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排序方式: 共有198条查询结果,搜索用时 31 毫秒
1.
John D. Rodney S. Deepapriya M. Cyril Robinson C. Justin Raj Suresh Perumal Byung Chul Kim S. Krishnan S. Jerome Das 《International Journal of Hydrogen Energy》2021,46(54):27585-27596
The production of hydrogen, a favourable alternative to an unsustainable fossil fuel remains as a significant hurdle with the pertaining challenge in the design of proficient, highly productive and sustainable electrocatalyst for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, the dysprosium (Dy) doped copper oxide (Cu1-xDyxO) nanoparticles were synthesized via solution combustion technique and utilized as a non-noble metal based bi-functional electrocatalyst for overall water splitting. Due to the improved surface to volume ratio and conductivity, the optimized Cu1-xDyxO (x = 0.01, 0.02) electrocatalysts exhibited impressive HER and OER performance respectively in 1 M KOH delivering a current density of 10 mAcm?2 at a potential of ?0.18 V vs RHE for HER and 1.53 V vs RHE for OER. Moreover, the Dy doped CuO electrocatalyst used as a bi-functional catalyst for overall water splitting achieved a potential of 1.56 V at a current density 10 mAcm?2 and relatively high current density of 66 mAcm?2 at a peak potential of 2 V. A long term stability of 24 h was achieved for a cell voltage of 2.2 V at a constant current density of 30 mAcm?2 with only 10% of the initial current loss. This showcases the accumulative opportunity of dysprosium as a dopant in CuO nanoparticles for fabricating a highly effective and low-cost bi-functional electrocatalyst for overall water splitting. 相似文献
2.
Encryption is one of the fundamental technologies that is used in the security of multimedia data. Unlike ordinary computer applications, multimedia applications generate large amount of data that has to be processed in real time. This work investigates the problem of efficient multimedia data encryption. A scheme known as the Randomized Huffman Table scheme was recently proposed to achieve encryption along with compression. Though this scheme has several advantages it cannot overcome the chosen plaintext attack. An enhancement of this Huffman scheme is proposed in this work which essentially overcomes the attack and improves the security. The proposed encryption approach consists of two modules. The first module is the Randomized Huffman Table module, the output of which is fed to the second XOR module to enhance the performance. Security analysis shows that the proposed scheme can withstand the chosen plaintext attack. The efficiency and security of the proposed scheme makes it an ideal choice for real time secure multimedia applications. 相似文献
3.
Pathogenic Bacteria Detection: A Hierarchical 3D Nanostructured Microfluidic Device for Sensitive Detection of Pathogenic Bacteria (Small 35/2018) 下载免费PDF全文
4.
Jonathan Keller Damian Carr Frances Love Paul Grabill Hieu Ngo Perumal Shanthakumaran 《Journal of Intelligent Manufacturing》2012,23(2):205-211
The US Army has launched an aggressive program to implement condition based maintenance on its rotary wing assets. Condition
Based Maintenance takes advantage of technology developments in the areas of machinery monitoring, signal processing and fault
modeling to reduce the cost of ownership through improved maintenance procedures. Documenting the reduction in maintenance
burden, cost savings and increased safety through early detection of helicopter faults is an important step in justifying
the program. This paper describes a novel technique used to detect a serious fault in the accessory section of the AH-64D
Apache main transmission. The technique determines if the primary or secondary clutch system is driving the aircraft accessories
through a tachometer speed ratio. The method has identified three aircraft operating on the secondary system allowing Army
maintenance crews to replace the affected transmissions and quickly restore the aircraft to operational status. 相似文献
5.
Sandeep Peddi Rapur Ram Varalakshmi Devi Boreddy Sridhar Avssn Krishna Kishore Chennu Siva Kumar Vishnubotla 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):192-194
We present an end‐stage renal disease patient on dialysis with fever. The primary source was right internal jugular vein catheter which had metastatic infections in the body probably via an arteriovenous communication in a cavity in left lung. Patient had right psoas muscle abscess and a left kidney abscess. An 18F‐fluorodeoxyglucose‐positron emission spectroscopy scan was done to find out left kidney abscess. A search of literature did not reveal many patients of psoas abscess secondary to infection of hemodialysis access. 相似文献
6.
