全文获取类型
收费全文 | 4042篇 |
免费 | 436篇 |
国内免费 | 88篇 |
专业分类
电工技术 | 44篇 |
综合类 | 167篇 |
化学工业 | 2067篇 |
金属工艺 | 57篇 |
机械仪表 | 55篇 |
建筑科学 | 85篇 |
矿业工程 | 56篇 |
能源动力 | 23篇 |
轻工业 | 508篇 |
水利工程 | 4篇 |
石油天然气 | 136篇 |
武器工业 | 10篇 |
无线电 | 127篇 |
一般工业技术 | 333篇 |
冶金工业 | 99篇 |
原子能技术 | 43篇 |
自动化技术 | 752篇 |
出版年
2024年 | 12篇 |
2023年 | 72篇 |
2022年 | 107篇 |
2021年 | 138篇 |
2020年 | 115篇 |
2019年 | 141篇 |
2018年 | 121篇 |
2017年 | 112篇 |
2016年 | 137篇 |
2015年 | 157篇 |
2014年 | 191篇 |
2013年 | 291篇 |
2012年 | 265篇 |
2011年 | 255篇 |
2010年 | 185篇 |
2009年 | 242篇 |
2008年 | 213篇 |
2007年 | 209篇 |
2006年 | 234篇 |
2005年 | 212篇 |
2004年 | 182篇 |
2003年 | 143篇 |
2002年 | 151篇 |
2001年 | 122篇 |
2000年 | 97篇 |
1999年 | 87篇 |
1998年 | 74篇 |
1997年 | 50篇 |
1996年 | 49篇 |
1995年 | 47篇 |
1994年 | 33篇 |
1993年 | 24篇 |
1992年 | 21篇 |
1991年 | 14篇 |
1990年 | 7篇 |
1989年 | 12篇 |
1988年 | 12篇 |
1987年 | 9篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 6篇 |
1982年 | 1篇 |
1979年 | 2篇 |
1976年 | 1篇 |
1971年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1959年 | 2篇 |
1956年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有4566条查询结果,搜索用时 31 毫秒
171.
介绍生物制剂处理工艺、主要设备、技术参数及生产运行情况.1年多应用实践表明,该工艺在污酸废水处理中发挥重要作用.通过生物制剂处理工艺处理后的废水,满足硫酸车间循环水应用条件和烧结车间系统补水条件,从而使得烧结车间的水循环系统达到平衡. 相似文献
172.
《Food Control》2014
Zinc oxide (ZnO) nanoparticles have been proven to have strong antibacterial activity against food borne pathogens. The practical applications of different concentrations (0, 1, 3, 5 and 8 mM) of ZnO suspensions containing 0.3% citric acid were investigated against the pathogenic bacteria like, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Bacillus cereus. Zinc oxide suspensions (0, 1, 3, 5 and 8 mM) containing citric acid have shown a significant inhibitory effect on the growth of all strains during 12 h of incubation. Our results have also shown that 5 and 8 mM suspensions of ZnO were the most effective on all strains. These data suggested that the antibacterial activity of ZnO was concentration dependent. Thus 5 mM and 8 mM ZnO were selected for further studies, carried out in mango juice, as they showed a significant growth inhibition in TSB. ZnO NPs were more capable of reducing initial growth counts of all the above stated strains in mango juice. Results have also exhibited that ZnO and citric acid had inhibitory effect on the growth of all strains during 24 h culture period in mango juice, as compared to the control experiment, which was further confirmed in liquid culture. This is the first report, describing the antibacterial activity of ZnO NPs in mango juices that showed the potential of these nanoparticles for use as an antibacterial agent in the food industry. 相似文献
173.
Priyanka Mishra Pichiah Saravanan Gopinath Packirisamy Min Jang Chuanyi Wang 《International Journal of Hydrogen Energy》2021,46(44):22877-22906
The revolution in the arena of functional materials for the development of well advanced engineered photocatalyst can efficiently harness photon energy from a wide spectrum of electromagnetic radiation. These next-generation smart materials would be a spectacular approach in designing devices such as photovoltaic cells, photoelectrochemical cells, and photocatalytic fuel cells. Photocatalytic oxidation of water or wastewater for concurrent production of hydrogen and electric current has turned out as a principal concept for the construction of modern photocatalytic fuel cells (PFCs). Such PFCs mimics reverse photosynthesis process where electrical energy is generated from organic pollutants. In recent years many reviews on focusing the design, fabrication, and theoretical efficiency of the PFCs have been published. Hence the present review is aimed to unveil the wall-to-wall information starting from fundamentals spanning to working principles, structural configuration, electrochemical degradation of pollutants and photoelectrochemical properties, electron transport, thermodynamic behavior and columbic efficiency of studied PFCs. 相似文献
174.
175.
《Behaviour & Information Technology》2012,31(5):495-507
Though researchers agree on the role of psychological forces on individuals' decision-making and emphasise the need for developing decision-support systems (DSS) that make individuals aware of these forces, a framework that can guide us in building such systems is still non-existent. In this article, we attempt to bridge this gap by proposing an agent-based debiasing framework for developing investment DSS. Identifying the primary characteristics of major biases influencing investment decisions through a thorough literature review, we propose a taxonomy to categorise them as cognitive, affective or conative. Cognitive biases are information-processing biases. Affective biases involve general moods and emotions. Conative biases are relatively stable personality traits such as overconfidence and inertia. We then outline debiasing strategies for each of these bias categories and identify decision-support characteristics necessary in software agents to carry out the appropriate debiasing tasks. An agent-based DSS architecture is then proposed, and a detailed trading example triggering a sample bias detection and debiasing algorithm is discussed to demonstrate the feasibility of the proposed system. 相似文献
176.
