首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   178篇
  免费   12篇
  国内免费   2篇
工业技术   192篇
  2023年   4篇
  2022年   14篇
  2021年   7篇
  2020年   11篇
  2019年   13篇
  2018年   16篇
  2017年   10篇
  2016年   11篇
  2015年   4篇
  2014年   5篇
  2013年   8篇
  2012年   7篇
  2011年   13篇
  2010年   12篇
  2009年   13篇
  2008年   9篇
  2007年   3篇
  2006年   1篇
  2005年   3篇
  2004年   1篇
  2003年   4篇
  2002年   3篇
  2001年   2篇
  2000年   3篇
  1998年   2篇
  1994年   2篇
  1993年   4篇
  1992年   1篇
  1991年   3篇
  1990年   2篇
  1989年   1篇
排序方式: 共有192条查询结果,搜索用时 15 毫秒
11.
Carbon nanotubes (CNTs) were deposited on various substrates namely untreated silicon and quartz, Fe-deposited silicon and quartz, HF-treated silicon, silicon nitride-deposited silicon, copper foil, and stainless steel mesh using thermal chemical vapor deposition technique. The optimum parameters for the growth and the microstructure of the synthesized CNTs on these substrates are described. The results show that the growth of CNTs is strongly influenced by the substrate used. Vertically aligned multi-walled CNTs were found on quartz, Fe-deposited silicon and quartz, untreated silicon, and on silicon nitride-deposited silicon substrates. On the other hand, spaghetti-type growth was observed on stainless steel mesh, and no CNT growth was observed on HF-treated silicon and copper. Silicon nitride-deposited silicon substrate proved to be a promising substrate for long vertically aligned CNTs of length 110–130 μm. We present a possible growth mechanism for vertically aligned and spaghetti-type growth of CNTs based on these results.  相似文献   
12.
Lanthanum modified Ba0.80Pb0.20Ti0.90Zr0.10O3 (BPZT) ceramics with composition Ba0.80−xLax Pb0.20Ti0.90Zr0.10O3; x = 0–0.01 in steps of 0.0025 were prepared by conventional solid state method. All the samples were sintered at 1325 °C after compacting in circular discs. Detailed structural and ferroelectric properties were carried out for sintered specimens. X-ray diffraction analysis for all the sintered specimens shows tetragonal structure with perovskite. Coercive field (Ec) and remanent polarization (Pr) to spontaneous polarization (Ps) ratio (Pr/Ps) was found to decrease with increase in temperature. Pr/Ps ratio was found to decrease with increase in x, except x = 0.0025.  相似文献   
13.
Most human deaths are caused by heart diseases. Such diseases cannot be efficiently detected for the lack of specialized knowledge and experience. Data science is important in healthcare sector for the role it plays in bulk data processing. Machine learning (ML) also plays a significant part in disease prediction and decision-making in medical care industry. This study reviews and evaluates the ML approaches applied in heart disease detection. The primary goal is to find mathematically effective ML algorithm to predict heart diseases more accurately. Various ML approaches including Logistic Regression, Support Vector Machine (SVM), k-Nearest Neighbor (k-NN), t-Distributed Stochastic Neighbor Embedding (t-SNE), Nave Bayes, and Random Forest were utilized to process heart disease dataset and extract the unknown patterns of heart disease detection. An analysis was conducted on their performance to examine the effecacy and efficiency. The results show that Random Forest out-performed other ML algorithms with an accuracy of 97%.  相似文献   
14.
This article provides a content analysis of publications on borosilicate glass and synroc, which are most widely used today for the immobilization of high-level radioactive wastes. Covering a period of 30 years, this study highlights the publication trends, the most productive countries, the language most frequently used, and the different categories of publications in these two subject areas. The research focuses on R&D efforts of different institutions and laboratories in these fields. For more information, contact S. Deokattey, Bhabha Atomic Research Centre, Library & Information Services Division, Trombay, Mumbai-400 085, India; e-mail clibscd6@magnum.barc.ernet.in.  相似文献   
15.