Antifungal activity of five different essential oils in vapour phase for the control of Colletotrichum gloeosporioides and Lasiodiplodia theobromae in vitro and on mango 下载免费PDF全文
Anand Babu Perumal Periyar Selvam Sellamuthu Reshma B. Nambiar Emmanuel Rotimi Sadiku 《International Journal of Food Science & Technology》2016,51(2):411-418
Mango fruit has high commercial value; however, major postharvest losses are encountered throughout the supply chain due to postharvest diseases. These results lead to the search for natural fungicide for postharvest diseases control. The antifungal effects of five essential oils (thyme, clove, cinnamon, anise and vitex) were assessed by disc volatilisation method. Thyme oil vapours at 5 μL per Petriplate, and clove and cinnamon oil at 8 μL per Petriplate showed 100% growth inhibition of mango pathogens in vitro. GC/MS analysis of essential oil showed thymol (23.88), o‐cymol (23.88) and terpinolene (23.88) as the major constituents of thyme oil. Clove and cinnamon oils contain 3‐allyl‐2‐methoxyphenol (37.42%) and benzofuran 3‐methyl (17.97%), respectively. Thyme oil as a fumigant at 66.7 μL L?1 showed a significant (P < 0.05) inhibition on postharvest pathogens of mango fruits stored at 25 °C for 6 days. Results of our study suggest the possibility of using thyme oil as an alternate natural fungicide to manage postharvest diseases in mango. 相似文献
7.
Markus Fröbel Ajay Perumal Tobias Schwab Malte C. Gather Björn Lüssem Karl Leo 《Organic Electronics》2013,14(3):809-813
We report efficient and bright organic light-emitting devices operated by capacitive energy coupling. In this approach, the organic layers are enclosed between sputter-deposited hafnium dioxide layers to prevent charge carrier injection. When a sinusoidal voltage signal is applied to the electrodes, the devices emit bright green light whereas no detectable emission is generated upon application of a constant voltage. The efficiency of the process depends heavily on the frequency of the applied voltage signal. By optimizing the driving scheme, a record luminous efficacy for AC driven OLEDs of 2.7 lm/W at 500 cd/m2 is achieved. 相似文献
8.
Shanmuganathan Archunan Maharajan Athisuyambulingam Kumara Perumal Pradhoshini Narayanaswamy Yelappu Ganapiriya viswambaran Muthukumaravel Kannayiram Marckasagayam Priyadharshini Mohamed Saiyad Musthafa Caterina Faggio 《Microscopy research and technique》2022,85(4):1355-1362
Accumulation of pollutants in the aquatic system has a high impact on the reproductive physiology of crustaceans. The objective of the present study was to assess the possible histopathological effects of combined chlorpyrifos and cypermethrin (nurocombi) exposure on reproductive tissue in male freshwater crab Paratelphusa jacquemontii using light and electron microscopy. The testis of experimental crabs showed disorganization of testicular lobules, increased inters cellular space, necrosis, and cellular damage in both germinal cells and Sertoli cells. The treated vas deferens exhibited epithelial degeneration, misshaped spermatophores, decline in the number of spermatophores, and dehiscence of spermatophore wall. These clinical manifestations expressed in crabs following the exposure of nurocombi significantly reduce the testicular activity and substantially inhibits the seminal secretions, which ultimately lead to impairment of reproduction. 相似文献
9.
Muthupandi Nagaraj Devanathan Perumal Muthusamy Boominathan Nattamai Bhuvanesh 《Journal of Sulfur Chemistry》2014,35(1):24-30
The attempted selenium dioxide oxidation of substituted diphenacyl sulfides in anticipation of further functionalization led to a series of α -ketoacids 3 via oxidation followed by C?S bond cleavage. Two minor products, 5 and 6, have also been isolated and a mechanistic pathway for the formation of 3, 5 and 6 has been proposed. 相似文献
10.
Secure and reliable group communication is an active area of research. Its popularity is fuelled by the growing importance of group-oriented and collaborative applications. The central research challenge is secure and efficient group key management. The present paper is based on the huddle hierarchy based secure multicast group key management scheme using the most popular absolute encoder output type code named gray code. The focus is of twofolds. The first fold deals with the reduction of computation complexity which is achieved in this protocol by performing fewer multiplication operations during the key updating process. To optimize the number of multiplication operations, the fast Fourier transform, divide and conquer approach for multiplication of polynomial representation of integers, is used in this proposed work. The second fold aims at reducing the amount of information stored in the Group Center and group members while performing the update operation in the key content. Comparative analysis to illustrate the performance of various key distribution protocols is shown in this paper and it has been observed that this proposed algorithm reduces the computation and storage complexity significantly. 相似文献