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601.
Advances in molecular technologies over the past few decades, such as high-throughput DNA marker genotyping, have provided more powerful plant breeding approaches, including marker-assisted selection and genomic selection. At the same time, massive investments in plant genetics and genomics, led by whole genome sequencing, have led to greater knowledge of genes and genetic pathways across plant genomes. However, there remains a gap between approaches focused on forward genetics, which start with a phenotype to map a mutant locus or QTL with the goal of cloning the causal gene, and approaches using reverse genetics, which start with large-scale sequence data and work back to the gene function. The recent establishment of efficient CRISPR-Cas-based gene editing promises to bridge this gap and provide a rapid method to functionally validate genes and alleles identified through studies of natural variation. CRISPR-Cas techniques can be used to knock out single or multiple genes, precisely modify genes through base and prime editing, and replace alleles. Moreover, technologies such as protoplast isolation, in planta transformation, and the use of developmental regulatory genes promise to enable high-throughput gene editing to accelerate crop improvement.  相似文献   
602.
高校生物技术专业教学方法改革探索与实践   总被引:10,自引:1,他引:9  
韩新才 《广东化工》2008,35(1):118-120
根据现代教育理念和生物化工学科生物技术专业特点,在生物技术专业教学方法改革中,进行了利用教学课堂,坚持教书育人;更新教案内容,紧跟学科发展前沿;结合实际讲解基本概念,加深学生对核心知识理解;改革课堂教学模式,引导学生参与互动;加强理论与实践教学融合,培养学生创新能力等方面的改革与实践,为我国生物化工学科生物技术专业教学方法改革提供参考。  相似文献   
603.
为了提高我国抗生素产品在国际市场的核心竞争力,综述了国内外抗生素生产技术的相关研究成果,分析了各种生物技术的优劣.结果表明,发酵过程控制的优化成为抗生素发酵生产中迫切需要解决的课题;利用酶工程技术生产抗生素虽具有高效能、低消耗、无公害、长寿命、安全、自动化等优点,但将新的生物工程技术全部应用到酶工程上来使之能源源不断地生产出适合人类需要的酶来还需时日;原生质体融合技术和基因工程技术在实验条件下产生了新的抗生素,但在生产中还需解决工程菌的质量和抗生素的基因表达等问题;代谢工程的实质就是基因工程,只是涉及的基因改变的量远比基因工程巨大;以生物整体为研究对象的系统生物学技术、组学技术和重塑生命体的合成生物学技术将为抗生素的生产带来革故鼎新的变化,但也面临很多诸如系统复杂性难以处理、很多元件不相容和线路系统难以预料等技术挑战和合成生命等伦理挑战.  相似文献   
604.
放射性核素导致的土壤污染受到人们的日益关注,铀矿山生产引起的矿区生态环境污染治理与修复已成为环保行业研究热点。铀矿区核素污染土壤修复技术包括物理修复技术、化学修复技术和生物修复等。土壤挖掘、覆盖和清洗是应对突发事件的首选方法,可发挥拓展污染场地的实际利用功能。对复杂的污染场地应当根据实际情况,发挥多学科交叉的作用,制定具有成本效益和环境友好的不同的修复技术方案,成为铀矿区放射性污染土壤修复技术的主流选择。系统总结了物理修复技术、化学修复技术和生物修复技术的基础理论、作用机制和发展现状,探讨对不同场地修复需求制定特定的修复方案路径,展望铀矿区核素污染土壤修复标准制定方向,为铀矿区放射性核素铀污染土壤修复提供理论支撑和指导依据。  相似文献   
605.
史越  贾李佳  刘翟 《集成技术》2024,13(3):128-142
自人类进入信息时代以来,全球信息总量飞速膨胀,为数据存储行业带来极大挑战。当前的信息存储工具存在许多缺陷,如信息密度低、使用寿命短、环境污染等,而脱氧核糖核酸(DNA)作为天然的遗传信息载体,具有信息密度高、稳定性高、保存时间长、维护成本低等优点,可能成为信息存储领域的卓越选择。尽管 DNA 存储目前面临读写成本高、速度慢、错误率高等挑战,但在某些领域也有着独特的优势,如“冷”数据存储和军事加密存储等。目前,DNA 存储的潜在发展方向主要包括在军事、航空航天等特殊场景下的应用,高容错的编解码方案,生物活体存储体系,脱离测序的信息读取方法,以及集成化的存储系统和统一行业标准等。希望在不久的将来,DNA 存储能够实现规模化应用,迎来数据存储的新纪元。  相似文献   
606.
