that can distribute the workload between the client and server computers in such a way as to minimize the communication between the client and server, thus making the environment less-sensitive to network instability. Furthermore, the new software architecture allows the user to access data and resources on one or more remote servers as well as on the computing grid while having the full capability of the Web-services collaborative environment. It can be accessed anytime and anywhere from a Web browser connected to the network by either a wired or wireless connection. It has different modes of operations to support different working environments and styles. CSE-Online is evolving into middleware that can provide a framework for accessing and managing remote data and resources including the computing grid for any domain, not necessarily just within computational science and engineering.  相似文献   

13.
由新型冠状病毒引起的传染性肺炎的疫情导致国内大中小学普遍推迟了2020年春季学期的开学时间。为了落实教育部提出的"停课不停教、停课不停学"的要求,我们提出基于教学立方配合视频直播平台的在线教学方案,并用于有机化学课程的在线教学实践。利用教学立方,学生进行课前预习和课后复习;利用视频直播间作为虚拟教室进行课上教学,并使用教学立方进行互动。该方案不仅可以保证疫情防控期间教学进度和教学质量,基本做到在线学习与线下课堂教学质量实质等效。而且,疫情过后,仍然可以作为在线教学或者线上线下混合教学方案继续使用,为打造"金课"奠定基础。  相似文献   

14.
One of the tasks of management in analytical laboratories is the scheduling of analyses and the organization of the laboratory resources with respect to the workload. By a simulation of the laboratory operations, one can describe and eventually forecast the magnitude of the sample backlog and result delays with respect to the followed strategy to schedule samples and resources. However the design and validation of a simulation model is a lengthy and expensive task, requiring the help of a specialist in the area of operations research. In this paper an expert system is described that guides the laboratory manager through the various stages of the model design. The output of the expert system is a simulation model written in program code (SIMULA) that after compilation can be used to simulate the laboratory.  相似文献   

15.
超临界流体萃取技术制备高纯度聚丙烯酸   总被引:3,自引:0,他引:3  
本文使用超临界CO2 萃取技术抽提单体等小分子物质 ,从而提高聚丙烯酸纯度。通过改变温度、压力和二氧化碳流量 ,我们可以将单体抽提率提高到 96 9%左右  相似文献   

16.
For hundreds of millions of years, nature uses carbon dioxide in photosynthesis as a vital building block of life. The compound is also an essential part of the carbon cycle and is co‐responsible for the transport of carbon between Earth's spheres. However, over the last years CO2 has been closely associated with global warming since the immense emissions from mainly the burning of fossil resources has led to a vast increase in atmospheric CO2‐levels. Therefore, not only a reduction of emissions on a global scale is crucial but also a trend towards renewable resources is clearly visible and necessary due to depleting fossil resources. In this context, the use of CO2 as an abundant resource in the chemical industry can contribute its share.  相似文献   

17.
Intelligent use of the data available in the store of the analytical laboratory computer can provide much of the information necessary for the optimization of laboratory resources. The research manager can use such information to monitor the activity of various projects and the cost effectiveness of the analytical service.  相似文献   

18.
Rare earth element (REE) resources in coal-related materials are vast. Assuming a coal production rate of 600 million short tons per year with an average REE content of 200 ppm, the potential REE resource is 120,000 tons per year, which is similar to the annual global production of REEs. Most of those resources that are associated with coal-related materials are found in association with the gangue or ash-based content from the coal ore. Under normal coal plant operation, the REEs often end up in refuse piles or tailings impoundments. In many cases, these REEs can be recovered at low cost using appropriate coal preparation, heap leaching, solvent extraction and/or selective precipitation, followed by subsequent separation and purification of individual REEs. In the present research, the processing approach uses a natural pyrite stream, which was removed during coal cleaning and used to enhance leaching. Bio-oxidation has been used commercially to accelerate leaching, and this approach has been applied to coal-based materials. The ferric ions generated from bio-oxidation oxidize sulfide minerals such as pyrite, which generates acid. Both acid and ferric ions are helpful for leaching REEs, as well as for removing residual sulfides, thereby preventing future acid mine drainage and related liabilities. It can be seen that, recovery of REEs from coal waste materials can enable coal producers to use untapped REEs resources to produce revenue and extend resource life while simultaneously reducing future environmental issues and costs.  相似文献   

19.
Despite the growing popularity of X-ray absorption spectroscopy (XAS) in scientific research, many researchers do not receive formalized training on this technique. Some of them learned from online resources, which only briefly introduce XAS and its applications. Here, this article aims to provide the overview of tips about the XAS analysis, general rules, as well as required information for presenting XAS data in publications, and some common mistakes in XAS data interpretations. Armed with these basics, the motivated aspiring XAS researchers will find existing resources more accessible and can progress much faster in understanding and using XAS.  相似文献   

20.
陈涛  彭林才 《化学通报》2018,81(1):45-51
5-乙氧基甲基糠醛(EMF)被认为是可替代化石能源的非常有前途的新型液态生物燃料,近年来由生物质资源制备EMF引起了国内外越来越广泛的关注。目前开发的合成EMF途径主要以糖类化合物(如果糖、葡萄糖、蔗糖、菊糖等)为原料,在乙醇溶剂中通过酸催化反应获得。本文针对EMF合成的化学反应过程及最新研究进展进行了综述,着重从反应起始原料、催化合成技术、催化行为与特点、过程经济可行性等方面对其进行评述和对比,并分析了目前工业规模转化生物质资源合成EMF仍面临的科学难点,对今后该领域的研究前景进行了展望,指出未来研究应朝着反应高效化、环境友好化及资源可持续利用方向深入开展。  相似文献   

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