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排序方式: 共有3712条查询结果,搜索用时 15 毫秒
51.
Mohammad Sabzinejad Farash SK Hafizul Islam Mohammad S. Obaidat 《Concurrency and Computation》2015,27(17):4897-4913
Password‐based two‐party authenticated key exchange (2PAKE) protocol enables two or more entities, who only share a low‐entropy password between them, to authenticate each other and establish a high‐entropy secret session key. Recently, Zheng et al. proposed a password‐based 2PAKE protocol based on bilinear pairings and claimed that their protocol is secure against the known security attacks. However, in this paper, we indicate that the protocol of Zheng et al. is insecure against the off‐line password guessing attack, which is a serious threat to such protocols. Consequently, we show that an attacker who obtained the users' password by applying the off‐line password guessing attack can easily obtain the secret session key. In addition, the protocol of Zheng et al. does not provide the forward secrecy of the session key. As a remedy, we also improve the protocol of Zheng et al. and prove the security of our enhanced protocol in the random oracle model. The simulation result shows that the execution time of our 2PAKE protocol is less compared with other existing protocols. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Calcium binding by both native and hydroxypropyl starches was studied in aqueous media under different pH, temperature and reaction times at various calcium: starch ratios. Calcium binding was markedly influenced by pHs and temperatures of the reaction mixture. Reaction times did not show marked influence on calcium binding. Maximum calcium binding was observed in alkaline pH and at lower temperature. Most of the calcium bound within the first 20 minutes. Thus, alkaline pH and lower temperature is more favourable for calcium binding by both native and hydroxypropyl rice starches compared to acidic pH and higher temperatures. 相似文献
55.
Md. Sayem Alam Andleeb Z. Naqvi Kabir-ud-Din 《Journal of surfactants and detergents》2007,10(1):35-40
The effect of additives (surfactants and polymers) and pH on the clouding behavior of promethazine hydrochloride (PMT, a phenothiazine
drug) was investigated. Cloud point (CP) decreases with increase in pH due to deprotonation of drug molecules. The same trend
occurs in the presence of surfactants. However, at constant pH, and depending on their structure and nature, these additives
behave differently. Anionic surfactants show peaked behavior, whereas cationic (conventional as well as geminis) and non-ionic
surfactants increase the CP, although the mechanisms differ. Cationic surfactants hinder drug association (due to interaggregate
repulsion) resulting in an increase in CP, while non-ionic surfactants form mixed micelles with the drug, increasing micelle
hydration and CP. Polymers can cause both a decrease as well as an increase in CP, depending on their molecular weight. A
large CP increase (with the increase in surfactant concentration) for gemini surfactants suggests they are excellent candidates
for drug delivery.
相似文献
Kabir-ud-DinEmail: |
56.
The objective of this paper is to present the results of comparative study of integral parameters for TRX and BAPL benchmark lattices of thermal reactors. The nuclear data processing code NJOY'99 was deployed for the generation of the 69-group cross-section library from the basic evaluated nuclear data files JENDL-3.2 and JEF-2.2. TRX and BAPL benchmark lattices were modeled with optimized inputs, which were suggested in the final report of the WIMS Library Update Project Stage-I. The inputs were the results of a detailed parametric study of the WIMS input options and also optimized for accuracy. The integral parameters (such as keff, ρ28, δ25, δ28, C1) of five uranium-fuel thermal assemblies: TRX-1 and TRX-2 and BAPL-1, BAPL-2, and BAPL-3 were calculated with the help of WIMSD-5B code based on the generated 69-group cross-section library. The calculated results are compared with those of experiments and it is found that the obtained results between the two libraries are in good agreement with each other. Besides, the calculated integral parameters are also well consistent with the measured values, which reflect the validation of the generated 69-group cross-section library and this library thus obtained is necessary to meet up the nuclear data for neutronics calculation of TRIGA Mark-II research reactor at AERE, Savar, Dhaka, Bangladesh. 相似文献
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Priti Tagde Agnieszka Najda Kalpana Nagpal Giriraj T. Kulkarni Muddaser Shah Obaid Ullah Sebastian Balant Md. Habibur Rahman 《International journal of molecular sciences》2022,23(5)
Breast cancer is one of the most common types of cancer among women globally. It is caused by mutations in the estrogen/progesterone receptors and conventional treatment methods are commonly utilized. About 70–80 percent of individuals with the early-stage non-metastatic disease may be cured. Conventional treatment is far less than the optimal ratio, as demonstrated through the high mortality rate of women with this cancer. However, conventional treatment methods like surgery, radiotherapy, and chemotherapy are not as effective as expected and lead to concerns about low bioavailability, low cellular uptake, emerging resistance, and adverse toxicities. A nanomedicine-based approach is a promising alternative for breast cancer treatment. The present era is witnessing rapid advancements in nanomedicine as a platform for investigating novel therapeutic applications and modern intelligent healthcare management strategies. This paper focuses on nanomedicine-based therapeutic interventions that are becoming more widely accepted for improving treatment effectiveness and reducing undesired side effects in breast cancer patients. By evaluating the state-of-the-art tools and taking the challenges involved into consideration, various aspects of the proposed nano-enabled therapeutic approaches have been discussed in this review. 相似文献
59.
This paper examines the impacts of CO2 emission reduction target and carbon tax on future technologies selection and energy use in Bangladesh power sector during 2005–2035. The analyses are based on a long-term energy system model of Bangladesh using the MARKAL framework. The analysis shows that Bangladesh will not be able to meet the future energy demand without importing energy. However, alternative policies on CO2 emission constraints reduce the burden of imported fuel, improve energy security and reduce environmental impacts. The results show that the introduction of the CO2 emission reduction targets and carbon taxes directly affect the shift of technologies from high carbon content fossil-based to low carbon content fossil-based and clean renewable energy-based technologies compared to the base scenario. With the cumulative CO2 emission reduction target of 10–20% and carbon tax of 2500 Taka/ton, the cumulative net energy imports during 2005–2035 would be reduced in the range of 39–65% and 37%, respectively, compared to the base scenario emission level. The total primary energy requirement would be reduced in the range of 4.5–22.3% in the CO2 emission reduction targets and carbon tax 2500 Taka/ton scenarios and the primary energy supply system would be diversified compared to the base scenario. 相似文献
60.
Nadir Ouldhamadouche Amine Achour Raul Lucio-Porto Mohammad Islam Shahram Solaymani Ali Arman Azin Ahmadpourian Hamed Achour Laurent Le Brizoual Mohamed Abdou Djouadi Thierry Brousse 《材料科学技术学报》2018,34(6):976-982
Vanadium nitride(VN) was deposited by DC-sputtering on a vertically aligned carbon nanotube(CNTs)template for the purpose of nano-structuration. This led to the fabrication of hierarchically composite electrodes consisting of porous and nanostructured VN grown on vertically aligned CNTs in a nano-treelike configuration for micro-supercapacitor application. The electrodes show excellent performance with an areal capacitance as high as 37.5 m F cm~(-2) at a scan rate of 2 mV s~(-1) in a 0.5 MK_2SO_4 mild electrolyte solution. Furthermore, the capacitance decay was only 15% after 20,000 consecutive cycles. Moreover,the capacitance was found to increase with VN deposit thickness. The X-ray photoelectron spectroscopy analyses of the electrodes before and after cycling suggest that the oxide layers that form at the VN surface is the responsible for the redox energy storage in this material. Such electrodes can compete with other transition metal nitride based electrodes for micro-supercapacitors. 相似文献