Fungal diseases result in significant losses of fruits and vegetables during handling, transportation and storage. At present, post-production fungal spoilage is predominantly controlled by using synthetic fungicides. Under the global climate change scenario and with the need for sustainable agriculture, biological control methods of fungal diseases, using antagonistic microorganisms, are emerging as ecofriendly alternatives to the use of fungicides. The potential of microbial antagonists, isolated from a diversity of natural habitats, for postharvest disease suppression has been investigated. Postharvest biocontrol systems involve tripartite interaction between microbial antagonists, the pathogen and the host, affected by environmental conditions. Several modes for fungistatic activities of microbial antagonists have been suggested, including competition for nutrients and space, mycoparasitism, secretion of antifungal antibiotics and volatile metabolites and induction of host resistance. Postharvest application of microbial antagonists is more successful for efficient disease control in comparison to pre-harvest application. Attempts have also been made to improve the overall efficacy of antagonists by combining them with different physical and chemical substances and methods. Globally, many microbe-based biocontrol products have been developed and registered for commercial use. The present review provides a brief overview on the use of microbial antagonists as postharvest biocontrol agents and summarises information on their isolation, mechanisms of action, application methods, efficacy enhancement, product formulation and commercialisation.  相似文献   
16.
This study aimed to assess the preferences and perceptions of texture‐modified three‐dimensional (3D) printed chocolate through three measures: two tasting tests and one survey. In the first test, 30 semitrained panelists ranked their overall preference from among the three samples of chocolate printed in a honeycomb pattern with infill percentages (IPs) of 25, 50, and 100%. The panelists ranked the samples based on appearance and hardness. In the second test, the same panelists nominated one preference between a 3D printed sample (100% IP) and a cast commercial chocolate sample. Friedman test indicated that there was no significant difference in overall preferences for hardness although the panelists significantly preferred the appearance of samples with 25 and 50% over the 100% infill. Furthermore, there was no significant difference in preference between the cast and 100% infill samples. The texture data of the chocolate samples showed that a higher force was required to break the chocolate samples as the IP increased from 25% (20.4 ± 1.1 N) to 100% (54.4 ± 1.5 N). Also, the 3D printed chocolate (printed in 100% IP) was found to be less hard than that of casted chocolate. In the survey of consumer perceptions, a total of 244 participated and assessed the samples for their intricate design and novel technology concept through a questionnaire. While there was a general awareness of 3D printing technology among these participants, many were impressed with the application of 3D printing to chocolate, as this was the first time they had seen this. The results obtained from the sensory tests and consumer survey provided a useful insight into consumers' perception of 3D food printing and the 3D products design. This awareness will be beneficial to promote this technology in the food industry.  相似文献   
17.
Three‐dimensional printing (3DP) of surimi requires a structural modifier to achieve a stable construct. This work investigated the effect of addition of sweet potato starch (0–10% wt/wt) on the physical properties (rheological properties, gel strength, water‐holding capacity [WHC], and microstructural characteristics) of surimi gels and the 3D printed behavior of these gels. The results showed that as the starch content increased, the viscosity of the starch–surimi mixture decreased facilitating the flow of the surimi out of the printer nozzle. The surimi gel with 8% sweet potato starch concentration showed good gel strength (2,021.70 g mm), WHC (82.39%), microstructural characteristics, and less cooking loss (1.95%). A comparison of the traditional surimi preparation method with 3DP showed that the surimi gel prepared by a 3D printed construct was softer in gel strength (1,398.65 g mm) and lower in hardness (945.17 g) although showing slightly higher cooking loss (6.76%) and lower WHC (72.66 g) than the conventional product. The results suggest that sweet potato starch can be effectively used as a structural enhancer for 3DP complex‐shaped surimi.  相似文献   
18.
Bhogal  Sangeeta  Sharma  Gaurav  Kumar  Amit  Sharma  Shweta  Naushad  Mu.  Alam  Manawwer  Stadler  Florian J. 《Topics in Catalysis》2020,63(11-14):1272-1285
Topics in Catalysis - In the present study, Ag2O–Al2O3–ZrO2 based trimetallic oxide nanocatalyst was designed using simple microwave assisted reduction method. It was characterized...  相似文献   
19.
20.
Wireless Personal Communications - With emerge of increasing research in domain of future wireless communications, massive multiple input multiple output (MIMO) attracted most of researchers...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号