Organic whey as a source of Lactobacillus strains with selected technological and antimicrobial properties 下载免费PDF全文
Anna Rzepkowska Dorota Zielińska Aleksandra Ołdak Danuta Kołożyn‐Krajewska 《International Journal of Food Science & Technology》2017,52(9):1983-1994
Twenty‐five strains, isolated from raw, non‐pasteurised, organic whey samples, were identified phenotypically and genotypically. Biochemical tests were performed, and enzyme profiles, antibiotic resistance and antimicrobial properties were investigated. Sixteen strains were identified as genus Lactobacillus. Based on 16S rDNA gene sequence, the strains were identified as Lb. plantarum and Lb. fermentum. All of the strains had β‐galactosidase activity, and some of them reduced nitrate content. All strains utilised carbohydrates. The tested strains were characterised by low or average lipolytic and esterolytic activity. Moreover, the strains showed low proteolytic activity which is advantageous for their use as starter cultures for foods with low protein content. Strains Lb. fermentum S20, SM1, SM3, S2R and Lb. plantarum SM5 produced harmful N‐acetyl‐β‐glucosaminidase; moreover, the strain S20 produced also β‐glucuronidase. None of the strains produced α‐chymotrypsin. In phenotypic studies, most of the test strains were susceptible to gentamicin, ampicillin, tetracycline, chloramphenicol, penicillin and erythromycin. Strains Lb. plantarum S1 and Lb. fermentum S4, S7, S8, S10, SM1 and SM3 did not possess any transfer resistance genes. Antagonistic activity of the culture LAB strains was assessed as high or moderate in relation to the indicator strains, with the greatest zones of inhibition for E.coli and the smallest for L. monocytogenes ATCC 15313. This study reveals that the LAB strains isolated from organic whey have high potential for food application. Some strains of species Lb. fermentum (S4, S7, S8, S10) have been identified as the best candidates. 相似文献
177.
《International Journal of Hydrogen Energy》2019,44(23):12024-12032
To stabilize bromine produced during a vanadium-bromine redox flow batteries (VBr RFBs) charging, a bromine complexing agent (BCA) should be effectively used as a supporting material in VBr electrolyte. However, there remains a problem of improving the unstable reversibility between V2+ and V3+ in electrolyte including halogen elements (Br and Cl). This paper describes two imidazole-based BCAs, which are 1,2-dimethyl-3-ethylimidazolium bromide (DMEIm: C7H13BrN2) and 1,2-dimethyl-3-propylimidazolium bromide (DMPIm: C8H15BrN2), for not only confirming the capture of bromine but also improving the redox reaction of vanadium ions in VBr electrolyte. The effectiveness of the proposed two imidazole-based BCAs is demonstrated through the following experiments: cyclic voltammetry (CV), nuclear magnetic resonance analysis (NMR), scanning electron microscopy (SEM) analysis and cyclic cell operation test. Experimental results show that both the diffusion coefficient and the peak currents of each electrolyte using the proposed imidazole-based BCAs increases linearly with the rise of scan rate on the recorded CV curves, providing improved reversible reaction of V2+/V3+ in negative electrolyte. It also exhibits that the electrolytes using the DMEIm and DMPIm provide significantly improved charge (discharge) capacities which are 9.38 (31.01) % and 11.8 (35.66) % higher than the pristine one, respectively, resulting in 13.27% and 14.36% higher current efficiencies. In addition, corrosion cracks on the separator surface due to bromine attack are not observed after the cyclic cell operation. Consequently, these results indicate that the proposed two imidazole-based BCAs can not only sequester bromine during the VBr RFB charging, but also enhance electrochemical reversibility caused by improving diffusion coefficient of vanadium. 相似文献
178.
179.
Antimicrobial effect of an Undaria pinnatifida composite film containing vanillin against Escherichia coli and its application in the packaging of smoked chicken breast 下载免费PDF全文
Hyun‐Ju Yang Ji‐Hyeon Lee Ka‐Yeon Lee Kyung Bin Song 《International Journal of Food Science & Technology》2017,52(2):398-403
To develop a value‐added product, we used the under‐utilised seaweed Undaria pinnatifida as a source material for the fabrication of a biodegradable film by extracting U. pinnatifida protein (UPP). UPP/gelatine composite films with different constituent ratios were prepared. In addition, the UPP/gelatine composite films containing vanillin (0.05%, 0.1% and 0.5%) were prepared as antimicrobial packaging material. To evaluate the utility of the UPP composite film containing 0.5% vanillin as food packaging material, smoked chicken breast samples inoculated with Escherichia coli were packed with the film and stored at 4 °C for 10 days. It was observed that packaging of smoked chicken breast with the UPP composite film containing vanillin decreased the population of the inoculated E. coli by 1.12 log CFU g?1 compared with that in the control sample. Thus, the UPP/gelatine composite film with added vanillin can be utilised as a packaging material for smoked chicken breast. 相似文献
180.
通过试验,探讨了化学激发作用对磨细矿渣活性的影响,采用CaO,NaOH,KAl(SO4)2·12H2O,Na2SO4四种化学试剂,主要研究了不同化学试剂对磨细矿渣不同的试验效果,为类似研究奠定了基础。 相似文献