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1.
以“创新、协调、绿色、开放、共享”为内核的新发展理念,是对马克思主义发展理念的继承和发扬,极具时代精神,富含问题意识,为高校思想政治教育发展、教育教学改革实践提供了强大的理论支撑。本文以“通信原理”为例,阐述了新发展理念在课程改革中的思路和方法,实现了思想政治教育与专业基础课程有机融合,为深化高校教学改革、创新人才培养模式提供了思路。 相似文献
2.
《International Journal of Hydrogen Energy》2022,47(93):39338-39363
In the last few decades, global warming, environmental pollution, and an energy shortage of fossil fuel may cause a severe economic crisis and health threats. Storage, conversion, and application of regenerable and dispersive energy would be a promising solution to release this crisis. The development of porous carbon materials from regenerated biomass are competent methods to store energy with high performance and limited environmental damages. In this regard, bio-carbon with abundant surface functional groups and an easily tunable three-dimensional porous structure may be a potential candidate as a sustainable and green carbon material. Up to now, although some literature has screened the biomass source, reaction temperature, and activator dosage during thermochemical synthesis, a comprehensive evaluation and a detailed discussion of the relationship between raw materials, preparation methods, and the structural and chemical properties of carbon materials are still lacking. Hence, in this review, we first assess the recent advancements in carbonization and activation process of biomass with different compositions and the activity performance in various energy storage applications including supercapacitors, lithium-ion batteries, and hydrogen storage, highlighting the mechanisms and open questions in current energy society. After that, the connections between preparation methods and porous carbon properties including specific surface area, pore volume, and surface chemistry are reviewed in detail. Importantly, we discuss the relationship between the pore structure of prepared porous carbon with surface functional groups, and the energy storage performance in various energy storage fields for different biomass sources and thermal conversion methods. Finally, the conclusion and prospective are concluded to give an outlook for the development of biomass carbon materials, and energy storage applications technologies. This review demonstrates significant potentials for energy applications of biomass materials, and it is expected to inspire new discoveries to promote practical applications of biomass materials in more energy storage and conversion fields. 相似文献
3.
J. Thomas BRENNA 《粮油食品科技》2022,30(3):7-15
人体大脑和身体的发育,需要从食物中摄取均衡的营养物质。人类大脑是区分人类和其他动物的特征。食物中的必需脂肪酸是机体组织结构和功能的必要组成部分。Omega-6(O6)亚油酸(LA6)是皮肤组织的组成成分,且是炎症、血栓形成、免疫和其他信号分子的前体;Omega-3(O3)α-亚麻酸(ALA3),特别是其长链代谢产物——二十二碳六烯酸(DHA3),是大脑、视网膜和部分神经组织中的关键组分。从富含LA6脂肪酸(缺乏O3脂肪酸)的植物籽中提取出的廉价而优质油脂,是20世纪的西方国家食品工业生产的主要脂肪来源。在代谢通路中,高浓度的LA6脂肪酸可拮抗O3脂肪酸代谢,造成O3脂肪酸不足,因此,在给怀孕动物的饲料中,只提供富含LA6但缺乏O3脂肪酸的油脂作为唯一的脂肪来源,会导致幼崽大脑发育不良。过去20~30年的研究表明,低含量LA6且含DHA3的油脂可改善大脑的功能。近年来的研究较多集中在营养因素对大脑发育的影响,最新研究数据表明,脂肪酸平衡对营养不良儿童的大脑发育尤为重要。世界卫生组织(WHO)越来越重视大脑的营养健康,通过其下属的食品法典委员会,建议用于治疗严重急性营养不良儿童的即食治疗食品中,使用含有均衡脂肪酸组成/构成的脂肪。同样,脂肪酸均衡对老年人可能也很重要。目前,业界已经有了调整油脂成分的方法,以确保脂肪酸均衡,从而维持人体整个生命周期的大脑健康。 相似文献
4.
Liudmila Zakharova Viktoria Sharova Marina Izvolskaia 《International journal of molecular sciences》2021,22(1)
Different aspects of the reciprocal regulatory influence on the development of gonadotropin-releasing hormone (GnRH)-producing- and immune systems in the perinatal ontogenesis and their functioning in adults in normal and pathological conditions are discussed. The influence of GnRH on the development of the immune system, on the one hand, and the influence of proinflammatory cytokines on the development of the hypothalamic-pituitary-gonadal system, on the other hand, and their functioning in adult offspring are analyzed. We have focused on the effects of GnRH on the formation and functional activity of the thymus, as the central organ of the immune system, in the perinatal period. The main mechanisms of reciprocal regulation of these systems are discussed. The reproductive health of an individual is programmed by the establishment and development of physiological systems during critical periods. Regulatory epigenetic mechanisms of development are not strictly genetically controlled. These processes are characterized by a high sensitivity to various regulatory factors, which provides possible corrections for disorders. 相似文献
5.