蒙特卡罗方法研究光动力疗法选择性光损伤   总被引:1,自引:1,他引:0       下载免费PDF全文
王爽  阮军  贺庆丽 《激光技术》2008,32(2):184-186
为了研究光动力疗法选择性光损伤,采用蒙特卡罗方法,建立了组织中光动力剂量数学模型。得到光动力剂量随组织厚度增加呈指数衰减的结果。光动力损伤是阈值过程,对肿瘤组织造成深层光动力损伤时,更多正常组织受到损伤。光斑半径对对肿瘤组织损伤深度有明显影响。结果表明,适量光敏剂能引起浅薄全面的肿瘤组织光动力损伤,深层光动力损伤伴随正常组织损伤。  相似文献   
607.
Oxygen, as a terminal electron acceptor, is an essential substrate in the aerobic bio-oxidation process, affecting bacterial vitality and bio-oxidation performance. In this study, a newfangled platform biotechnology of sealed-oxygen supply bioreactor (SOS-BR) was developed by improving gas pressure to significantly intensify oxygen transfer rate to resolve the formidable barriers of aerobic catalysis. In virtue of SOS-BR, the bio-productivity was greatly improved for three representative substrates (xylose, furfural, and glycerol) bio-oxidation with the whole-cell catalysis of Gluconobacter oxydans. The determination of oxygen transfer coefficient (KLα) established an upgraded theoretical dynamic model for gas pressure intensification biosystem. Additionally, viscosity measurement and combined pressure control strategy explained the inflection point phenomenon of productivity and confirmed the intensify mechanism. The smart strategy of significantly intensifying oxygen transfer provided insightful ideas for overcoming the stubborn obstacle of obligate aerobic catalysis, and further promoted the development and industrial practicability of bio-oxidation.  相似文献   
608.
Current environmental and safety considerations urge innovation to address the need for sustainable high-value chemicals that are embraced by consumers. This review discusses the concept of sustainable fragrances, as high-value, everyday and everywhere chemicals. Current and emerging technologies represent an opportunity to produce fragrances in an environmentally and socially responsible way. Biotechnology, including fermentation, biocatalysis, and genetic engineering, has the potential to reduce the environmental footprint of fragrance production while maintaining quality and consistency. Computational and in silico methods, including machine learning (ML), are also likely to augment the capabilities of sustainable fragrance production. Continued innovation and collaboration will be crucial to the future of sustainable fragrances, with a focus on developing novel sustainable ingredients, as well as ethical sourcing practices.  相似文献   
609.
To contribute to the use of bio-based materials in the building sector, a novel bio-based wall panel, with a high thermal performance level, is proposed in this work. The panel is based on an ancient rural technique, widely diffused in southern Italy, which makes use of Arundo donax L. canes combined with gypsum plaster to build walls and ceilings of rural buildings. The enhancement of the thermal capacity of these panels by means of the introduction in the canes of a natural wax oleogel (WO) is proposed in this paper. A specific experimental campaign aiming at the comparison of traditional and innovative panels was carried out to assess the enhanced thermal performance of the proposed solution. The maximum value of heat flow absorbed from the panel with WO was 61.08 W/m2 around a mean panel temperature of 24°C, corresponding to the melting temperature range of the WO. The panel without WO at the same temperature absorbed an incoming heat flow of 34.64 W/m2 which is about 57% of the panel with WO. The panel with WO released at a temperature of about 27.5°C, a heat flow of 43.42 W/m2. At the same temperature of about 27.5°C, the panel without WO released a heat flow of 34.38 W/m2 which is about 80% that of the panel with WO. The results highlighted that the addition of natural WO has enhanced the thermal capacity of the panel facilitating heat dissipation through the borders. These characteristics make the panel a suitable component for internal partitions of controlled temperature zones such as residential rooms, storage food areas, livestock buildings, and where it is necessary to obtain a constant environmental temperature. In particular, the null or low toxicity of the panel's materials allows for partition use, also in hygienically safe environments.  相似文献   
610.
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