Along with the advent of 5G era, China's transportation industry for intelligent development enters into the fast lane. Based
on the integration of communication technology, Internet of things technology, big data technology, cloud computing technology, ar-
tificial intelligence technology and so on, the whole process and all-round intelligent control are carried out in traffic construction,
traffic management, road transportation, traffic service and so on, so as to ensure smooth and safe travel and to provide good servic-
es to road, railway, civil aviation, water transportation and other transportation networks. It is the important feature of intelligent
transportation in the 5G era. This paper analyses the trend of application and development of 5G network in intelligent transporta-
tion, which is the research basis of perfecting transportation service and the scientific basis of promoting the intelligent and modern
development of transportation in China. 相似文献
6.
7.
如今人与自然的矛盾愈发凸显,生态系统失衡、资源危机等挑战接踵而至,可持续发展观应运而生,成为时代命题,也是时代目标。包装设计自然应当顺应时代需求,站在生态伦理视角重新思考其发展路径。针对包装中“过度包装”、“用材浪费”等有悖可持续发展要求的现象,从生态伦理视角出发,探究生态环保包装设计策略。引入生态伦理学理论,总结包装设计潜藏的生态伦理挑战,说明绿色生态包装设计的必要性与可行性,结合案例分析并阐述其设计策略,归纳出绿色生态包装设计的基本原则与设计方法。从生态伦理视角审视包装设计,有助于设计者建立生态环保意识与责任意识,了解包装设计的时代需求;同时跳脱出传统思维模式,对包装设计进行优化与创新。 相似文献
8.
早产是新生儿和 5 岁以下儿童死亡的主要原因,同时作为一种常见的临床不良妊娠结局,不仅增加了母婴短期和长期并发症的风险,而且给个人、家庭和社会造成巨大负担,其发病原因及机制较为复杂,其中母体血液微量元素变化对胎儿发育有着非常重要的影响,微量元素的不平衡,可能导致不良妊娠结局。关于微量元素对早产婴幼儿的作用研究甚少,故本文结合近些年国内外关于微量元素应用的研究,综述了微量元素(铁、铜、锌、硒、锰5种)与早产婴幼儿生长发育的关系,以及微量元素影响早产发生的作用机制(炎症反应、氧化应激、内分泌调节机制),以期为微量元素在早产婴幼儿的生长发育研究中提供一定的理论指导依据。 相似文献
9.
Katarzyna Kosznik-Kwanicka ukasz Grabowski Micha Grabski Mateusz Kaszubski Marcin Grniak Agata Jurczak-Kurek Grzegorz Wgrzyn Alicja Wgrzyn 《International journal of molecular sciences》2020,21(22)
Two newly discovered bacteriophages, isolated from chicken feces and infecting Salmonella enterica strains, are described in this report. These phages have been named vB_Sen-TO17 and vB_Sen-E22, and we present their molecular and functional characterization. Both studied viruses are able to infect several S. enterica strains and develop lytically, but their specific host ranges differ significantly. Electron microscopic analyses of virions have been performed, and full genome sequences were determined and characterized, along with molecular phylogenetic studies. Genomes of vB_Sen-TO17 (ds DNA of 41,658 bp) and vB_Sen-E22 (dsDNA of 108,987 bp) are devoid of homologs of any known or putative gene coding for toxins or any other proteins potentially deleterious for eukaryotic cells. Both phages adsorbed efficiently (>95% adsorbed virions) within 10 min at 42 °C (resembling chicken body temperature) on cells of most tested host strains. Kinetics of lytic development of vB_Sen-TO17 and vB_Sen-E22, determined in one-step growth experiments, indicated that development is complete within 30–40 min at 42 °C, whereas burst sizes vary from 9 to 79 progeny phages per cell for vB_Sen-TO17 and from 18 to 64 for vB_Sen-E22, depending on the host strain. Virions of both phages were relatively stable (from several percent to almost 100% survivability) under various conditions, including acidic and alkaline pH values (from 3 to 12), temperatures from −80 °C to 60 °C, 70% ethanol, chloroform, and 10% DMSO. These characteristics of vB_Sen-TO17 and vB_Sen-E22 indicate that these phages might be considered in further studies on phage therapy, particularly in attempts to eliminate S. enterica from chicken intestine. 相似文献
10.
肉桂是我国特色经济林树种,我国肉桂种植面积和年产量均居世界首位。我国肉桂主要分布在两广地区,其中广西为14.9万hm2,广东为8.9万hm2,两地面积占全国肉桂分布总面积的95%以上。肉桂既是著名的香料又是传统的名贵中药,具有极高的经济价值,发展肉桂产业对于促进农民增收、维护健康中国有着重要的意义。本研究综述了肉桂资源量、分布情况及主要利用部位,介绍肉桂主要产品(如桂皮,桂枝,肉桂粉及肉桂油)及加工技术现状、产品质量控制及其分析检测方法,分析了产业未来的发展趋势,并提出了产业发展的对策和措施:加强肉桂标准化示范基地建设,提高优质资源供给能力;提高肉桂加工利用技术水平,延长产业链;培育肉桂龙头企业,提高产品市场竞争力。为我国肉桂特色资源加工利用产业的可持续发展提供一定的思路。 相似文献